EX-99.1

Exhibit 99.1

July 13, 2006

LAFARGE S.A.

Debt Securities

Underwriting Agreement Standard Provisions

From time to time, Lafarge S.A., a société anonyme organized under the laws of the Republic of France (the “Company”), may enter into one or more underwriting agreements in the form of Annex A hereto that incorporate by reference these Standard Provisions (collectively with these Standard Provisions, an “Underwriting Agreement”) that provide for the sale of the securities designated in such Underwriting Agreement (the “Securities”) to the several Underwriters named therein (the “Underwriters”), for whom the Underwriter(s) named therein shall act as representative (the “Representative”). The Underwriting Agreement, including these Standard Provisions, is sometimes referred to herein as the “Agreement.” The Securities will be issued pursuant to an indenture to be dated as of July 18, 2006 (the “Indenture”) between the Company and Law Debenture Trust Company of New York, as trustee (the “Trustee”).

1. Registration Statement. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Securities Act”), a registration statement on Form F-3 (File No. 333-135665), including a prospectus (the “Basic Prospectus”), relating to the debt securities to be issued from time to time by the Company. The Company has also filed, or proposes to file, with the Commission pursuant to Rule 424 under the Securities Act a prospectus supplement specifically relating to the Securities (the “Prospectus Supplement”). The registration statement, as amended at the time it becomes effective, including the information, if any, deemed pursuant to Rule 430A, 430B or 430C under the Securities Act to be part of the registration statement at the time of its effectiveness, is referred to herein as the “Registration Statement”; and as used herein, the term “Prospectus” means the Basic Prospectus as supplemented by the prospectus supplement specifically relating to the Securities in the form first used (or made available upon request of purchasers pursuant to Rule 173 under the Securities Act) in connection with confirmation of sales of the Securities and the term “Preliminary Prospectus” means the preliminary prospectus supplement specifically relating to the Securities together with the Basic Prospectus. Capitalized terms used but not defined herein shall have the meanings given to such terms in the Registration Statement and the Prospectus. References herein to the Registration Statement, the Basic

Prospectus, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents incorporated by reference therein. The terms “supplement,” “amendment” and “amend” as used herein with respect to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any documents filed by the Company under the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission thereunder (the “Exchange Act”) subsequent to the date of the Underwriting Agreement which are deemed to be incorporated by reference therein. For purposes of this Agreement, the term “Effective Time” means the effective date of the Registration Statement with respect to the offering of Securities, as determined for the Company pursuant to Section 11 of the Securities Act and Item 512 of Regulation S-K, as applicable.

At or prior to the time when sales of the Securities will be first made (the “Time of Sale”), the Company will prepare certain information, identified in Schedule 3 to the Underwriting Agreement for such offering of Securities, which together with (i) the Basic Prospectus, as amended and supplemented to the date of the Underwriting Agreement, and (ii) the Preliminary Prospectus used most recently prior to the execution of the Underwriting Agreement, constitute the “Time of Sale Information.”

2. Purchase of the Securities by the Underwriters.

(a) Subject to the terms and conditions and in reliance upon the representations and warranties herein set forth, the Company agrees to issue and sell the Securities to the several Underwriters named in the Underwriting Agreement, and each Underwriter, subject to the terms and conditions and in reliance upon the representations and warranties herein set forth, agrees, severally and not jointly, to purchase from the Company the respective principal amount of Securities set forth opposite such Underwriter’s name in the Underwriting Agreement at the purchase price set forth in the Underwriting Agreement.

(b) Payment for and delivery of the Securities will be made at the time and place set forth in the Underwriting Agreement. The time and date of such payment and delivery is referred to herein as the “Closing Date.”

(c) The Company acknowledges and agrees that the Underwriters named in the Underwriting Agreement are acting solely in the capacity of an arm’s length contractual counterparty to the Company with respect to any offering of Securities contemplated hereby (including in connection with determining the terms of the offering) and not as a financial advisor or a fiduciary to, or an agent of, the Company or any other person. Additionally, no such Underwriter is advising the Company or any other person as to any legal, tax, investment, accounting or regulatory matters in any jurisdiction. The Company shall consult with its own advisors concerning such matters and shall be responsible for making its own independent investigation and appraisal of the transactions contemplated hereby, and such Underwriters shall have no responsibility or liability to the Company with respect thereto. Any review by such Underwriters named in the Underwriting Agreement of the Company, the transactions

contemplated thereby or other matters relating to such transactions will be performed solely for the benefit of the Underwriters and shall not be on behalf of the Company.

3. Representations and Warranties of the Company. The Company represents and warrants to each Underwriter that:

(a) Registration Statement and Prospectus. The Registration Statement is an “automatic effective registration statement” as defined under Rule 405 of the Securities Act that has been filed with the Commission not earlier than three years prior to the date hereof; and no notice of objection of the Commission to the use of such registration statement or any post-effective amendment thereto pursuant to Rule 401(g)(2) under the Securities Act has been received by the Company. No order suspending the effectiveness of the Registration Statement has been issued by the Commission and no proceeding for that purpose or pursuant to Section 8A of the Securities Act against the Company or related to the offering has been initiated or threatened by the Commission; as of the Effective Time, the Registration Statement complied in all material respects with the Securities Act and the Trust Indenture Act of 1939, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Trust Indenture Act”), and did not or will not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary in order to make the statements therein not misleading; and as of the date of the Prospectus and any amendment or supplement thereto and as of the Closing Date, the Prospectus did not and will not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that the Company makes no representation and warranty with respect to (i) that part of the Registration Statement that constitutes the Statement of Eligibility and Qualification (Form T-1) of the Trustee under the Trust Indenture Act or (ii) any statements or omissions in the Registration Statement and the Prospectus and any amendment or supplement thereto made in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representative expressly for use therein.

(b) Time of Sale Information. The Time of Sale Information, at the Time of Sale and at the Closing Date did not and will not, contain any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that the Company makes no representation and warranty with respect to any statements or omissions made in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representative expressly for use in such Time of Sale Information.

(c) Issuer Free Writing Prospectus. Other than any Preliminary Prospectus and the Prospectus, the Company (including its agents and representatives, other than the Underwriters in their capacity as such) has not made, used, prepared, authorized, approved or referred to and will not prepare, make, use, authorize, approve or refer to

any “written communication” (as defined in Rule 405 under the Securities Act) that constitutes an offer to sell or solicitation of an offer to buy the Securities (each such communication by the Company or its agents and representatives (other than a communication referred to in clause (i) below) an “Issuer Free Writing Prospectus”) other than (i) any document not constituting a prospectus pursuant to Section 2(a)(10)(a) of the Securities Act or Rule 134 under the Securities Act or (ii) the documents listed on Schedule 3 to the Underwriting Agreement and other written communications approved in writing in advance by the Representative. Each such Issuer Free Writing Prospectus complied in all material respects with the Securities Act, has been filed in accordance with the Securities Act (to the extent required thereby) and, when taken together with any Preliminary Prospectus accompanying, or delivered prior to delivery of, or filed prior to the first use of such Issuer Free Writing Prospectus, did not, and at the Closing Date will not, contain any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that the Company makes no representation and warranty with respect to any statements or omissions made in each such Issuer Free Writing Prospectus in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representative expressly for use in any Issuer Free Writing Prospectus. Each Issuer Free Writing Prospectus does not include any information that conflicts with the information contained in the Registration Statement, including any document incorporated therein and any prospectus supplement deemed to be a part thereof that has not been superseded or modified.

(d) Incorporated Documents. The documents incorporated by reference in the Registration Statement, the Prospectus or the Time of Sale Information, when filed with the Commission, conformed or will conform, as the case may be, in all material respects with the requirements of the Exchange Act and did not and will not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(e) Financial Statements. The financial statements and the related notes thereto included or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus comply in all material respects with the applicable requirements of the Securities Act and the Exchange Act, as applicable, and present fairly the financial position of the Company and its subsidiaries as of the dates indicated and the results of their operations and the changes in their cash flows for the periods specified; such financial statements have been prepared in conformity with International Financial Reporting Standards applied on a consistent basis throughout the periods covered thereby, and the supporting schedules included or incorporated by reference in the Registration Statement present fairly the information required to be stated therein; and the other financial information included or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus has been derived from the accounting records of the Company and its subsidiaries and presents fairly the information shown thereby.

(f) No Material Adverse Change. Except as disclosed in or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus, since the date of the latest audited financial statements of the Company included or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus, there has been no material adverse change, nor any development or event involving a prospective material loss or adverse change, in the condition (financial or other), business, prospects, properties or results of operations of the Company and its subsidiaries taken as a whole, and, except as disclosed in, contemplated by or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus, there has been no dividend or distribution of any kind declared, set aside for payment, paid or made by the Company on any class of its capital stock, neither the Company nor any of its subsidiaries has incurred any liability or obligation, direct or contingent, outside of the ordinary course, that is material to the Company and its subsidiaries taken as a whole, nor has there been any material loss or interference with the business of the Company and its subsidiaries from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor disturbance or dispute or any action, order or decree of any court or arbitrator or governmental or regulatory authority, except in each case as otherwise disclosed in the Registration Statement, the Time of Sale Information and the Prospectus.

(g) Organization and Good Standing. The Company and each of its Principal Subsidiaries (as defined below) have been duly organized and are validly existing and in good standing (where applicable) under the laws of their respective jurisdictions of organization, are duly qualified to do business and are in good standing (where applicable) in each jurisdiction in which their respective ownership or lease of property or the conduct of their respective businesses requires such qualification, and have all power and authority necessary to own or hold their respective properties and to conduct the businesses in which they are engaged, except where the failure to be so qualified or have such power or authority would not, individually or in the aggregate, have a material adverse effect on the business, properties, management, financial position, results of operations or prospects of the Company and its subsidiaries taken as a whole or on the performance by the Company of its obligations under the Securities (a “Material Adverse Effect”).

