<PAGE>
                                                                    EXHIBIT 4.15

                      JOINT AND SEVERAL INDEMNITY AGREEMENT

            AGREEMENT dated as of September___, 1998 by and between James Hardie
N.V., a corporation formed under the laws of The Netherlands (the
"Corporation"), and James Hardie (USA) Inc., a corporation formed under the laws
of the State of Nevada ("Inc" and together with the Corporation, the
"Indemnitors") on the one hand, and _______ (the "Indemnitee"), on the other.

                                    RECITALS

            The Indemnitee is, or is willing to become, a director and/or
officer of the Corporation, Inc and/or an Affiliate Indemnitee (as hereinafter
defined). Each of the Indemnitors and the Indemnitee recognize the increased
risk of litigation and other claims being asserted against directors and
officers of public companies in today's environment.

            The Articles of Association of the Corporation and the Articles of
Incorporation and Bylaws of Inc (collectively, the "Charter Documents") permit
the Indemnitors to indemnify their respective directors and officers as
currently provided therein. The Charter Documents permit the Indemnitors to
purchase and maintain insurance or to furnish similar protection or make other
arrangements (any such insurance, protection or arrangement, an "Indemnification
Arrangement") on behalf of the Indemnitee against personal liability (including,
but not limited to, providing for Advanced Amounts as hereinafter defined)
asserted against him or incurred by or on behalf of him in such capacity as a
director or officer of such Indemnitor or as an Affiliate Indemnitee, or arising
out of his status as such, whether or not such Indemnitor would have the power
to indemnify him against such liability under the provisions of this Agreement
or under applicable law, including Title 7 of the Nevada Revised Statutes
(hereinafter the Nevada General Corporation Law or the "NGCL"). as it may then
be in effect.

            In part to provide the Indemnitee with specific contractual
assurance of substantial protection against personal liability (regardless of,
among other things, any amendment to or revocation of the aforementioned
provisions of any of the Indemnitor's Charter Documents or any change in the
composition of such Indemnitor's Board of Directors or control of such
Indemnitor), each of the Indemnitors desires to enter into this Agreement. The
NGCL expressly recognizes that the indemnification provisions of the NGCL are
not exclusive of any other rights to which a person seeking indemnification may
be entitled under the Charter Documents, or an agreement providing for
indemnification, or a resolution of stockholders or directors, or otherwise, and
the Charter Documents of the Indemnitors expressly recognize that the
indemnification provisions of the Charter Documents shall not be deemed
exclusive of, and shall not affect, any other rights to which a person seeking
indemnification may be entitled under any agreement, and this Agreement is being
entered into pursuant to the Charter Documents, as permitted by applicable law,
and has been authorized by the stockholders of the Indemnitors.

            In order to induce the Indemnitee to serve as a director and/or
officer of the Corporation and/or Inc and in consideration of the Indemnitee's
so serving, each of the

<PAGE>

Indemnitors desires jointly and severally to hold harmless and indemnify the
Indemnitee and to make arrangements pursuant to which the Indemnitee may be
advanced or reimbursed expenses incurred by the Indemnitee in certain
proceedings, in every case to the fullest extent authorized or permitted by the
NGCL, or any other applicable law, or by any amendment thereof or other
statutory provisions authorizing or permitting such indemnification which are
adopted after the date hereof (but, in the case of any such amendment, only to
the extent that such amendment permits the Indemnitor to provide broader
indemnification rights than the NGCL, or other applicable law, permitted such
Indemnitor to provide prior to such amendment).

