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                                  FORM 51-102F3

                             MATERIAL CHANGE REPORT


ITEM 1    NAME AND ADDRESS OF COMPANY

          Gerdau Ameristeel Corporation
          Hopkins Street South
          Whitby, Ontario
          L1N 5T1

ITEM 2    DATE OF MATERIAL CHANGE

          October 5, 2004

ITEM 3    NEWS RELEASE

          A press release was issued on October 5, 2004 and is attached as
          Schedule "A".

ITEM 4    SUMMARY OF MATERIAL CHANGE

          On October 5, 2004 Gerdau Ameristeel Corporation ("Gerdau Ameristeel")
          filed a preliminary short form base PREP prospectus with the
          securities regulatory authorities in all provinces and territories in
          Canada and a registration statement on Form F-10 with the United
          States Securities and Exchange Commission, in connection with a
          proposed offering in the United States and Canada of 70 million of its
          common shares.

ITEM 5    FULL DESCRIPTION OF MATERIAL CHANGE

          On October 5, 2004 Gerdau Ameristeel filed a preliminary short form
          base PREP prospectus with the securities regulatory authorities in all
          provinces and territories in Canada and a registration statement on
          Form F-10 with the United States Securities and Exchange Commission,
          in connection with a proposed offering (the "Offering") in the United
          States and Canada of 70 million of its common shares (the "Common
          Shares"). Gerdau S.A., which owns approximately 72% of the approximate
          225 million outstanding common shares of Gerdau Ameristeel as of
          September 24, 2004, will purchase 35 million Common Shares in the
          Offering.

          Merrill Lynch, Pierce, Fenner & Smith Incorporated and BMO Nesbitt
          Burns Inc. will act as joint book-running managers for the proposed
          offering in the United States and Canada of the remaining 35 million
          Common Shares. CIBC World Markets Corp., J.P. Morgan Securities Inc.
          and Morgan Stanley & Co. Incorporated will act as underwriters. Gerdau
          Ameristeel has granted the underwriters an overallotment option (the
          "Overallotment Option") to purchase up to an additional 5.25 million
          of its common shares within 30 days following the closing of the
          Offering. Gerdau S.A. has agreed to purchase an equivalent number of
          additional common shares to those purchased under the Overallotment
          Option within two days after any exercise by the underwriters of the
          Overallotment Option.


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ITEM 6    RELIANCE ON SUBSECTION 7.1(2) OR (3) OF NATIONAL INSTRUMENT 51-102

          Not applicable

ITEM 7    OMITTED INFORMATION

          No significant facts remain confidential in, and no information has
          been omitted from, this report.

ITEM 8    EXECUTIVE OFFICER

          For further information, please contact Tom J. Landa, Vice-President,
          Finance, Chief Financial Officer and Secretary at (813) 207-2300.

ITEM 9    DATE OF REPORT

          October 12, 2004

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                                  SCHEDULE "A"

                            [GERDAU AMERISTEEL LOGO]

        GERDAU AMERISTEEL ANNOUNCES FILING OF PRELIMINARY PROSPECTUS FOR
                         OFFERING OF ITS COMMON SHARES


Toronto, ON, October 5, 2004 -- Gerdau Ameristeel Corporation (TSX: GNA.TO)
today announced that it has filed a preliminary short form prospectus with the
securities regulatory authorities in all provinces and territories of Canada,
and a registration statement on Form F-10 with the United States Securities and
Exchange Commission, in connection with a proposed offering in the United States
and Canada of 70 million of its common shares. Gerdau S.A. currently owns
approximately 72% of the approximate 225 million outstanding common shares of
Gerdau Ameristeel as of September 24, 2004, and will purchase 35 million of the
common shares from Gerdau Ameristeel in the proposed offering.

Merrill Lynch, Pierce, Fenner & Smith Incorporated and BMO Nesbitt Burns Inc.
will act as joint book-running managers for a proposed public offering in the
United States and Canada of the remaining 35 million common shares. CIBC World
Markets Corp., J.P. Morgan Securities Inc. and Morgan Stanley & Co. Incorporated
will act as underwriters. Gerdau Ameristeel has also granted to the underwriters
an overallotment option to purchase up to an additional 5.25 million common
shares within 30 days following the closing date. Gerdau S.A. has agreed to
purchase an equivalent number of additional common shares to those purchased
under the overallotment option within two days after any exercise by the
underwriters of the overallotment option. Therefore the maximum aggregate number
of additional common shares issuable to the underwriters and to Gerdau S.A. is
10.5 million. The final terms of this offering will be determined at the time of
pricing.

The purpose of this offering will be to finance Gerdau Ameristeel's previously
announced proposed acquisition of certain assets and working capital of four
long steel product mills and four downstream facilities, which are referred to
as North Star Steel, from Cargill, Incorporated, to fund capital expenditures
and working capital and for general corporate purposes.

A copy of the preliminary prospectus may be obtained by contacting Merrill Lynch
at World Financial Center, 250 Vesey St. New York, NY 10080 or 181 Bay Street,
Suite 400, Toronto, Ontario M6G 2S9, or BMO Nesbitt Burns, 1 First Canadian
Place, 4th Floor, Toronto, Ontario M5X 1H3.

A registration statement relating to the common shares has been filed with the
United States Securities and Exchange Commission but has not yet become
effective. The common shares to be issued under this offering may not be sold,
nor may offers to buy be accepted prior to the time the registration statement
becomes effective. Similarly, these common shares may not be sold in Canada
until a receipt for a final prospectus is obtained. This news release shall not
constitute an offer to sell or the solicitation for an offer to buy, nor shall
there be any sale of the common shares in any state, province, territory or
jurisdiction in which such offer, solicitation or sale


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would be unlawful prior to registration or qualification under the securities
laws of any such state, province, territory or jurisdiction.


ABOUT GERDAU AMERISTEEL

Gerdau Ameristeel is the second largest minimill steel producer in North America
with annual manufacturing capacity of over 6.4 million tons of mill finished
steel products. Through its vertically integrated network of 11 minimills
(including one 50%-owned minimill), 13 scrap recycling facilities and 32
downstream operations, Gerdau Ameristeel primarily serves customers in the
eastern half of North America. The company's products are generally sold to
steel service centers, fabricators, or directly to original equipment
manufacturers for use in a variety of industries, including construction,
automotive, mining and equipment manufacturing. Gerdau Ameristeel's common
shares are traded on the Toronto Stock Exchange under the symbol GNA.TO.

This news release may contain forward-looking information with respect to Gerdau
Ameristeel's operations. Actual results may differ from these forward-looking
statements due to numerous factors, including global competition, steel imports,
market supply and demand for steel, pricing of energy and raw material inputs
and other matters. These and other factors are outlined in Gerdau Ameristeel's
regulatory filings with the Canadian securities regulatory authorities and the
United States Securities and Exchange Commission, including those in Gerdau
Ameristeel's Annual Report for 2003 and its Form 40-F.



FOR MORE INFORMATION PLEASE CONTACT:

Tom J. Landa
Vice President and Chief Financial Officer
Gerdau Ameristeel
(813) 207-2300
tlanda@gerdauameristeel.com