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                           TENDER OF ALL OUTSTANDING

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<S>                                            <C> <C>
           7 1/4% SENIOR NOTES DUE             AND            SENIOR FLOATING RATE NOTES DUE
               OCTOBER 1, 2012                                        OCTOBER 1, 2010
                      OF                                                    OF
          AINSWORTH LUMBER CO. LTD.                              AINSWORTH LUMBER CO. LTD.
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To Our Clients:

     We are enclosing herewith a prospectus, dated           ,      (the
"Prospectus") of Ainsworth Lumber Co. Ltd. ("Ainsworth"), and a related letter
of transmittal (the "Letter of Transmittal", which, together with the
Prospectus, constitutes the "Exchange Offer") relating to the offer by
Ainsworth, to exchange (a) its 7 1/4% Senior Notes due October 1, 2012 (the "New
Fixed Rate Notes"), which have been registered under the Securities Act of 1933,
as amended (the "Securities Act") for a like principal amount of its issued and
outstanding 7 1/4% Senior Notes due October 1, 2012 (the "Original Fixed Rate
Notes") and (b) its Senior Floating Rate Notes due October 1, 2010 (the "New
Floating Rate Notes", and, together with the New Fixed Rate Notes, the "Exchange
Notes") for a like principal amount of its issued and outstanding Senior
Floating Rate Notes due October 1, 2010 (the "Original Floating Rate Notes",
and, together with the Original Fixed Rate Notes, the "Original Notes"), in each
case upon the terms and subject to the conditions set forth in the Exchange
Offer.

     PLEASE NOTE THAT THE EXCHANGE OFFER WILL EXPIRE AT 5:00 P.M., NEW YORK CITY
TIME, ON           ,
UNLESS EXTENDED BY AINSWORTH IN ITS SOLE DISCRETION.

     THE EXCHANGE OFFER IS NOT CONDITIONAL UPON ANY MINIMUM NUMBER OF ORIGINAL
NOTES BEING TENDERED.

     We are the holder of record of Original Notes held by us for your account.
A tender of such Original Notes can be made only by us as the record holder and
pursuant to your instructions. The Letter of Transmittal is furnished to you for
your information only and cannot be used by you to tender Original Notes held by
us for your account.

     We request instructions as to whether you wish to tender any or all of the
Original Notes held by us for your account pursuant to the terms and conditions
of the Exchange Offer. Please so instruct us by completing, executing and
returning to us the enclosed instruction to Registered Holder from Beneficial
Holder enclosed herewith. We also request that you confirm with such instruction
form that we may on your behalf make the representations contained in the Letter
of Transmittal.

     Pursuant to the Letter of Transmittal, each holder of Original Notes will
represent to Ainsworth (i) the Exchange Notes acquired in the Exchange Offer are
being obtained in the ordinary course of business of the person receiving such
Exchange Notes, whether or not such person is such holder, (ii) neither the
holder of the Original Notes nor any such other person has an arrangement or
understanding with any person to participate in the distribution of such
Exchange Notes, (iii) if the holder is not a broker-dealer or is a broker-dealer
but will not receive Exchange Notes for its own account in exchange for Original
Notes, neither the holder nor any such other person is engaged in or intends to
participate in a distribution of the Exchange Notes and (iv) neither the holder
nor any such other person is an "affiliate" of Ainsworth within the meaning of
Rule 405 under the Securities Act or, if such holder is an "affiliate", that
such holder will comply with the registration and prospectus delivery
requirements of the Securities Act to the extent applicable. If the tendering
holder is a broker-dealer (whether or not it is also an "affiliate") that will
receive Exchange Notes for its own account in exchange for Original Notes, we
will represent on behalf of such broker-dealer that the Original Notes to be
exchanged for the Exchange Notes were acquired by it as a result of
market-making activities or other trading activities, and acknowledge on behalf
of such broker-dealer that it will deliver a prospectus meeting the requirements
of the Securities Act in connection with any resale of such Exchange Notes. By
acknowledging that it will deliver and by delivering a prospectus meeting the
requirements of the Securities Act in connection with any resale of such
Exchange Notes, a broker-dealer will not be deemed to admit that it is an
"underwriter" within the meaning of the Securities Act.

                                         Very truly yours.