(h) Capitalization. The Company has an authorized capitalization as set forth in the Registration Statement, the Time of Sale Information and the Prospectus under the heading “Capitalization and Indebtedness of Lafarge”; and all the outstanding shares of capital stock or other equity interests of each Principal Subsidiary of the Company have been duly and validly authorized and issued, are fully paid and non-assessable and are owned directly or indirectly by the Company, free and clear of any lien, charge, encumbrance, security interest, restriction on voting or transfer or any other claim of any third party (except in each case as otherwise described in the Registration Statement, the Time of Sale Information and the Prospectus).

(i) Due Authorization. The Company has full right, power and authority to execute and deliver this Agreement, the Securities and the Indenture (collectively, the “Transaction Documents”) and to perform its obligations hereunder and thereunder; and all action required to be taken for the due and proper authorization, execution and delivery of each of the Transaction Documents and the consummation of the transactions contemplated thereby has been duly and validly taken.

(j) The Indenture. The Indenture has been duly authorized, executed and delivered by the Company and has been duly qualified under the Trust Indenture Act and constitutes a valid and legally binding agreement of the Company enforceable against the Company in accordance with its terms, subject to applicable bankruptcy, insolvency and similar laws affecting creditors’ rights generally and to general principles of equity (collectively, the “Enforceability Exceptions”).

(k) The Securities. The Securities have been duly authorized by the Company and, when duly executed, authenticated, issued and delivered as provided in the Indenture and paid for as provided herein, will be duly and validly issued and outstanding and will constitute valid and legally binding obligations of the Company enforceable against the Company in accordance with their terms, subject to the Enforceability Exceptions, and will be entitled to the benefits of the Indenture.

(l) Descriptions of the Transaction Documents. Each Transaction Document conforms in all material respects to the description thereof contained in the Registration Statement, the Time of Sale Information and the Prospectus.

(m) Underwriting Agreement. The Underwriting Agreement has been duly authorized, executed and delivered by the Company.

(n) No Violation or Default. The Company is not (i) in violation of its charter or by-laws or similar organizational documents; (ii) in default, and no event has occurred

that, with notice or lapse of time or both, would constitute such a default, in the due performance or observance of any term, covenant or condition contained in any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company is a party or by which the Company is bound or to which any of the property or assets of the Company is subject; or (iii) in violation of any law or statute or any judgment, order, rule or regulation of any court or arbitrator or governmental or regulatory authority, except, in the case of clauses (ii) and (iii) above, for any such default or violation that would not, individually or in the aggregate, have a Material Adverse Effect.

(o) No Conflicts. The execution, delivery and performance by the Company of each of the Transaction Documents, the issuance and sale of the Securities and compliance by the Company with the terms thereof and the consummation of the transactions contemplated by the Transaction Documents will not (i) conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, or result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of the Company pursuant to, any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company is a party or by which the Company is bound or to which any of the property or assets of the Company is subject, (ii) result in any violation of the provisions of the charter or by-laws or similar organizational documents of the Company or (iii) result in the violation of any law or statute or any judgment, order, rule or regulation of any court or arbitrator or governmental or regulatory authority, except, in the case of clauses (i) and (iii) above, for any such conflict, breach or violation that would not, individually or in the aggregate, have a Material Adverse Effect.

(p) No Consents Required. No consent, approval, authorization, order, registration or qualification of or with any court or arbitrator or governmental or regulatory authority is required for the execution, delivery and performance by the Company of each of the Transaction Documents, the issuance and sale of the Securities and compliance by the Company with the terms thereof and the consummation of the transactions contemplated by the Transaction Documents, except for such consents, approvals, authorizations, orders and registrations or qualifications (i) as have been obtained under the Securities Act and the Trust Indenture Act and (ii) as may be required under applicable state securities laws in connection with the purchase and distribution of the Securities by the Underwriters.

(q) Legal Proceedings. Except as described in the Registration Statement, the Time of Sale Information and the Prospectus, there are no legal, governmental or regulatory investigations, actions, suits or proceedings pending to which the Company or any of its subsidiaries is or may be a party or to which any property of the Company or any of its subsidiaries is or may be the subject that, individually or in the aggregate, if determined adversely to the Company or any of its subsidiaries, could reasonably be expected to have a Material Adverse Effect; no such investigations, actions, suits or proceedings are threatened or, to the best knowledge of the Company, contemplated by any governmental or regulatory authority or threatened by others; and (i) there are

no current or pending legal, governmental or regulatory actions, suits or proceedings that are required under the Securities Act to be described in the Registration Statement that are not so described in the Registration Statement and the Prospectus and (ii) there are no contracts or other documents that are required under the Securities Act to be filed as exhibits to the Registration Statement or described in the Registration Statement or the Prospectus that are not so filed as exhibits to the Registration Statement or described in the Registration Statement, the Time of Sale Information and the Prospectus.

(r) Independent Accountants. Deloitte & Associés, who have certified certain financial statements of the Company and its subsidiaries, and Ernst & Young LLP, who have certified certain financial statements of Lafarge North America Inc., are each an independent registered public accounting firm with respect to the Company and its subsidiaries within the applicable rules and regulations adopted by the Commission and the Public Accounting Oversight Board (United States) and as required by the Securities Act.

(s) Investment Company Act. The Company is not and, after giving effect to the offering and sale of the Securities and the application of the proceeds thereof as described in the Registration Statement, the Time of Sale Information and the Prospectus, will not be an “investment company” or an entity “controlled” by an “investment company” within the meaning of the Investment Company Act of 1940, as amended, and the rules and regulations of the Commission thereunder (collectively, “Investment Company Act”).

(t) Forward-Looking Statements. No forward-looking statement (within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act) contained or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus has been made or reaffirmed without a reasonable basis or has been disclosed other than in good faith.

(u) Status under the Securities Act. The Company is not an ineligible issuer and is a well-known seasoned issuer, in each case as defined under the Securities Act, in each case at the times specified in the Securities Act in connection with the offering of the Securities.

4. Further Agreements of the Company. The Company covenants and agrees with each Underwriter that:

(a) Filings with the Commission. The Company will (i) pay the registration fees for this offering within the time period required by Rule 456(b)(1) under the Securities Act prior to the Closing Date and (ii) file the Prospectus in a form approved by the Underwriters with the Commission pursuant to Rule 424 under the Securities Act not later than the close of business on the second business day following the date of determination of the public offering price of the Securities or, if applicable, such earlier time as may be required by Rule 424(b) and Rule 430A, 430B or 430C under the

Securities Act. The Company will file any Issuer Free Writing Prospectus to the extent required by Rule 433 under the Securities Act; and the Company will furnish copies of the Prospectus and each Issuer Free Writing Prospectus (to the extent not previously delivered) to the Underwriters in New York City prior to 10:00 A.M., New York City time, on the second business day next succeeding the date of this Agreement in such quantities as the Representative may reasonably request.

(b) Delivery of Copies. The Company will deliver, without charge, to each Underwriter during the Prospectus Delivery Period (as defined below), as many copies of the Prospectus (including all amendments and supplements thereto) and each Issuer Free Writing Prospectus (if applicable) as the Representative may reasonably request. As used herein, the term “Prospectus Delivery Period” means such period of time after the first date of the public offering of the Securities as in the opinion of counsel for the Underwriters a prospectus relating to the Securities is required by law to be delivered (or required to be delivered but for Rule 172 under the Securities Act) in connection with sales of the Securities by any Underwriter or dealer.

(c) Issuer Free Writing Prospectus. The Company (including its agents and representatives, other than the Underwriters in their capacity as such) agrees that, unless it has obtained or will obtain, as the case may be, the prior written consent of the Representative, it has not made and will not make any offer relating to the Securities that would constitute an Issuer Free Writing Prospectus or that would otherwise constitute a “free writing prospectus” (as defined in Rule 405) required to be filed by the Company with the Commission or retained by the Company under Rule 433; provided that the prior written consent of the Representative shall be deemed to have been given in respect of the Issuer Free Writing Prospectuses, if any, included on Schedule 3 to the Underwriting Agreement.

(d) Amendments or Supplements; Issuer Free Writing Prospectuses. Before preparing, using, authorizing, approving, referring to or filing any Issuer Free Writing Prospectus, and before filing any amendment or supplement to the Registration Statement or the Prospectus, the Company will furnish to the Representative and counsel for the Underwriters a copy of the proposed Issuer Free Writing Prospectus, amendment or supplement for review and will not prepare, use, authorize, approve, refer to or file any such Issuer Free Writing Prospectus or file any such proposed amendment or supplement to which the Representative reasonably objects unless, in the case of a filing, the Company is required by law to make such filing.

(e) Notice to the Representative. The Company will advise the Representative promptly, and confirm such advice in writing, (i) when any amendment to the Registration Statement has been filed or becomes effective; (ii) when any supplement to the Prospectus or any amendment to the Prospectus or any Issuer Free Writing Prospectus has been filed; (iii) of any request by the Commission for any amendment to the Registration Statement or any amendment or supplement to the Prospectus or the receipt of any comments from the Commission relating to the Registration Statement or any other request by the Commission for any additional

information; (iv) of the issuance by the Commission of any order suspending the effectiveness of the Registration Statement or preventing or suspending the use of any Preliminary Prospectus or the Prospectus or the initiation or threatening of any proceeding for that purpose or pursuant to Section 8A of the Securities Act; (v) of the occurrence of any event within the Prospectus Delivery Period as a result of which the Prospectus, the Time of Sale Information or any Issuer Free Writing Prospectus as then amended or supplemented would include any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary in order to make the statements therein, in the light of the circumstances existing when the Prospectus, the Time of Sale Information or any such Issuer Free Writing Prospectus is delivered to a purchaser, not misleading; (vi) of the receipt by the Company of any notice of objection of the Commission to the use of the Registration Statement or any post-effective amendment thereto pursuant to Rule 401(g)(2) under the Securities Act; and (vii) of the receipt by the Company of any notice with respect to any suspension of the qualification of the Securities for offer and sale in any jurisdiction or the initiation or threatening of any proceeding for such purpose. The Company will use its reasonable best efforts to prevent the issuance of any such order suspending the effectiveness of the Registration Statement, preventing or suspending the use of any Preliminary Prospectus or the Prospectus or suspending any such qualification of the Securities and, if any such order is issued, to obtain as soon as possible the withdrawal thereof.