            NOW, THEREFORE, in consideration of the foregoing recitals and of
the Indemnitee's willingness to serve the Corporation and/or Inc as a director
and/or officer, the parties agree as follows:

            1. Indemnification. (a) To the fullest extent allowed by law, each
of the Indemnitors, jointly and severally, shall hold harmless and indemnify the
Indemnitee, his executors, administrators or assigns against any and all
expenses, liabilities and losses (including, without limitation, investigation
expenses, expert witnesses' and attorneys' fees and expenses, judgments,
penalties, fines, amounts paid or to be paid in settlement, any interest,
assessments, or other charges imposed thereon and any federal, state, local or
foreign taxes imposed as a result of actual or deemed receipt of any payment
hereunder) actually incurred by the Indemnitee (net of any related insurance
proceeds or other amounts received by the Indemnitee or paid by or on behalf of
an Indemnitor on the Indemnitee's behalf in compensation of such expenses,
liabilities or losses) in connection with any actual or threatened action, suit
or proceeding, whether civil, criminal, administrative or investigative or in
arbitration, to which the Indemnitee is a party or participant or is threatened
to be made a party or participant (a "Proceeding"), as a plaintiff, defendant,
respondent, witness or otherwise, based upon, arising from, relating to or by
reason of the fact that the Indemnitee: (a) is, was, shall be or shall have
been a director and/or officer of an Indemnitor or (b) is or was serving, shall
serve, or shall have served at the request of an Indemnitor as a director,
officer, partner, trustee, fiduciary, employee or agent ("Affiliate Indemnitee")
of another foreign or domestic corporation or non-profit corporation,
cooperative, partnership, joint venture, trust, employee benefit plan, or other
incorporated or unincorporated enterprise (each, a "Company Affiliate"); or
arising from or relating to any action or omission to act taken by the
Indemnitee in any of the foregoing capacities; provided, however, that, except
as provided in Section 9(b) hereof, an Indemnitor shall indemnify the Indemnitee
in connection with a Proceeding initiated by the Indemnitee only if such
proceeding (or part thereof) was authorized by a two-thirds vote of the Board of
Directors of such Indemnitor.

            (b) The Indemnitee shall be presumed to be entitled to such
indemnification under this Agreement upon submission of a written claim pursuant
to Section 4 hereof. Thereafter, the Indemnitors shall have the burden of proof
to overcome the presumption that the Indemnitee is so entitled. Such presumption
shall only be overcome by a judgment or other final adjudication, after all
appeals and all time for appeals has expired ("Final Determination"), which is
adverse to the Indemnitee and which establishes (i) that his acts were committed
in bad faith, or were the result of active and deliberate dishonesty or

                                       2
<PAGE>

willful fraud or illegality, and were material to the cause of action so
adjudicated or (ii) that the Indemnitee in fact personally gained a financial
profit or other advantage to which he was not legally entitled. If the
Indemnitee is not wholly successful in any Proceeding but is successful on the
merits or otherwise as to one or more but less than all claims, issues or
matters in such Proceeding the Indemnitors agree, jointly and severally, to
indemnify the Indemnitee to the maximum extent permitted by law against all
losses and expenses incurred by the Indemnitee in connection with each
successfully resolved claim, issue or matter. Neither the failure of any of the
Indemnitors (including their' respective Boards of Directors, legal counsel or
stockholders) to have made a determination prior to the commencement of such
Proceeding that indemnification of the Indemnitee is proper in the circumstances
because such person has met the applicable standard of conduct, nor an actual
determination by such Indemnitor (including its Board of Directors, its legal
counsel or its stockholders) that the Indemnitee has not met the applicable
standard of conduct, shall be a defense to the action or create a presumption
that the Indemnitee has not met the applicable standard of conduct. The
purchase, establishment or maintenance of any Indemnification Arrangement shall
not in any way diminish, restrict, limit or adversely affect the rights and
obligations of any of the Indemnitors or of the Indemnitee under this Agreement,
except as expressly provided herein, and the execution and delivery of this
Agreement by the Indemnitors and the Indemnitee shall not in any way diminish,
restrict, limit or adversely affect the Indemnitee's right to indemnification
from the Indemnitors or any other party or parties under any other
Indemnification Arrangement, the Charter Documents of any of the Indemnitors, or
applicable law.

