April 25, 2019

Joseph Nowicki
Chief Financial Officer
BEACON ROOFING SUPPLY INC.
505 Huntmar Park Drive
Suite 300
Herndon, VA 20170

       Re: BEACON ROOFING SUPPLY INC.
           Form 10-K for the fiscal year ended September 30, 2018
           Filed November 20, 2018
           File No. 000-50924

Dear Mr. Nowicki:

       We have limited our review of your filing to the financial statements
and related
disclosures and have the following comments. In some of our comments, we may
ask you to
provide us with information so we may better understand your disclosure.

       Please respond to these comments within ten business days by providing
the requested
information or advise us as soon as possible when you will respond. If you do
not believe our
comments apply to your facts and circumstances, please tell us why in your
response.

       After reviewing your response to these comments, we may have additional
comments.

Form 10-K for the fiscal year ended September 30, 2018

Non-GAAP Financial Measures
Adjusted Net Income (Loss)/Adjusted EPS, page 25

1.    With regard to your reconciliation of Net Income to Adjusted Net Income,
please
      separately present and identify the material components of the
acquisition costs you are
      excluding from your non-GAAP measure. Please also present the tax effect
of these
      adjustments as a separate line item. Refer to Question 102.11 of the
Compliance and
      Disclosure Interpretations on Non-GAAP Financial Measures.


2.    Please explain to us why you present Adjusted EPS after assuming full
conversion of the
      participating Preferred Stock and why you believe that information is
useful to your
      investors.
 Joseph Nowicki
BEACON ROOFING SUPPLY INC.
April 25, 2019
Page 2
3.       You state that the weighted-average share count utilized in the 2018
calculation of
         Adjusted EPS assumes conversion of 7,224,483 weighted-average shares
of participating
         Preferred Stock, which were excluded from the determination of GAAP
net income (loss)
         per share for the period due to their anti-dilutive nature. Therefore,
it appears that
         Adjusted EPS, which includes the effect of anti-dilutive shares,
substitutes individually
         tailored recognition and measurement methods for that of GAAP. See ASC
260-10-45-
         17. Please also refer to and tell us how you considered Question
100.04 of the Division's
         Compliance and Disclosure Interpretations on Non-GAAP Financial
Measures.
       In closing, we remind you that the company and its management are
responsible for the
accuracy and adequacy of their disclosures, notwithstanding any review,
comments, action or
absence of action by the staff.

       You may contact Dale Welcome at 202-551-3865 or Jeanne Baker at
202-551-3691 with
any questions.



                                                             Sincerely,
FirstName LastNameJoseph Nowicki
                                                             Division of
Corporation Finance
Comapany NameBEACON ROOFING SUPPLY INC.
                                                             Office of
Manufacturing and
April 25, 2019 Page 2                                        Construction
FirstName LastName