(f) Ongoing Compliance. (1) If during the Prospectus Delivery Period (i) any event shall occur or condition shall exist as a result of which the Prospectus as then amended or supplemented would include any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary in order to make the statements therein, in the light of the circumstances existing when the Prospectus is delivered to a purchaser, not misleading or (ii) it is necessary to amend or supplement the Prospectus to comply with law, the Company will immediately notify the Underwriters thereof and forthwith prepare and, subject to paragraph (c) above, file with the Commission and furnish to the Underwriters and to such dealers as the Representative may designate, such amendments or supplements to the Prospectus as may be necessary so that the statements in the Prospectus as so amended or supplemented will not, in the light of the circumstances existing when the Prospectus is delivered to a purchaser, be misleading or so that the Prospectus will comply with law and (2) if at any time prior to the Closing Date (i) any event shall occur or condition shall exist as a result of which the Time of Sale Information as then amended or supplemented would include any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances, not misleading or (ii) it is necessary to amend or supplement the Time of Sale Information to comply with law, the Company will immediately notify the Underwriters thereof and forthwith prepare and, subject to paragraph (d) above, file with the Commission (to the extent required) and furnish to the Underwriters and to such dealers as the Representative may designate, such amendments or supplements to the Time of Sale Information as may be necessary so that the statements in the Time of Sale Information as so amended or supplemented will not, in the light of the

circumstances, be misleading or so that the Time of Sale Information will comply with law.

(g) Blue Sky Compliance. The Company will arrange, if necessary, for the qualification of the Securities for offer and sale under the securities or Blue Sky laws of such jurisdictions as the Representative shall reasonably request and will continue such qualifications in effect so long as required for distribution of the Securities; provided that the Company shall not be required to (i) qualify as a foreign corporation or other entity or as a dealer in securities in any such jurisdiction where it would not otherwise be required to so qualify, (ii) file any general consent to service of process in any such jurisdiction or (iii) subject itself to taxation in any such jurisdiction if it is not otherwise so subject.

(h) Earning Statement. The Company will make generally available to its security holders and the Representative as soon as practicable an earning statement that satisfies the provisions of Section 11(a) of the Securities Act and Rule 158 of the Commission promulgated thereunder.

(i) Clear Market. During the period from the date hereof through and including the Closing Date or such later date as is specified in the Underwriting Agreement, the Company will not, without the prior written consent of the Representative, offer, sell, contract to sell or otherwise dispose of any debt securities issued or guaranteed by the Company and having a tenor of more than one year, other than debt securities offered and sold exclusively outside the United States in reliance on Regulation S under the Securities Act.

(j) Use of Proceeds. The Company will apply the net proceeds from the sale of the Securities as described in the Registration Statement, the Time of Sale Information and the Prospectus under the heading “Use of Proceeds.”

(k) No Stabilization. The Company will not take, directly or indirectly, any action designed to or that could reasonably be expected to cause or result in any stabilization or manipulation of the price of the Securities.

(l) Filing of Exchange Act Documents. The Company will file promptly all reports required to be filed by the Company with the Commission pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act during the Prospectus Delivery Period.

(m) Record Retention. The Company will, pursuant to reasonable procedures developed in good faith, retain copies of each Issuer Free Writing Prospectus that is not filed with the Commission in accordance with Rule 433 under the Securities Act.

(n) French selling restriction. The Company represents and agrees that it has not offered or sold and will not offer or sell, directly or indirectly, the Securities to the public in France (appel public à l’épargne), and has not distributed or caused to be distributed and will not distribute or cause to be distributed to the public in France, the Prospectus or any other offering material relating to the Securities, and that such offers, sales and distributions have been and will only be made in France through an international syndicate to qualified investors (investisseurs qualifiés), as defined in, and in accordance with, Articles L.411-1, L.411-2, D.411-1, D.411-2, D.734-1, D.744-1, D.754-1 and D.764-1 of the French Code monétaire et financier, except that qualified investors shall not include individuals. The direct or indirect distribution to the public in France of any Securities so acquired may be made only as provided by Articles L.411-1, L.411-2, L.412-1 and L.671-8 to L.671-8-3 of the Code monétaire et financier and applicable regulations thereunder.

5. Certain Agreements of the Underwriters. Each Underwriter hereby represents and agrees that

(a) It has not and will not use, authorize use of, refer to, or participate in the planning for use of, any “free writing prospectus”, as defined in Rule 405 under the Securities Act (which term includes use of any written information furnished to the Commission by the Company and not incorporated by reference into the Registration Statement and any press release issued by the Company) other than (i) a free writing prospectus that, solely as a result of use by such Underwriter, would not trigger an obligation to file such free writing prospectus with the Commission pursuant to Rule 433 (other than a free writing prospectus permitted under clause (b) below); (ii) any Issuer Free Writing Prospectus listed on Schedule 3 to the Underwriting Agreement or prepared pursuant to Section 4(d) above; or (iii) any free writing prospectus prepared by such underwriter and approved by the Company in advance in writing (each such free writing prospectus referred to in clauses (i) or (iii), an “Underwriter Free Writing Prospectus”).

(b) It has not and will not, without the prior written consent of the Company, use any free writing prospectus that contains the final terms of the Securities unless such terms have previously been included in a free writing prospectus filed with the Commission; provided that Underwriters may use a term sheet substantially in the form of Schedule 4 to the Underwriting Agreement without the consent of the Company or containing substantially the same information as contained in Schedule 4.

(c) It is not subject to any pending proceeding under Section 8A of the Securities Act with respect to the offering (and will promptly notify the Company if any such proceeding against it is initiated during the Prospectus Delivery Period).

(d) Each Underwriter severally represents, warrants and agrees that: in relation to each Member State of the European Economic Area which has implemented the Prospectus Directive (each, a “Relevant Member State”), it has not made and will not make an offer of the Securities to the public in that Relevant Member State, except that it may make an offer of Securities to the public in that Relevant Member State at any time under the following exemptions under the Prospectus Directive (as defined below), if they have been implemented in that Relevant Member State: (i) to legal entities which are authorized or regulated to operate in the financial markets or, if not so authorized or regulated, whose corporate purpose is solely to invest in securities; (ii) to any legal entity which has two or more of the following (1) an average of at least 250 employees during the last financial year; (2) a total balance sheet of more than €43,000,000 and (3) an annual net turnover of more than €50,000,000, as shown in its last annual or consolidated accounts; (iii) to fewer than 100 natural or legal persons (other than qualified investors as defined in the Prospectus Directive) subject to obtaining the prior consent of the Joint Book-Running Managers for any such offer; or (iv) in any other circumstances falling within Article 3(2) of the Prospectus Directive, provided that no such offer of Securities to the public shall result in a requirement for the publication by the Company or the Underwriters of a prospectus pursuant to Article 3 of the Prospectus Directive.

For the purposes of the preceding paragraphs, the expression “offer of Securities to the public” in relation to any Securities in any Relevant Member State means the communication in any form and by any means of sufficient information on the terms of the offer and the Securities to be offered so as to enable an investor to decide to purchase the Securities, as the same may be varied in that Member State by any measure implementing the Prospectus Directive in that Member State and the expression “Prospectus Directive” means Directive 2003/71/EC and includes any relevant implementing measure in each Relevant Member State.

(e) Each Underwriter severally represents and agrees that it has not offered or sold and will not offer or sell, directly or indirectly, the Securities to the public in France (appel public à l’épargne), and has not distributed or caused to be distributed and will not distribute or cause to be distributed to the public in France, the Prospectus or any other offering material relating to the Securities, and that such offers, sales and distributions have been and will only be made in France through an international syndicate to qualified investors (investisseurs qualifiés), as defined in, and in accordance with, Articles L.411-1, L.411-2, D.411-1, D.411-2, D.734-1, D.744-1, D.754-1 and D.764-1 of the French Code monétaire et financier, except that qualified investors shall not include individuals. The direct or indirect distribution to the public in France of any Securities so acquired may be made only as provided by Articles L.411-1, L.411-2, L.412-1 and L.621-8 to L.621-8-3 of the Code monétaire et financier and applicable regulations thereunder.

6. Conditions of Underwriters’ Obligations. The obligation of each Underwriter to purchase Securities on the Closing Date as provided herein is subject to the performance by the Company of its covenants and other obligations hereunder and to the following additional conditions:

(a) Registration Compliance; No Stop Order. No order suspending the effectiveness of the Registration Statement shall be in effect, and no proceeding for such purpose, pursuant to Rule 401(g)(2) or pursuant to Section 8A under the Securities Act shall be pending before or threatened by the Commission; the Prospectus and each Issuer Free Writing Prospectus shall have been timely filed with the Commission under the Securities Act (in the case of an Issuer Free Writing Prospectus, to the extent required by Rule 433 under the Securities Act) and in accordance with Section 4(a) hereof.