            2, Period of Limitations. No legal action shall be brought and no
cause of action shall be asserted by or on behalf of an Indemnitor or any
affiliate of an Indemnitor against the Indemnitee, Indemnitee's spouse, heirs,
executors, or personal or legal representatives after the expiration of two
years from the date of accrual of such cause of action, or such longer period as
may be required by applicable law under the circumstances. Any claim or cause of
action of the Indemnitor or its affiliate shall be extinguished and deemed
released unless asserted by the timely filing of a legal action within such
period; provided, however, that if any shorter period of limitations is
otherwise applicable to any such cause of action the shorter period shall
govern.

            3. Insurance. Subject only to the provisions of this Section 3, as
long as the Indemnitee shall continue to serve as a director and/or officer of
an Indemnitor (or shall continue at the request of an Indemnitor to serve as an
Affiliate Indemnitee) and, thereafter, as long as the Indemnitee shall be
subject to any possible Proceeding by reason of the fact that the Indemnitee was
a director and/or officer of an Indemnitor (or served in any of said other
capacities), at least one of the Indemnitors shall use its best efforts to
purchase and maintain in effect for the benefit of the Indemnitee one or more
valid, binding and enforceable policies of directors' and officers' liability
insurance (or maintain an appropriate self-insurance program) providing adequate
liability coverage for the Indemnitee's acts as a director and/or officer of an
Indemnitor or as an Affiliate Indemnitee ("D&O Insurance"). The Indemnitors
shall promptly notify the Indemnitee of any lapse, amendment or failure to renew
said policy or policies or any provision thereof relating to the extent or
nature of coverage provided thereunder. In the event the Indemnitors do not
purchase or maintain in effect said policy or policies of D&O Insurance pursuant
to the provisions of this Section 3,

                                       3
<PAGE>

the Indemnitors shall, in addition to and not in limitation of the other rights
granted the Indemnitee under this Agreement, hold harmless and indemnify the
Indemnitee to the full extent of coverage which would otherwise have been
provided for the benefit of the Indemnitee pursuant to the D&O Insurance.

            4. Claims for Payments. The Indemnitee shall have the right to
receive from the Indemnitors on demand or, at his option, to have any of the
Indemnitors pay promptly on his behalf, in advance of a Final Determination of a
Proceeding, all amounts payable by the Indemnitors pursuant to the terms of this
Agreement as corresponding amounts are expended or incurred by the Indemnitee in
connection with any Proceeding or otherwise (such amounts so expended or
incurred being referred to as "Advanced Amounts"). In making any claim for
payment by the Indemnitors of any amount, including any Advanced Amount,
pursuant to this Agreement, the Indemnitee shall submit to the Indemnitors a
written request for payment (a "Claim") which includes a schedule setting forth
in reasonable detail the dollar amount expended (or incurred or expected to be
expended or incurred). Each item on such schedule shall be supported by the
bill, agreement, or other documentation relating thereto, a copy of which shall
be appended to the schedule as an exhibit.

            Where the Indemnitee is requesting Advanced Amounts, the Indemnitee
must also provide an undertaking to repay such Advanced Amounts if a Final
Determination is made that the Indemnitee is not entitled to indemnification
hereunder.

            5. Section 16(b) Liability. No Indemnitor shall be liable under this
Agreement to make any payment in connection with any claim made against the
Indemnitee for an accounting of profits made from the purchase or sale by the
Indemnitee of securities of an Indemnitor within the meaning of Section 16(b) of
the Securities Exchange Act of 1934, and amendments thereto, or similar
provisions of any state statutory law or common law.

            6. Continuation of Indemnity. All agreements and obligations of the
Indemnitors contained herein shall continue during the period the Indemnitee is
a director and/or officer of an Indemnitor (or is serving at the request of an
Indemnitor as an Affiliate Indemnitee) and shall continue thereafter so long as
the Indemnitee shall be subject to any possible Proceeding by reason of the fact
that the Indemnitee was a director or officer of an Indemnitor or served as such
an Affiliate Indemnitee.

