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</LabelSeparator><Level>2</Level><ElementName>us-gaap_OrganizationConsolidationBasisOfPresentationBusinessDescriptionAndAccountingPoliciesTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><PreferredLabelRole>terseLabel</PreferredLabelRole><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="D2013Q2YTD" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;div style="font-family:Times New Roman;font-size:10pt;"&gt;&lt;table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"&gt;&lt;tr&gt;&lt;td style="width:36px;" rowspan="1" colspan="1"&gt;&lt;/td&gt;&lt;td rowspan="1" colspan="1"&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td style="vertical-align:top" rowspan="1" colspan="1"&gt;&lt;div style="line-height:120%;font-size:10pt;padding-left:0px;"&gt;&lt;font style="font-family:inherit;font-size:10pt;font-weight:bold;text-align:left;"&gt;&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td style="vertical-align:top;" rowspan="1" colspan="1"&gt;&lt;div style="line-height:120%;text-align:left;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;font-weight:bold;text-align:left;"&gt;Basis of Presentation&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&amp;#160;&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;div style="line-height:120%;text-align:justify;padding-left:48px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;padding-left:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;Nortek, Inc. (&amp;#8220;Nortek&amp;#8221;) and all of its wholly owned subsidiaries, collectively the &amp;#8220;Company,&amp;#8221; is a global, diversified company whose many market-leading brands deliver broad capabilities and a wide array of innovative, technology-driven products and solutions for lifestyle improvement at home and at work. Operating within &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;five&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; reporting segments (see Note J, &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;font-style:italic;"&gt;&amp;#8220;Segment Information&amp;#8221;&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;), the Company manufactures and sells, primarily in the United States, Canada and Europe, with additional manufacturing in China, a wide variety of products for the remodeling and replacement markets, the residential and commercial new construction markets, the manufactured housing market, and the personal and enterprise computer markets.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;padding-left:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;padding-left:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;The Company operates on a calendar year, and each interim period is comprised of two 4-week periods and one 5-week period, with each week ending on a Saturday. The Company's fiscal year always begins on January 1 and ends on December 31.  As a result, the Company's first and fourth quarters may have more or less days included than a traditional 4-4-5 fiscal calendar, which consists of 91 days. The three months ended &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;color:#000000;text-decoration:none;"&gt;June&amp;#160;29, 2013&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; (&amp;#8220;&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;color:#000000;text-decoration:none;"&gt;second&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; quarter of 2013&amp;#8221;) and &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;color:#000000;text-decoration:none;"&gt;June&amp;#160;30, 2012&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; (&amp;#8220;&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;color:#000000;text-decoration:none;"&gt;second&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; quarter of 2012&amp;#8221;) each include &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;91&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; days.  The first six months ended &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;color:#000000;text-decoration:none;"&gt;June&amp;#160;29, 2013&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; ("first half of 2013") and &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;color:#000000;text-decoration:none;"&gt;June&amp;#160;30, 2012&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; ("first half of 2012") include &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;color:#000000;text-decoration:none;"&gt;180&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; days and &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;color:#000000;text-decoration:none;"&gt;182&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; days, respectively.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;padding-left:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;padding-left:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;The accompanying unaudited condensed consolidated financial statements reflect the financial position, results of operations, comprehensive income (loss), and cash flows of the Company after elimination of intercompany accounts and transactions, without audit and, in the opinion of management, reflect all adjustments of a normal recurring nature necessary for a fair statement of the interim periods presented. Although certain information and footnote disclosures normally included in annual financial statements prepared in accordance with U.S. generally accepted accounting principles ("U.S. GAAP") have been omitted, the Company believes that the disclosures included are adequate to make the information presented herein not misleading. Operating results for the &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;color:#000000;text-decoration:none;"&gt;second&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; quarter and first half of 2013 and 2012 are not necessarily indicative of the results that may be expected for other interim periods or for any fiscal year. Certain amounts in the prior year's unaudited condensed consolidated financial statements have been reclassified to conform to the current period presentation.  &lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;padding-left:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;padding-left:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;These unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the related notes included in the Company's annual report on Form 10-K for the fiscal year ended December 31, 2012 ("2012 Form 10-K") and Current Reports on Form 8-K as filed with the Securities and Exchange Commission ("SEC").&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;padding-left:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;padding-left:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;font-weight:bold;"&gt;New Accounting Pronouncements&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;padding-left:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;padding-left:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;In February 2013, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2013-04, &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;font-style:italic;"&gt;Liabilities&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; (&amp;#8220;ASU 2013-04&amp;#8221;), which is intended to provide guidance for the recognition, measurement, and disclosure of obligations resulting from joint and several liability arrangements for which the total amount of the obligation is fixed at the reporting date, except for obligations addressed within existing guidance in U.S. GAAP.  ASU 2013-04 requires an entity to measure obligations resulting from joint and several liability arrangements for which the total amount of the obligation is fixed at the reporting date as the sum of a) the amount the reporting entity agreed to pay on the basis of its arrangement among its co-obligors and b) any additional amount the reporting entity expects to pay on behalf of its co-obligors.  ASU 2013-04 also requires an entity to disclose the nature and amount of the obligation as well as other information about those obligations.  ASU 2013-04 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2013 and will be applied retrospectively to all prior periods presented for those obligations resulting from joint and several liability arrangements that exist at the beginning of an entity's fiscal year of adoption.  The Company will adopt this pronouncement in the first quarter of 2014 and does not expect its adoption to have a material effect on its financial position or results of operations.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;padding-left:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;padding-left:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;In February 2013, the FASB issued ASU No. 2013-02, &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;font-style:italic;"&gt;Comprehensive Income&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; (&amp;#8220;ASU 2013-02&amp;#8221;), which is intended to improve the reporting of reclassifications out of accumulated other comprehensive income.  ASU 2013-02 does not change the current requirements for reporting net income or other comprehensive income in financial statements.  However, ASU 2013-02 requires an entity to provide information about the amounts reclassified out of accumulated other comprehensive income by component.  In addition, an entity is required to present, either on the face of the statement where net income is presented or in the notes, significant amounts reclassified out of accumulated other comprehensive income by the respective line items of net income but only if the amount reclassified is required under U.S. GAAP to be reclassified to net income in its entirety in the same reporting period.  For other amounts that are not required under U.S. GAAP to be reclassified in their entirety to net income, an entity is required to cross-reference to other disclosures required under U.S. GAAP that provide additional detail about those amounts.  The Company adopted ASU 2013-02 in the first quarter of 2013.  The adoption of ASU 2013-02 had no effect on the Company's financial position or results of operations, but did impact the way the Company presented comprehensive income.&lt;/font&gt;&lt;/div&gt;&lt;/div&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for the general note to the financial statements for the reporting entity which may include, descriptions of the basis of presentation, business description, significant accounting policies, consolidations, reclassifications, new pronouncements not yet adopted and changes in accounting principles.</ElementDefenition><ElementReferences>No definition available.</ElementReferences><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Basis of Presentation</Label></Row></Rows><Footnotes /><IsEquityReport>false</IsEquityReport><ReportName>Basis of Presentation</ReportName><MonetaryRoundingLevel>UnKnown</MonetaryRoundingLevel><SharesRoundingLevel>UnKnown</SharesRoundingLevel><PerShareRoundingLevel>UnKnown</PerShareRoundingLevel><ExchangeRateRoundingLevel>UnKnown</ExchangeRateRoundingLevel><HasCustomUnits>true</HasCustomUnits><IsEmbedReport>false</IsEmbedReport><IsMultiCurrency>false</IsMultiCurrency><ReportType>Sheet</ReportType><RoleURI>http://www.nortek-inc.com/role/BasisOfPresentation</RoleURI><NumberOfCols>1</NumberOfCols><NumberOfRows>2</NumberOfRows></InstanceReport>