(b) Representations and Warranties. The representations and warranties of the Company contained herein shall be true and correct on the date hereof and on and as of the Closing Date; and the statements of the Company and its officers made in any certificates delivered pursuant to this Agreement shall be true and correct on and as of the Closing Date.

(c) No Downgrade. Subsequent to the execution and delivery of this Agreement, (i) no downgrading shall have occurred in the rating accorded the Securities or any other debt securities of the Company by any “nationally recognized statistical rating organization,” as such term is defined by the Commission for purposes of Rule 436(g)(2) under the Securities Act and (ii) no such organization shall have publicly announced that it has under surveillance or review, or has changed its outlook with respect to, its rating of the Securities or of any other debt securities of the Company (other than an announcement with positive implications of a possible upgrading).

(d) No Material Adverse Change. No event or condition of a type described in Section 3(f) hereof shall have occurred or shall exist, which event or condition is not described in the Time of Sale Information (excluding any amendment or supplement thereto) and the Prospectus (excluding any amendment or supplement thereto) and the

effect of which in the judgment of the Representative makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Securities on the terms and in the manner contemplated by this Agreement, the Time of Sale Information and the Prospectus.

(e) Officer’s Certificate. The Representative shall have received on and as of the Closing Date a certificate of an executive officer of the Company who has specific knowledge of the Company’s financial matters and is satisfactory to the Representative (i) confirming that such officer has carefully reviewed the Registration Statement, the Time of Sale Information and the Prospectus and, to the best knowledge of such officer, the representations set forth in Sections 3(a) and 3(b) hereof are true and correct, (ii) confirming that the other representations and warranties of the Company in this Agreement are true and correct and that the Company has complied with all agreements and satisfied all conditions on its part to be performed or satisfied hereunder at or prior to the Closing Date and (iii) to the effect set forth in paragraphs (a), (c) and (d) above.

(f) Comfort Letters. On the date of this Agreement and on the Closing Date, Deloitte & Associés and Ernst & Young Audit shall have furnished to the Representative, at the request of the Company, letters, dated the respective dates of delivery thereof and addressed to the Underwriters, in form and substance reasonably satisfactory to the Representative, containing statements and information of the type customarily included in accountants’ “comfort letters” to underwriters with respect to the financial statements and certain financial information contained or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus; provided that the letter delivered on the Closing Date shall use a “cut-off” date no more than three business days prior to the Closing Date.

(g) Opinion of Counsel for the Company. Cleary Gottlieb Steen & Hamilton LLP, counsel for the Company, shall have furnished to the Representative, at the request of the Company, their written opinion, dated the Closing Date and addressed to the Underwriters, in form and substance reasonably satisfactory to the Representative, to the effect set forth in Annex B hereto.

(h) Opinion of Internal Counsel for the Company. Michel Bisiaux, general counsel of the Company, shall have furnished to the Representative a written opinion, dated the Closing Date and addressed to the Underwriters, in form and substance reasonably satisfactory to the Representative, to the effect set forth in Annex C hereto.

(i) Opinion of Counsel for the Underwriters. The Representative shall have received on and as of the Closing Date an opinion of Davis Polk & Wardwell, counsel for the Underwriters, with respect to such matters as the Representative may reasonably request, and such counsel shall have received such documents and information as they may reasonably request to enable them to pass upon such matters.

(j) No Legal Impediment to Issuance. No action shall have been taken and no statute, rule, regulation or order shall have been enacted, adopted or issued by any federal, state or foreign governmental or regulatory authority that would, as of the Closing Date, prevent the issuance or sale of the Securities; and no injunction or order of any federal, state or foreign court shall have been issued that would, as of the Closing Date, prevent the issuance or sale of the Securities.

(k) Good Standing. The Representative shall have received on and as of the Closing Date an extract from the commercial registry of Paris with respect to the Company and satisfactory evidence of the good standing of Lafarge North America Inc. and Lafarge Canada Inc. in their respective jurisdictions of organization.

(l) Additional Documents. On or prior to the Closing Date, the Company shall have furnished to the Representative such further certificates and documents as the Representative may reasonably request.

All opinions, letters, certificates and evidence mentioned above or elsewhere in this Agreement shall be deemed to be in compliance with the provisions hereof only if they are in form and substance reasonably satisfactory to counsel for the Underwriters.

7. Indemnification and Contribution.

(a) Indemnification of the Underwriters. The Company agrees to indemnify and hold harmless each Underwriter, its affiliates, directors and officers and each person, if any, who controls such Underwriter within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act, from and against any and all losses, claims, damages and liabilities (including, without limitation, legal fees and other expenses incurred in connection with any suit, action or proceeding or any claim asserted as such fees and expenses are incurred), joint or several, that arise out of, or are based upon, (i) any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, or caused by any omission or alleged omission to state therein a material fact required to be stated therein or necessary in order to make the statements therein, not misleading, or (ii) any untrue statement or alleged untrue statement of a material fact contained in the Prospectus (or any amendment or supplement thereto), any Issuer Free Writing Prospectus or any Time of Sale Information, or caused by any omission or alleged omission to state therein a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading, in each case except insofar as such losses, claims, damages or liabilities arise out of, or are based upon, any untrue statement or omission or alleged untrue statement or omission made therein in reliance upon and in conformity with any information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representative expressly for use therein.

(b) Indemnification of the Company. Each Underwriter agrees, severally and not jointly, to indemnify and hold harmless the Company, its directors, its officers who signed the Registration Statement and each person, if any, who controls the Company within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act to the same extent as the indemnity set forth in paragraph (a) above, but only with respect to any losses, claims, damages or liabilities that arise out of, or are based upon, any untrue statement or omission or alleged untrue statement or omission made in reliance upon and in conformity with any information relating to such Underwriter furnished to the Company in writing by such Underwriter through the Representative expressly for use in the Registration Statement, the Prospectus (or any amendment or supplement thereto), any Issuer Free Writing Prospectus or any Time of Sale Information, it being understood and agreed that the only such information consists of the information identified in the Underwriting Agreement as being provided by the Underwriters.

(c) Notice and Procedures. If any suit, action, proceeding (including any governmental or regulatory investigation), claim or demand shall be brought or asserted against any person in respect of which indemnification may be sought pursuant to either paragraph (a) or (b) above, such person (the “Indemnified Person”) shall promptly notify the person against whom such indemnification may be sought (the “Indemnifying Person”) in writing; provided that the failure to notify the Indemnifying Person shall not relieve it from any liability that it may have under this Section 7 except to the extent that it has been materially prejudiced (through the forfeiture of substantive rights or defenses) by such failure; and provided, further, that the failure to notify the Indemnifying Person shall not relieve it from any liability that it may have to an Indemnified Person otherwise than under this Section 7. If any such proceeding shall be brought or asserted against an Indemnified Person and it shall have notified the Indemnifying Person thereof, the Indemnifying Person shall retain counsel reasonably satisfactory to the Indemnified Person to represent the Indemnified Person and any others entitled to indemnification pursuant to this Section 7 that the Indemnifying Person may designate in such proceeding and shall pay the fees and expenses of such counsel related to such proceeding as incurred. In any such proceeding, any Indemnified Person shall have the right to retain its own counsel, but the fees and expenses of such counsel shall be at the expense of such Indemnified Person unless (i) the Indemnifying Person and the Indemnified Person shall have mutually agreed to the contrary, (ii) the Indemnifying Person has failed within a reasonable time to retain counsel reasonably satisfactory to the Indemnified Person; (iii) the Indemnified Person shall have reasonably concluded that there may be legal defenses available to it that are different from or in addition to those available to the Indemnifying Person; or (iv) the named parties in any such proceeding (including any impleaded parties) include both the Indemnifying Person and the Indemnified Person and representation of both parties by the same counsel would be inappropriate due to actual or potential differing interests between them. It is

understood and agreed that the Indemnifying Person shall not, in connection with any proceeding or related proceeding in the same jurisdiction, be liable for the fees and expenses of more than one separate firm (in addition to any local counsel) for all Indemnified Persons, and that all such fees and expenses shall be reimbursed as they are incurred. Any such separate firm for any Underwriter, its affiliates, directors and officers and any control persons of such Underwriter shall be designated in writing by the Representative and any such separate firm for the Company, its directors, its officers who signed the Registration Statement and any control persons of the Company shall be designated in writing by the Company. The Indemnifying Person shall not be liable for any settlement of any proceeding effected without its written consent, but if settled with such consent or if there be a final judgment for the plaintiff, the Indemnifying Person agrees to indemnify each Indemnified Person from and against any loss or liability by reason of such settlement or judgment. Notwithstanding the foregoing sentence, if at any time an Indemnified Person shall have requested that an Indemnifying Person reimburse the Indemnified Person for fees and expenses of counsel as contemplated by this paragraph, the Indemnifying Person shall be liable for any settlement of any proceeding effected without its written consent if (i) such settlement is entered into more than 30 days after receipt by the Indemnifying Person of such request and (ii) the Indemnifying Person shall not have reimbursed the Indemnified Person in accordance with such request prior to the date of such settlement. No Indemnifying Person shall, without the written consent of the Indemnified Person, effect any settlement of any pending or threatened proceeding in respect of which any Indemnified Person is or could have been a party and indemnification could have been sought hereunder by such Indemnified Person, unless such settlement (x) includes an unconditional release of each Indemnified Person in form and substance reasonably satisfactory to such Indemnified Person from all liability on claims that are the subject matter of such proceeding and (y) does not include any statement as to or any admission of fault, culpability or a failure to act by or on behalf of any Indemnified Person.