            7. Successors: Binding Agreement. This Agreement shall be binding
on, and shall inure to the benefit of and be enforceable by, each of the
Indemnitor's successors and assigns and by the Indemnitee's personal or legal
representatives, executors, administrators, successors, heirs, distributees,
divisees and legatees. Each Indemnitor shall require any successor or assignee
(whether direct or indirect, by purchase, merger, consolidation or otherwise) to
all or substantially all of the business and/or assets of such Indemnitor
expressly to assume and agree in writing to perform this Agreement in the same
manner and to the same extent that such Indemnitor would be required to perform
if no such succession or assignment had taken place.

                                       4
<PAGE>

            8. Notification and Defense of Claim. Promptly after receipt by the
Indemnitee of notice of the commencement of any Proceeding, the Indemnitee
shall, if a claim in respect thereof is to be made against an Indemnitor under
this Agreement, notify such Indemnitor of the commencement thereof, but the
failure to so notify such Indemnitor will not relieve the Indemnitors from any
liability which it may have to the Indemnitee (except to the extent that the
Indemnitors are prejudiced by such failure). With respect to any such
Proceeding:

            (i) Each Indemnitor shall be entitled to participate therein at its
      own expense;

            (ii) Except with prior written consent of the Indemnitee, the
      Indemnitors shall not be entitled to assume the defense of any Proceeding;

            (iii) No Indemnitor shall settle any Proceeding in any manner which
      would impose any penalty or limitation on the Indemnitee without the
      Indemnitee's prior written consent (not to be unreasonably withheld or
      delayed); and

            (iv) The Indemnitee shall not settle any Proceeding without the
      Indemnitors' prior written consent (not to be unreasonably withheld or
      delayed).

            9. Enforcement. (a) Each Indemnitor has entered into this Agreement
and assumed the obligations imposed on such Indemnitor hereby in order to induce
the Indemnitee to act as a director and/or officer of the Corporation and/or Inc
or as an Affiliate Indemnitee and acknowledges that the Indemnitee is relying
upon this Agreement in agreeing to serve or continuing in such capacity.

            (b) All expenses incurred by the Indemnitee in connection with the
preparation and submission of the Indemnitee's request for indemnification
hereunder shall be borne, jointly and severally, by the Indemnitors. In the
event the Indemnitee has requested payment of any amount under this Agreement or
under the D&O Insurance and has not received payment thereof within thirty (30)
days of such request, the Indemnitee may bring any action to enforce his rights
or such collect moneys due, and, if the Indemnitee is successful in such action,
the Indemnitors shall reimburse the Indemnitee for all of the Indemnitee's fees
and expenses in bringing and pursuing such action. If it is determined that the
Indemnitee is entitled to indemnification for part (but not all) of the
indemnification so requested, or is entitled to part (but not all) of the
amounts claimed under the D&O Insurance, such fees and expenses shall be
reasonably prorated. The Indemnitee shall be entitled to the advancement of such
amounts to the full extent contemplated by Section 4 hereof in connection with
such Proceeding.

            10. Contribution. If the indemnification provided for herein in
respect of any expense, liability or loss incurred by Indemnitee in connection
with any Proceeding is finally determined by a court of competent jurisdiction
to be prohibited by applicable law, then the Indemnitors, in lieu of
indemnifying Indemnitee, shall contribute to the amount paid or payable by
Indemnitee as a result of such expense, liability or loss in such proportion as
is appropriate to reflect (i) the relative benefits received by the Indemnitors
on the one hand

                                       5
<PAGE>

and Indemnitee on the other hand from the events, circumstances, conditions,
happenings, actions or transactions from which such Proceeding arose, (ii) the
relative fault of the Indemnitors (including their affiliates) on the one hand
and of Indemnitee on the other hand in connection with the events, circumstances
and happenings which resulted in such expense, liability or loss (such relative
fault to be determined by reference to, among other things, the parties relative
intent, knowledge, access to information and opportunity to correct or prevent
the events, circumstances and/or happenings resulting in such expense, liability
or loss), and (iii) any other relevant equitable considerations, it being agreed
that it would not be just and equitable if such contribution were determined by
pro rata or other method of allocation which does not take into account the
foregoing equitable considerations.

