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                                   AMENDMENT
                                       TO
                 AMENDED AND RESTATED STOCK PURCHASE AGREEMENT
                                      AND
                            DEBT EXCHANGE AGREEMENT
 
    AMENDMENT, dated as of October 15, 1995, between the person or entity whose
name is set forth on the Signature Page hereto (the "Holder") and The Alpine
Group, Inc., a Delaware corporation with offices at 1790 Broadway, New York, New
York 10019 ("Alpine").
 
                                    RECITALS
 
    The Holder and Alpine are parties to an Amended and Restated Stock Purchase
Agreement, and an Amended and Restated Debt Exchange Agreement, each dated as of
October 11, 1994 (as amended to date, collectively the "Agreements"). In
connection with the transactions contemplated by the Agreements, the Holder
received, and is currently the legal and beneficial owner of, the respective
numbers of shares of Alpine 8% Preferred Stock and PolyVision Common Stock set
forth in Exhibit A hereto.
 
    Pursuant to Section 1.06 of the Agreements, the Holder is entitled to
receive certain Reset Consideration from Alpine. The parties wish to provide for
the payment and settlement of all of Alpine's obligations with respect to the
Reset Consideration. Accordingly, the Holder and Alpine wish to amend the
Agreements as provided herein.
 
    THEREFORE, in consideration of the mutual agreements herein contained and
for good and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the parties hereby agree as follows:
 
    1. Definitions. Terms defined in the Agreements and used but not otherwise
defined herein shall have the meanings given to them in the Agreements.
 
    2. Exchange.
 
        a.  In full consideration and satisfaction of Alpine's obligations with
    respect to the Reset Consideration, pursuant to Section 1.06 of the
    Agreements or otherwise, Alpine shall transfer and deliver to the Holder the
    number of shares of Alpine Common Stock and PolyVision Common Stock set
    forth on Exhibit A, and the Holder shall transfer and deliver to Alpine the
    number of shares of Alpine 8% Preferred Stock set forth on Exhibit A. The
    transfers and deliveries contemplated by this Amendment shall take place
    simultaneously with the execution of this Amendment.
 
        b.  Neither certificates nor scrip for fractional shares of Alpine
    Common Stock or PolyVision Common Stock will be issued in connection with
    the transaction contemplated hereby, but in lieu thereof the Holder
    otherwise entitled to a fraction of a share of Alpine Common Stock or
    PolyVision Common Stock as set forth on Exhibit A shall be paid in cash an
    amount equal to such fraction multiplied by (1) $5.75 (in the case of a
    fractional share of Alpine Common Stock) or (2) $3.5625 (in the case of a
    fractional share of PolyVision Common Stock), in each case rounded upward or
    downward to the nearest whole cent.
 
    3. Registration. Alpine confirms that it will effect a registration under
the Securities Act of the Alpine Common Stock transferred and delivered
hereunder in accordance with the provisions of Section 5.02 of the Agreements
and that the provisions of Section 5.01 of the Agreements (relating to
registration of the PolyVision Common Stock) apply to the PolyVision Common
Stock transferred hereunder. The Holder acknowledges and agrees that Alpine will
not be required to effect, and no registration will be effected, with respect to
the Alpine 8% Preferred Stock.
 
    4. Representations.
 
        a.  The Holder represents to Alpine that the Holder is the legal and
    beneficial owner of the respective numbers of shares of Alpine 8% Preferred
    Stock and PolyVision Common Stock set forth on Exhibit A. The Holder repeats
    and reaffirms each of the representations and warranties set forth in
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    Sections 2.01 and 2.02 of the Agreements, modified to apply to the Alpine 8%
    Preferred Stock being transferred and delivered by it hereunder and to the
    PolyVision Common Stock owned by it.
 
        b.  The Holder repeats and reaffirms each of the representations and
    warranties set forth in Sections 2.03 through 2.05 of the Agreements,
    modified to apply to the Alpine Common Stock and PolyVision Common Stock
    being acquired hereunder.
 
        c.  Alpine repeats and reaffirms each of the representations and
    warranties set forth in Sections 3.01 through 3.05 of the Agreements,
    modified to apply to the Alpine 8% Preferred Stock being acquired hereunder.
 
        5.  Other. All other terms and conditions of the Agreements shall remain
    in full force and effect without modification.
 
                            [SIGNATURE PAGE FOLLOWS]
 
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    This Amendment has been duly executed on the date hereinabove set forth.
 
                                          THE ALPINE GROUP, INC.
 
                                          By:
  ------------------------------------------------------------------------------
                                             Name:
                                             Title:
 
                                          The Holder:
 
                                          REFERENCE IS MADE TO THE
                                          COUNTERPART HOLDER'S SIGNATURE PAGE,
                                          EXECUTED BY THE HOLDER AND MADE A PART
                                          HEREOF
 
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