(d) Contribution. If the indemnification provided for in paragraphs (a) and (b) above is unavailable to an Indemnified Person or insufficient in respect of any losses, claims, damages or liabilities referred to therein, then each Indemnifying Person under such paragraph, in lieu of indemnifying such Indemnified Person thereunder, shall contribute to the amount paid or payable by such Indemnified Person as a result of such losses, claims, damages or liabilities (i) in such proportion as is appropriate to reflect the relative benefits received by the Company on the one hand and the Underwriters on the other from the offering of the Securities or (ii) if the allocation provided by clause (i) is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) but also the relative fault of the Company on the one hand and the Underwriters on the other in connection with the statements or omissions that resulted in such losses, claims, damages or liabilities, as well as any other relevant equitable considerations. The relative benefits received by the Company on the one hand and the Underwriters on the other shall be deemed to be in the same respective proportions as the net proceeds (before deducting expenses) received by the Company from the sale of the Securities and the total underwriting discounts and commissions received by the Underwriters in

connection therewith, in each case as set forth in the table on the cover of the Prospectus, bear to the aggregate offering price of the Securities. The relative fault of the Company on the one hand and the Underwriters on the other shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Company or by the Underwriters and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

(e) Limitation on Liability. The Company and the Underwriters agree that it would not be just and equitable if contribution pursuant to this Section 7 were determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation that does not take account of the equitable considerations referred to in paragraph (d) above. The amount paid or payable by an Indemnified Person as a result of the losses, claims, damages and liabilities referred to in paragraph (d) above shall be deemed to include, subject to the limitations set forth above, any legal or other expenses incurred by such Indemnified Person in connection with any such action or claim. Notwithstanding the provisions of this Section 7, in no event shall an Underwriter be required to contribute any amount in excess of the amount by which the total underwriting discounts and commissions received by such Underwriter with respect to the offering of the Securities exceeds the amount of any damages that such Underwriter has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligations to contribute pursuant to this Section 7 are several in proportion to their respective purchase obligations hereunder and not joint.

(f) Non-Exclusive Remedies. The remedies provided for in this Section 7 are not exclusive and shall not limit any rights or remedies which may otherwise be available to any Indemnified Person at law or in equity.

8. Termination. This Agreement may be terminated in the absolute discretion of the Representative, by notice to the Company, if after the execution and delivery of this Agreement and prior to the Closing Date (i) trading generally shall have been suspended or materially limited on the New York Stock Exchange; (ii) trading of any securities issued or guaranteed by the Company shall have been suspended on any exchange (except on a temporary basis by Euronext pending an announcement by the Company); (iii) a general moratorium on commercial banking activities shall have been declared by federal or New York State authorities; or (iv) there shall have occurred any outbreak or escalation of hostilities or any change in financial markets or any calamity or crisis, either within or outside the United States, that, in the judgment of the Representative, is material and adverse and makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Securities on the terms and in the manner contemplated by this Agreement, the Time of Sale Information and the Prospectus.

9. Defaulting Underwriter. (a) If, on the Closing Date, any Underwriter defaults on its obligation to purchase the Securities that it has agreed to purchase hereunder, the non-defaulting Underwriters may in their discretion arrange for the purchase of such Securities by other persons satisfactory to the Company on the terms contained in this Agreement. If, within 36 hours after any such default by any Underwriter, the non-defaulting Underwriters do not arrange for the purchase of such Securities, then the Company shall be entitled to a further period of 36 hours within which to procure other persons satisfactory to the non-defaulting Underwriters to purchase such Securities on such terms. If other persons become obligated or agree to purchase the Securities of a defaulting Underwriter, either the non-defaulting Underwriters or the Company may postpone the Closing Date for up to five full business days in order to effect any changes that in the opinion of counsel for the Company or counsel for the Underwriters may be necessary in the Registration Statement and the Prospectus or in any other document or arrangement, and the Company agrees to promptly prepare any amendment or supplement to the Registration Statement and the Prospectus that effects any such changes. As used in this Agreement, the term “Underwriter” includes, for all purposes of this Agreement unless the context otherwise requires, any person not listed in the Underwriting Agreement that, pursuant to this Section 9, purchases Securities that a defaulting Underwriter agreed but failed to purchase.

(b) If, after giving effect to any arrangements for the purchase of the Securities of a defaulting Underwriter or Underwriters by the non-defaulting Underwriters and the Company as provided in paragraph (a) above, the aggregate principal amount of such Securities that remains unpurchased does not exceed one-eleventh of the aggregate principal amount of all the Securities, then the Company shall have the right to require each non-defaulting Underwriter to purchase the principal amount of Securities that such Underwriter agreed to purchase hereunder plus such Underwriter’s pro rata share (based on the principal amount of Securities that such Underwriter agreed to purchase hereunder) of the Securities of such defaulting Underwriter or Underwriters for which such arrangements have not been made.

(c) If, after giving effect to any arrangements for the purchase of the Securities of a defaulting Underwriter or Underwriters by the non-defaulting Underwriters and the Company as provided in paragraph (a) above, the aggregate principal amount of such Securities that remains unpurchased exceeds one-eleventh of the aggregate principal amount of all the Securities, or if the Company shall not exercise the right described in paragraph (b) above, then this Agreement shall terminate without liability on the part of the non-defaulting Underwriters. Any termination of this Agreement pursuant to this Section 9 shall be without liability on the part of the Company, except that the Company will continue to be liable for the payment of expenses as set forth in Section 10 hereof, and except that the provisions of Section 7 hereof shall not terminate and shall remain in effect.

(d) Nothing contained herein shall relieve a defaulting Underwriter of any liability it may have to the Company or any non-defaulting Underwriter for damages caused by its default.

10. Payment of Expenses. All expenses incident to the performance of each party’s obligations under this Agreement shall be paid in the manner specified in the Underwriting Agreement.

11. Persons Entitled to Benefit of Agreement. This Agreement shall inure to the benefit of and be binding upon the parties hereto and their respective successors and the officers and directors and any controlling persons referred to herein, and the affiliates of each Underwriter referred to in Section 7 hereof. Nothing in this Agreement is intended or shall be construed to give any other person any legal or equitable right, remedy or claim under or in respect of this Agreement or any provision contained herein. No purchaser of Securities from any Underwriter shall be deemed to be a successor merely by reason of such purchase.

12. Survival. The respective indemnities, rights of contribution, representations, warranties and agreements of the Company and the Underwriters contained in this Agreement or made by or on behalf of the Company or the Underwriters pursuant to this Agreement or any certificate delivered pursuant hereto shall survive the delivery of and payment for the Securities and shall remain in full force and effect, regardless of any termination of this Agreement or any investigation made by or on behalf of the Company or the Underwriters.

13. Certain Defined Terms. For purposes of this Agreement, (a) except where otherwise expressly provided, the term “affiliate” has the meaning set forth in Rule 405 under the Securities Act; (b) the term “business day” means any day other than a day on which banks are permitted or required to be closed in New York City; and (c) the term “subsidiary” has the meaning set forth in Rule 405 under the Securities Act.

For the purposes of this Agreement, “Principal Subsidiary” means at any relevant time a Subsidiary of the Company:

(i) Whose total revenues (or, where the Subsidiary in question prepares consolidated financial statements, whose total consolidated revenues) attributable to the Company and its consolidated subsidiaries represent not less than 5 percent of the total consolidated revenues of the Company and its consolidated subsidiaries, all as calculated by reference to the then latest audited financial statements (or consolidated financial statements, as the case may be) of such Subsidiary and the then latest consolidated financial statements of the Company and its consolidated subsidiaries; or

(ii) To which is transferred all or substantially all the assets and undertakings of a Subsidiary which immediately prior to such transfer is a Principal Subsidiary.

For the purpose of the definition of “Principal Subsidiary,” “Subsidiary” means, in relation to any person or entity at any time, any other person or entity (whether or not now existing) meeting the definition of Article L.233-1 of the French Commercial Code or any other person or entity controlled directly or indirectly by such person or entity within the meaning of Article L.233-3 of the French Commercial Code.

14. Miscellaneous. (a) Authority of the Representative. Any action by the Underwriters hereunder may be taken by the Representative on behalf of the Underwriters, and any such action taken by the Representative shall be binding upon the Underwriters.

(b) Notices. All notices and other communications hereunder shall be in writing and shall be deemed to have been duly given if mailed or transmitted and confirmed by any standard form of telecommunication. Notices to the Underwriters shall be given to the Representative at the address set forth in the Underwriting Agreement. Notices to the Company shall be given to it at 61, rue des Belles Feuilles, 75116 Paris, France, Attention: Michel Bisiaux, or if different, to the address set forth in the Underwriting Agreement.

Annex A

[Form of Underwriting Agreement]

Underwriting Agreement

, 200___

[Name(s) of Representative(s)]

As Representative(s) of the
several Underwriters listed
in Schedule 1 hereto

c/o [Name(s) and Address(es) of Representative(s)]

Ladies and Gentlemen:

Lafarge S.A., a société anonyme organized under the laws of the Republic of France (the “Company”), proposes to issue and sell to the several Underwriters listed in Schedule 1 hereto (the “Underwriters”), for whom you are acting as representative (the “Representative”), $ principal amount of its ___% Notes due 20___ having the terms set forth in Schedule 2 hereto (the “Securities”). The Securities will be issued pursuant to an Indenture [to be] dated as of , 200___ (the “Indenture”) between the Company and Law Debenture Trust Company of New York, as trustee (the “Trustee”).

Subject to the terms and conditions and in reliance upon the representations and warranties herein set forth, the Company agrees to issue and sell the Securities to the several Underwriters named in the Underwriting Agreement, and each Underwriter, subject to the terms and conditions and in reliance upon the representations and warranties herein set forth, agrees, severally and not jointly, to purchase from the Company the respective principal amount of Securities set forth opposite such Underwriter’s name in Schedule 1 hereto at a price equal to ___% of the principal amount thereof plus accrued interest, if any, from , 200___ to the Closing Date (as defined below). The Company will not be obligated to deliver any of the Securities except upon payment for all the Securities to be purchased as provided herein.