            11. Separability. If any provision or provisions of this Agreement
shall be held to be invalid, illegal or unenforceable for any reason whatsoever,
(i) the validity, legality and enforceability of the remaining provisions of
this Agreement (including, without limitation, all portions of any sections or
subsections of this Agreement containing any such provision held to be invalid,
illegal or unenforceable, that are not by themselves invalid, illegal or
unenforceable) shall not in any way be affected or unpaired thereby, and (ii) to
the fullest extent possible, the provisions of any section or subsections of
this Agreement containing any such provisions held to be invalid, illegal or
unenforceable shall be construed so as to give effect to the intent of the
parties that the Indemnitors (or any of them) provide protection to the
Indemnitee to the fullest extent enforceable.

            12. Subrogation. In the event of payment under this Agreement, the
Indemnitors shall be subrogated to the extent of such payment to all of the
rights of recovery of Indemnitee, who shall execute all papers required and
shall do everything that may be necessary to secure such rights.

            13. Miscellaneous. No provision of this Agreement may be modified,
waived or discharged unless such modification, waiver or discharge is agreed to
in a writing signed by the Indemnitee and an officer of each of the Indemnitors
designated by the Board of Directors of such Indemnitor. No waiver by either
party at any time of any breach by the other party of, or of compliance with,
any condition or provision of this Agreement to be performed by such other party
shall be deemed a waiver of similar or dissimilar provisions or conditions at
the same time or at any prior or subsequent time. The validity, interpretation,
construction and performance of this Agreement shall be governed by the laws of
the State of Nevada, without giving effect to the principles of conflicts of
laws thereof.

            14. Notices. For the purposes of this Agreement, notices and all
other communications provided for in the Agreement shall be in writing and shall
be deemed to have been duly given when delivered by hand against a receipt
therefor, received by facsimile, or five days after being mailed by United
States registered mail, return receipt requested, postage prepaid, as follows:

            If to the Indemnitee:       ___________________________
                                        c/o James Hardie N.V.
                                        26300 La Alameda, Suite 100

                                       6
<PAGE>

                                        Mission Viejo, CA 92691
                                        Facsimile No.: 949-367-1294

            If to the Corporation:      James Hardie N.V.
                                        c/o De Brauw Blackstone Westbroek
                                        Tripolis 300
                                        Burgerweeshuispad 301
                                        P.O. Box 75084
                                        1070 AB Amsterdam
                                        The Netherlands
                                        Facsimile No.: 31-20-577-1721
                                        Attn: Martin van Olffen

            With a copy to:             Gibson, Dunn & Crutcher
                                        Jamboree Center
                                        4 Park Plaza
                                        Irvine, CA 92714-8557
                                        Facsimile No.: 949-451-4220
                                        Attn: Mark W. Shurtleff

            If to Inc:                  James Hardie (USA) Inc.
                                        26300 La Alameda Suite 250
                                        Mission Viejo, CA 92691
                                        Facsimile No.: 949-367-1294
                                        Attn: Peter Macdonald

            With a copy to:             Gibson, Dunn & Crutcher
                                        Jamboree Center
                                        4 Park Plaza
                                        Irvine, CA 92714-8557
                                        Facsimile No.: 949-451-4220
                                        Attn: Mark W. Shurtleff

or to such other address as either party may have farnished to the other in
writing in accordance herewith, except that notices of change of address shall
be effective only upon receipt.

            15. Counterparts. This Agreement may be executed in one or more
counterparts, each of which shall be deemed to be an original but all of which
together shall constitute one and the same instrument.

            16. Effectiveness. This Agreement shall be effective as of the day
and year first above written, and shall apply to any Proceedings relating to
matters which occurred prior to such date.

                                       7
<PAGE>

            IN WITNESS WHEREOF, the undersigned have caused this Agreement to be
executed as of the day and year first above written.

                                        JAMES HARDIE N.V.

                                        By:     ________________________________
                                                Name: Don E. Cameron
                                                Title: Managing Director

                                        JAMES HARDIE (USA) INC.

                                        By:     ________________________________
                                                Name:
                                                Title:

                                        INDEMNITEE

                                        By:     ________________________________
                                                Name:

                                       8