Beacon Roofing Supply, Inc.
POWER OF ATTORNEY
Section 16 Filers (Directors and Officers)


Know all by these presents, that the undersigned hereby
constitutes and appoints Ross D. Cooper, signing singly,
the undersigned's true and lawful attorney-in-fact to:

(1)execute for and on behalf of the undersigned, in
the undersigned's capacity as an
officer and/or director of Beacon Roofing Supply, Inc.
the "Company"), Forms 3, 4 and 5 in accordance with
Section 16(a) of the Securities Exchange Act of
1934 and the rules thereunder;

(2)do and perform any and all acts for and on behalf of the
undersigned which may be necessary or desirable to complete
and execute any such Form 3, 4, or 5, complete and
execute any amendment or amendments thereto, and timely
file such form with the United States Securities and Exchange
Commission and any stock  exchange or similar authority; and

(3)take any other action of any type whatsoever in connection
with the foregoing which, in the opinion of such attorney-in-fact,
may be of benefit to, in the best interest of, or legally
required by, the undersigned, it being understood that the
documents executed by such attorney-in-fact on behalf of the
undersigned pursuant to this Power of Attorney shall be in
such form and shall contain such terms and conditions as such
attorney-in-fact may approve in such attorney-in-fact's discretion.

The undersigned hereby grants to each such attorney-in-fact full
power and authority to do and perform any and every act and thing
whatsoever requisite, necessary, or proper to be
one in the exercise of any of the rights and powers herein
granted, as fully to all intents and purposes as the undersigned
might or could do if personally present, with full power of
substitution or revocation, hereby ratifying and confirming
all that such attorney-in-fact, or such attorney-in-fact's substitute
or substitutes, shall lawfully do or cause to be done by virtue of
this power of attorney and the rights and powers herein granted.
The undersigned acknowledges that the foregoing attorneys-in-fact,
in serving in such capacity at the request of the undersigned,
are not assuming,nor is the Company assuming, any of the
undersigned's responsibilities to comply with Section 16 of
the Securities Exchange Act of 1934. This Power of Attorney
shall remain in full force and effect
until the undersigned is no longer required to file Forms 3, 4,
and 5 with respect to the undersigned's holdings of and
transactions in securities issued by the Company, unless earlier
revoked by the undersigned in a signed writing delivered to the
foregoing attorneys-in-fact.

IN WITNESS WHEREOF, the undersigned has caused this Power
of Attorney to be executed as of this 30th day of October, 2018.

/s/ Barbara G.Fast

Barbara G.Fast