The Company understands that the Underwriters intend to make a public offering of the Securities as soon after the effectiveness of this Agreement as in the judgment of the Representative is advisable, and initially to offer the Securities on the terms set forth in the Time of Sale Information and the Prospectus. Schedule 3 hereto sets forth

A-1

Annex A

information that together with (i) the Basic Prospectus, as amended and supplemented to the date of the Underwriting Agreement, and (ii) the Preliminary Prospectus used most recently prior to the execution of the Underwriting Agreement, constitute the Time of Sale Information made available at the Time of Sale. The Company acknowledges and agrees that the Underwriters may offer and sell Securities to or through any affiliate of an Underwriter and that any such affiliate may offer and sell Securities purchased by it to or through any Underwriter.

Payment for and delivery of the Securities shall be made at the offices of Davis Polk & Wardwell, [450 Lexington Avenue, New York, NY 10017] at [10:00 A.M.], [New York City] time, on , 200___, or at such other time or place on the same or such other date, not later than the fifth business day thereafter, as the Representative and the Company may agree upon in writing.

Payment for the Securities shall be made by wire transfer in immediately available funds to the account(s) specified by the Company to the Representative against delivery to the nominee of The Depository Trust Company, for the account of the Underwriters, of one or more global notes representing the Securities (collectively, the “Global Note”), with any transfer taxes payable in connection with the sale of the Securities duly paid by the Company. [The Global Note will be made available for inspection by the Representative not later than 1:00 P.M., New York City time, on the business day prior to the Closing Date.]

The Company and the Underwriters acknowledge and agree that the only information relating to any Underwriter that has been furnished to the Company in writing by any Underwriter through the Representative expressly for use in the Registration Statement, the Prospectus (or any amendment or supplement thereto) any Issuer Free Writing Prospectus or any Time of Sale Information and [any Preliminary Prospectus] consists of the following: [insert references to appropriate paragraphs] [and the following information in the Issuer Free Writing Prospectus dated , 20 ; [insert description of information provided by Underwriters]].

[Payment of Expenses]

[Other than as set forth in the following paragraph,][a][A]ll provisions contained in the document entitled Lafarge Debt Securities Underwriting Agreement Standard Provisions are incorporated by reference herein in their entirety and shall be deemed to be a part of this Underwriting Agreement to the same extent as if such provisions had been set forth in full herein, except that if any term defined in such Underwriting Agreement Standard Provisions is otherwise defined herein, the definition set forth herein shall control.

[Qualifications to Any Covenants or Representations Made by the Company]

A-2

Annex A

Schedule 4

[Form for Debt]

LAFARGE

Pricing Term Sheet


Issuer:
Size:		$
Maturity:		___, 20___
Coupon:		%
Price:		% of face amount
Yield to maturity:		%
Interest Payment Dates:		and , commencing , 2006
Redemption Provisions:

Settlement:		T+_; , 200___
[CUSIP:		]
[Ratings:		]

Note: A securities rating is not a recommendation to buy, sell or hold securities and may be subject to revision or withdrawal at any time.

The issuer has filed a registration statement (including a prospectus) with the SEC for the offering to which this communication relates. Before you invest, you should read the prospectus in that registration statement and other documents the issuer has filed with the SEC for more complete information about the issuer and this offering. You may get these documents for free by visiting EDGAR on the SEC Web site at www.sec.gov. Alternatively, the issuer, any underwriter or any dealer participating in the offering will arrange to send you the prospectus if you request it by calling toll-free 1-8[xx-xxx-xxxx] [or emailing [ ] at [ ] ].

A-8

Annex B

Opinion of Cleary Gottlieb Steen & Hamilton LLP,
Special French Counsel to the Company

We have acted as special French counsel to Lafarge, S.A., a société anonyme organized under the laws of the French Republic (the “Company”), in connection with the Company’s offering pursuant to a registration statement on Form F-3 (No. 333-135665) of [to be completed with titles of notes] (the “Securities”) to be issued under an indenture dated as of July 18, 2006 (the “Indenture”) between the Company and Law Debenture Trust Company of New York, as trustee (the “Trustee”). Such registration statement, as amended as of its most recent effective date ([insert date]) determined pursuant to Rule 430B(f)(2) under the Securities Act of 1933, as amended (the “Securities Act”), but excluding the documents incorporated by reference therein, is herein called the “Registration Statement”; the related prospectus dated July 10, 2006, included therein, but excluding the documents incorporated by reference therein, is herein called the “Base Prospectus”; the preliminary prospectus supplement dated [insert date], as filed with the Commission pursuant to Rule 424(b)(2) under the Securities Act, but excluding the documents incorporated by reference therein, is herein called the “Preliminary Prospectus Supplement”; and the related prospectus supplement dated [insert date], as first filed with the Commission pursuant to Rule 424(b)([2]) under the Securities Act, but excluding the documents incorporated by reference therein, is herein called the “Final Prospectus Supplement”. The Base Prospectus and the Preliminary Prospectus Supplement are together herein called the “Pricing Prospectus”, and the Base Prospectus and the Final Prospectus Supplement are herein called the “Final Prospectus”.

This opinion letter is furnished pursuant to Section 6(g) of the underwriting agreement dated [insert date] (the “Underwriting Agreement”) between the Company and the several underwriters named in Schedule 1 thereto (the “Underwriters”).

In arriving at the opinions expressed below, we have reviewed the following documents:

	(A)		an executed copy of the Underwriting Agreement;

	(B)		an executed copy of the Indenture;

	(C)		the Securities in global form as executed by the Company and authenticated by the Trustee;

	(D)		the Pricing Prospectus and the documents incorporated by reference therein;

B-1

Annex B

	(E)		the Final Prospectus and the documents incorporated by reference therein;

	(F)		a certified copy of the statuts of the Company in effect as of the date hereof;

	(G)		an extract of information (extrait K-bis) from the registry of commerce and companies (Registre du commerce et des sociétés) of Paris dated as of [insert date] with respect to the Company;

	(H)		an executed copy of the decision, dated [insert date], of Bruno Lafont, the Directeur Général of the Company;

	(I)		a certified copy of the resolution of the board of directors of the Company dated December 16, 2005; and

	(J)		an officer’s certificate executed by Michel Bisiaux as Corporate Secretary of the Company.

In addition, we have reviewed the originals or copies certified or otherwise identified to our satisfaction of all such corporate records of the Company and such other instruments and other certificates of public officials, officers and representatives of the Company and such other persons, and we have made such investigations of law, as we have deemed appropriate as a basis for the opinions expressed below.

In rendering the opinions expressed below, we have assumed the authenticity of all documents submitted to us as originals and the conformity to the originals of all documents submitted to us as copies. In addition, we have assumed and have not verified the accuracy as to factual matters of each document we have reviewed (including, without limitation, the accuracy of the representations and warranties of the Company in the Underwriting Agreement).

The opinions below are given solely on the basis of the laws of the French Republic as currently in effect, and we have made no investigation of any other laws which may be relevant to the Underwriting Agreement, the Indenture and the Securities or the opinions below (except as described in our opinion letter relating to New York and United States law of even date herewith).

On the basis of and subject to the foregoing, and subject to the qualifications set forth below, it is our opinion that:

The Company is validly existing as a société anonyme under the laws of the French Republic.

B-2

Annex B

	2.		The Company has corporate power to enter into the Underwriting Agreement, the Indenture and the Securities and to perform its obligations thereunder.

	3.		The execution by the Company of the Underwriting Agreement and the Indenture and the issue of the Securities and the performance of their respective obligations thereunder, have been duly authorized by all necessary corporate action of the Company.

	4.		The Underwriting Agreement, the Indenture and the Securities have been duly executed by the Company under the laws of the French Republic.

	5.		The execution by the Company of the Underwriting Agreement and the Indenture and the issue and sale of the Securities will not result in any breach or violation by the Company of any of the terms and provisions of the statuts of the Company or in any violation by the Company of any published law or regulation of the French Republic of general application.

	6.		The choice of the law of the State of New York to govern the Underwriting Agreement, the Indenture and the Securities is valid under the laws of the French Republic, and a French court would uphold such choice of law in any proceedings on the Underwriting Agreement, the Indenture or the Securities brought before it, provided that the relevant content of New York law is duly proved in any such proceedings and that the application of New York law (i) is not found to be contrary to mandatory provisions of the laws of any jurisdiction presenting a close connection with the transaction, which under the laws of such jurisdiction are applicable irrespective of the law governing the Underwriting Agreement, the Indenture or the Securities (lois de police), (ii) is not found to be contrary to a provision of French law whose application to the situation is found mandatory irrespective of the law governing the Underwriting Agreement, the Indenture or the Securities (lois de police) and (iii) is not found to be manifestly contrary to a provision of French public policy (ordre public).

	7.		The submission by the Company to the exclusive jurisdiction of the United States federal courts located in the Borough of Manhattan or the courts of the State of New York located in the Borough of Manhattan with respect to any action or proceeding arising out of or

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Annex B

			relating to the Underwriting Agreement, the Indenture or the Securities is legal, valid and binding.

	8.		A judgment in respect of the Agreement that is final, conclusive and enforceable in New York, United States of America, would be recognized and enforced by the courts of France without a review of the merits through a procedure known as action en exequatur, provided that (a) procedural rules applicable to the action en exequatur are met and (b) the French court in which enforcement is sought determines that:

	(i)		fundamental procedural rights were duly observed by the court rendering the judgment;

	(ii)		the laws of the State of New York were applied by the court rendering the judgment; and

	(iii)		the judgment is not contrary to French public policy (ordre public) and is not tainted by fraud, as both concepts are defined in the context of enforcement of foreign judgments.

	9.		The execution by the Company of the Underwriting Agreement and the Indenture and the offer and sale of the Securities in the manner contemplated in the Underwriting Agreement do not require any consent, approval, authorization, registration, filing or qualification of or with any governmental or administrative authority of the French Republic.

	10.		No French registration, capital, stamp, transfer taxes, customs or other duties or taxes of any kind are applicable to any of the acts or transactions involved in the issue and offering of the Securities, the subscription thereof or the transfer of the Securities, to the extent that such transfer takes place between persons who are non-residents for French tax purposes and provided that the payment of expenses and commissions due pursuant to the Underwriting Agreement and the Indenture shall be subject to applicable tax laws, in particular with respect to value-added tax.

	11.		The Securities will rank pari passu with the Company’s other unsecured and unsubordinated indebtedness, except with respect to indebtedness mandatorily preferred by law.

In rendering our opinion expressed in paragraph 1 above, we have relied without independent investigation solely on the (F), (G) and (J) above. In

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Annex B

rendering our opinions in paragraphs 2, 3 and 4 above, we have relied without independent investigation solely on the documents referred to in items (F), (G), (H), (I), and (J) above.

Insofar as the foregoing opinions relate to the validity, binding effect or enforceability of any agreement or obligation of the Company, (a) we have assumed that the Company and each other party to such agreement or obligation has satisfied those legal requirements that are applicable to it to the extent necessary to make such agreement or obligation enforceable against it (except that no such assumption is made as to the Company regarding matters of the law of the French Republic), and (b) such opinions are subject to applicable bankruptcy, insolvency and similar laws affecting creditors’ rights generally and to general principles of equity.

We express no opinion as to the availability of the remedy of specific enforcement or any remedies other than those culminating in a judgment for the payment of money.

In respect of any payment obligation under the Underwriting Agreement, the Indenture and the Securities, we note that French courts have power under Article 1244-1 of the French Civil Code, up to a two-year limit, to defer or otherwise reschedule payment dates, taking into account the debtor’s financial position and the creditors’ financial needs. French courts may also decide that any amount, the payment date of which is thus deferred or rescheduled, will bear interest at a rate lower than the contractual rate and/or that any payment made shall first be allocated towards repayment of the principal. A French court may subject such decision to the furnishing of security by the debtor in respect of its debt.

We express no opinion as to the currency in which a French court would order payment of an amount due pursuant to the Underwriting Agreement, the Indenture or the Securities. A foreign currency judgment may be subject to conversion into euros at a rate of exchange prevailing other than on the date of actual payment.

Under Article 1152 of the French Civil Code, French courts have discretion to increase or decrease the amount of any damages, indemnities or penalties provided for in the Underwriting Agreement to the extent they would deem them clearly excessive or insufficient, as the case may be.

We note that (a) prior to admitting any agreement into evidence or enforcing the judgment of a foreign court based on any agreement, a French court may require the translation of such agreement or judgment into French by a sworn translator (traducteur assermenté) and (b) a French court might not enforce the provisions of the Underwriting Agreement, the Indenture or the

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Annex B

Securities requiring parties thereto to indemnify other parties or third parties for court costs and legal fees.

Certain provisions of the Underwriting Agreement, the Indenture or the Securities pursuant to which a determination or certificate is to be held final, conclusive or binding might not be enforced by French courts if such determination or certification could be shown to have an unreasonable, incorrect or arbitrary basis or not to have been given or made in good faith.

A conditional obligation arising under an agreement may not be enforced by a French court if the determination as to whether the condition has been satisfied is left to the discretionary power of the obligor since such condition could be considered purement potestative. If such purement potestative condition were considered to be an essential obligation of the agreement, such agreement may itself be considered invalid notwithstanding any provision to the contrary.

We express no opinion as to the validity or enforceability in France or before a French court of any provisions of the Underwriting Agreement, the Indenture or the Securities which require increased payments in respect of any withholding or deduction required under the laws of France.

We are rendering this opinion in our capacity as Avocats au Barreau de Paris, and we do not purport to express any opinion herein concerning any law other than the laws of the French Republic as in effect on the date hereof.

We are furnishing this opinion letter to you, as representatives of the Underwriters, solely for the benefit of the Underwriters in their capacity as such in connection with the offering of the Securities. This opinion letter is not to be relied on by or furnished to any other person or used, circulated, quoted or otherwise referred to for any other purpose, except that this opinion letter may be relied upon by the Trustee in its capacity as such. We assume no obligation to advise you or any other person, or to make any investigations, as to any legal developments or factual matters arising subsequent to the date hereof that might affect the opinions expressed herein.

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Annex B

Opinion of Cleary Gottlieb Steen & Hamilton LLP,
Special U.S. Counsel to the Company

We have acted as special U.S. counsel to Lafarge, S.A., a société anonyme organized under the laws of the French Republic (the “Company”), in connection with the Company’s offering pursuant to a registration statement on Form F-3 (No. 333-135665) of [to be completed with titles of notes] (the “Securities”) to be issued under an indenture dated as of July 18, 2006 (the “Indenture”) between the Company and Law Debenture Trust Company of New York, as trustee (the “Trustee”). Such registration statement, as amended as of its most recent effective date ([insert date]) determined pursuant to Rule 430B(f)(2) under the Securities Act of 1933, as amended (the “Securities Act”), but excluding the documents incorporated by reference therein, is herein called the “Registration Statement”; the related prospectus dated July 10, 2006, included therein, but excluding the documents incorporated by reference therein, is herein called the “Base Prospectus”; the preliminary prospectus supplement dated [insert date], as filed with the Securities and Exchange Commission (the “Commission”) pursuant to Rule 424(b)(2) under the Securities Act, but excluding the documents incorporated by reference therein, is herein called the “Preliminary Prospectus Supplement”; and the related prospectus supplement dated [insert date], as first filed with the Commission pursuant to Rule 424(b)([2]) under the Securities Act, but excluding the documents incorporated by reference therein, is herein called the “Final Prospectus Supplement”. The Base Prospectus and the Preliminary Prospectus Supplement are together herein called the “Pricing Prospectus”, and the Base Prospectus and the Final Prospectus Supplement are together herein called the “Final Prospectus”.

In arriving at the opinions expressed below, we have reviewed the following documents:

(i)		an executed copy of the Underwriting Agreement;

(ii)		the Registration Statement and the documents incorporated by reference therein;

(iii)		the Pricing Prospectus and the documents incorporated by reference therein and the documents listed in Schedule I hereto;

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Annex B

(iv)		the Final Prospectus and the documents incorporated by reference therein;

(v)		the Securities in global form as executed by the Company and authenticated by the Trustee;

(vi)		an executed copy of the Indenture; and

(vii)		the documents delivered to you by the Company at the closing pursuant to the Underwriting Agreement.

Based on the foregoing, and subject to the further assumptions and qualifications set forth below, it is our opinion that:

1. The Indenture is a valid, binding and enforceable agreement of the Company.

2. The Securities, when duly paid for and delivered in accordance with the Underwriting Agreement, will constitute a valid, binding and enforceable obligation of the Company.

3. The execution and delivery by the Company of the Underwriting Agreement and the Indenture do not, and the issuance and sale of the Securities to the Underwriters pursuant to the terms of the Underwriting Agreement and the performance by the Company of its obligations in each of the Underwriting Agreement, the Indenture and the Securities will not, (a) require any consent, approval, authorization, registration or qualification of or with any governmental authority of the United States of America or the State of New York that in our experience is normally applicable to general business entities with respect to such execution, delivery, issuance, sale or performance (but we express no opinion with respect to the United States federal securities laws or any state

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Annex B

securities or Blue Sky laws) or (b) result in a violation of any United States federal or New York State law or published rule or regulation that in our experience is normally applicable to general business entities with respect to such execution, delivery, issuance, sale or performance (but we express no opinion with respect to the United States federal securities laws or any state securities or Blue Sky laws).

4. The Company is not an “investment company” subject to the registration requirements of the U.S. Investment Company Act of 1940, as amended.

Insofar as the foregoing opinions relate to the validity, binding effect or enforceability of any agreement or obligation of the Company, (a) we have assumed that the Company and each other party to such agreement or obligation has satisfied or, prior to the issuance of Securities, will satisfy those legal requirements that are applicable to it to the extent necessary to make such agreement or obligation enforceable against it (except that no such assumption is made as to the Company regarding matters of the federal law of the United States of America or the law of the State of New York that in our experience would normally be applicable to general business entities with respect to such agreement or obligation), (b) such opinions are subject to applicable bankruptcy, insolvency and similar laws affecting creditors’ rights generally and to general principles of equity and (c) such opinions are subject to the effect of judicial application of foreign laws or foreign governmental actions affecting creditors’ rights.

We note that (i) provisions in any agreement by which a party submits to the general jurisdiction of the courts of the State of New York or the U.S. federal courts located in the Borough of Manhattan are subject to the applicable limitations on the competent jurisdiction of such courts; and (ii) we express no opinion as to the subject matter jurisdiction of any U.S. federal court to adjudicate any action between two parties neither of which is a citizen of any U.S. state for purposes of 28 U.S.C. §1332.

We note that the designation under the Indenture of the courts of the State of New York or the U.S. federal courts located in the Borough of Manhattan as the venue for actions or proceedings with respect thereto or any proceeding to execute or otherwise enforce any judgment in respect of any breach thereof (notwithstanding the waiver therein) is subject to the power of such courts to transfer actions pursuant to 28 U.S.C. §1404(a) or to dismiss such actions or proceedings on the ground that such a federal court is an inconvenient forum for such an action or proceeding.

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Annex B

Negative Comfort Letter of Cleary Gottlieb Steen & Hamilton LLP,
Special U.S. Counsel to the Company

This letter is furnished pursuant to Section 6(g) of the underwriting agreement dated [insert date] (the “Underwriting Agreement”) between the Company and the several underwriters named in Schedule 1 thereto (the “Underwriters”).

Because the primary purpose of our professional engagement was not to establish or confirm factual matters or financial, accounting or statistical information, and because many determinations involved in the preparation of the Registration Statement, the Pricing Prospectus, the Final Prospectus, the documents incorporated by reference therein and the documents listed in Schedule I hereto are of a wholly or partially non-legal character or relate to legal matters outside the scope of our opinion letter to you of even date herewith, we are not passing upon and do not assume any responsibility for the accuracy, completeness or fairness of the statements contained in the Registration Statement, the Pricing Prospectus, the Final Prospectus, the documents incorporated by reference therein, or the documents listed in Schedule I hereto and we make no representation that we have independently verified the

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Annex B

accuracy, completeness or fairness of such statements. We also are not passing upon and do not assume any responsibility for ascertaining whether or when any of the Pricing Prospectus, the Final Prospectus, the documents incorporated by reference therein or the documents listed in Schedule I hereto was conveyed to any person for purposes of Rule 159 under the Securities Act.

However, in the course of our acting as special United States counsel to the Company in connection with its preparation of the Registration Statement, the Pricing Prospectus, the Final Prospectus and the documents listed in Schedule I hereto, we participated in conferences and telephone conversations with representatives of the Company, representatives of the independent public accountants for the Company, your representatives and representatives of your counsel, during which conferences and conversations the contents of the Registration Statement, the Pricing Prospectus, the Final Prospectus, portions of certain of the documents incorporated by reference therein and the documents listed in Schedule I hereto and related matters were discussed, and we reviewed certain corporate records and documents furnished to us by the Company.

Based on our participation in such conferences and conversations and our review of such records and documents as described above, our understanding of the U.S. federal securities laws and the experience we have gained in our practice thereunder, we advise you that:

(a) The Registration Statement, including the documents incorporated by reference therein (except the financial statements and schedules and other financial and statistical data included therein and management’s report on the effectiveness of internal control over financial reporting incorporated therein by reference, as to which we express no view), as of its most recent effective date ([insert date]) determined pursuant to Rule 430B(f)(2), and the Final Prospectus (except as aforesaid), as of the date thereof, appeared on their face to be appropriately responsive in all material respects to the requirements of the Securities Act and the Trust Indenture Act of 1939, as amended, and the rules and regulations thereunder. In addition, we do not know of any contracts or other documents of a character required to be filed as exhibits to the Registration Statement or required to be described in the Registration Statement or the Final Prospectus that are not filed or described as required.

(b) No information has come to our attention that causes us to believe that the Registration Statement, including the documents incorporated by reference therein (except the financial statements and schedules and other financial and statistical data included therein and management’s report on the effectiveness of internal control over financial reporting incorporated therein by reference, as to which we express no view), as of its most recent effective date

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Annex B

([insert date]) determined pursuant to Rule 430B(f)(2), contained an untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary to make the statements therein not misleading.

(c) No information has come to our attention that causes us to believe that the Pricing Prospectus, including the documents incorporated by reference therein, considered together with the amount and the price to the public of the Securities on the front cover of the Final Prospectus and the statements under the headings “Prospectus Supplement Summary – The Offering” and “Description of Notes” in the Final Prospectus and the documents listed on Schedule I hereto (except in each case the financial statements and schedules and other financial and statistical data included in the Pricing Prospectus and management’s report on the effectiveness of internal control over financial reporting incorporated therein by reference, as to which we express no view), at the time of execution of the Underwriting Agreement, contained an untrue statement of a material fact or omitted to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(d) No information has come to our attention that causes us to believe that the Final Prospectus, including the documents incorporated by reference therein (except the financial statements and schedules and other financial and statistical data included therein and management’s report on the effectiveness of internal control over financial reporting incorporated therein by reference, as to which we express no view), as of the date thereof or hereof, contained or contains an untrue statement of a material fact or omitted or omits to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading.

We confirm to you that (based solely upon a telephonic confirmation from a representative of the Commission) the Registration Statement is effective under the Securities Act and no stop order with respect thereto has been issued, and, to the best of our knowledge, no proceeding for that purpose has been instituted or threatened, by the Commission.

We are furnishing this letter to you, as representatives of the Underwriters, solely for the benefit of the Underwriters in their capacity as such in connection with the offering of the Securities. This letter is not to be relied on by or furnished to any other person or used, circulated, quoted or otherwise referred to for any other purpose. We assume no obligation to advise you, or to make any investigations, as to any legal developments or factual matters arising subsequent to the date hereof that might affect the opinions expressed herein.

Schedule I
Schedule 4 to the Underwriting Agreement

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Annex C

Opinion of Michel Bisiaux,
Internal Legal Counsel to the Company

I have acted as internal legal counsel to Lafarge S.A., a société anonyme organized under the laws of the French Republic (the “Company”) in connection with the Company’s offering pursuant to a registration statement on Form F-3 (No. 333-135665) of [to be completed with titles of notes] (the “Securities”) to be issued under an indenture dated as of July 18, 2006 (the “Indenture”) between the Company and Law Debenture Trust Company of New York, as trustee (the “Trustee”). Such registration statement, as amended as of its most recent effective date ([insert date]) determined pursuant to Rule 430B(f)(2) under the Securities Act of 1933, as amended (the “Securities Act”), including the documents incorporated by reference therein, is herein called the “Registration Statement”; the related prospectus dated July 10, 2006, included therein, including the documents incorporated by reference therein, is herein called the “Base Prospectus”; the preliminary prospectus supplement dated [insert date], as filed with the Securities and Exchange Commission (the “Commission”) pursuant to Rule 424(b)(2) under the Securities Act, including the documents incorporated by reference therein, is herein called the “Preliminary Prospectus Supplement”; and the related prospectus supplement dated [insert date], as first filed with the Commission pursuant to Rule 424(b)([2]) under the Securities Act, including the documents incorporated by reference therein, is herein called the “Final Prospectus Supplement”. The Base Prospectus and the Preliminary Prospectus Supplement are together herein called the “Pricing Prospectus”, and the Base Prospectus and the Final Prospectus Supplement are together herein called the “Final Prospectus”.

This opinion letter is furnished pursuant to Section 6(h) of the underwriting agreement dated [insert date] (the “Underwriting Agreement”) between the Company and the several underwriters named in Schedule 1 thereto (the “Underwriters”).

In arriving at the opinions expressed below, as at the date mentioned on the first page hereof, I have reviewed the following documents:

	(A)		an executed copy of the Underwriting Agreement;

	(B)		an executed copy of the Indenture;

	(C)		the Securities in global form as executed by the Company and authenticated by the Trustee;

	(D)		the Pricing Prospectus;

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Annex C

	(E)		the Final Prospectus;

	(F)		a certified copy of the statuts of the Company in effect as of the date hereof;

	(G)		an executed copy of the decision, dated [insert date], of Bruno Lafont, the Directeur Général of the Company;

	(H)		a certified copy of the resolution of the board of directors of the Company dated December 16, 2005;

	(I)		an officer’s certificate executed by Michel Bisiaux as Corporate Secretary of the Company; and

	(J)		an Extrait K-bis of the Registre du Commerce of Paris, dated [insert date] relating to the Company.

In addition, I have reviewed the originals or copies certified or otherwise identified to my satisfaction of all such corporate records of the Company and such other instruments and other certificates of public officials, officers and representatives of the Company, and I have made such investigations of law, as I have deemed appropriate as a basis for the opinions expressed below.

In rendering the opinions expressed below, I have assumed the authenticity of all documents submitted to me as originals and the conformity to the originals of all documents submitted to me as copies.

The opinions below are given solely on the basis of the laws of the French Republic as currently in effect, and I have made no investigation of any other laws which may be relevant to the agreements or the opinions below.

On the basis of and subject to the foregoing, it is my opinion that:

1. The Underwriting Agreement, the Indenture and the Securities have been duly authorized and executed by the Company.

2. No litigation or arbitration proceedings or other proceedings before a competent governmental authority are pending, or to the best of my knowledge threatened, against the Company or any of its subsidiaries, the effect of which in case of an adverse determination would be to impact adversely the ability of the Company to perform its obligations under the Underwriting Agreement, the Indenture or the Securities, except as otherwise disclosed in the Final Prospectus.

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Annex C

3. The execution of the Underwriting Agreement and the Indenture and the issue of Securities against payment to the Company of the consideration agreed therefore in accordance with such agreements will not result in a breach under the terms of any credit agreement, financial instrument or other material contract to which the Company is a party, which breach would reasonably be expected to have a material adverse effect on the condition (financial or otherwise), or operations of the Company or the ability of the Company to perform its obligations under the Underwriting Agreement, the Indenture or the Securities.

I am furnishing this opinion letter to you, as representatives of the Underwriters, solely for the benefit of the Underwriters in their capacity as such in connection with the offering of the Securities. This opinion letter is not to be relied on by or furnished to any other person or used, circulated, quoted or otherwise referred to for any other purpose, except that this opinion letter may be relied upon by the Trustee in its capacity as such. I assume no obligation to advise you or any other person, or to make any investigations, as to any legal developments or factual matters arising subsequent to the date hereof that might affect the opinions expressed herein.

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		Very truly yours,

		LAFARGE

		By
		Title:


Underwriter		Principal Amount
		$


	Total	$