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                                                                     EXHIBIT 4.5


                             SUPPLEMENTAL INDENTURE

                  This Supplemental Indenture (this "SUPPLEMENTAL INDENTURE"),
dated as of the 31st day of December 2002, among Interface Fabrics Group
Marketing, Inc., a Nevada corporation and Strategic Flooring Services, Inc., a
Georgia corporation (each a "GUARANTEEING SUBSIDIARY"), both of which are
Subsidiaries of Interface, Inc. (or its permitted successor), a Georgia
corporation (the "COMPANY"), the Company, the Guarantors (as defined in the
Indenture referred to herein) and Wachovia Bank, National Association (formerly
known as First Union National Bank), as trustee under the Indenture referred to
below (the "TRUSTEE").

                                  WITNESSETH

                  WHEREAS, the Company and the Guarantors party thereto
heretofore executed and delivered to the Trustee an indenture (the
"INDENTURE"), dated as of January 17, 2002 providing for the issuance of
10.375% Senior Notes due 2010 (the "NOTES");

                  WHEREAS, the Indenture provides that under certain
circumstances a Material U.S. Subsidiary shall, and other Subsidiaries may,
execute and deliver to the Trustee a supplemental indenture pursuant to which
the Guaranteeing Subsidiary shall unconditionally guarantee all of the
Company's Obligations under the Notes and the Indenture on the terms and
conditions set forth herein (the "GUARANTEE"); and

                  WHEREAS, pursuant to Section 9.01 of the Indenture, the
Trustee is authorized to execute and deliver this Supplemental Indenture.

                  NOW THEREFORE, in consideration of the foregoing and for
other good and valuable consideration, the receipt of which is hereby
acknowledged, each Guaranteeing Subsidiary and the Trustee mutually covenant
and agree for the equal and ratable benefit of the Holders of the Notes as
follows:

Section 1.        Capitalized Terms.

         Capitalized terms used herein without definition shall have the
meanings assigned to them in the Indenture.

Section 2.        Agreement to Guarantee.

         Each Guaranteeing Subsidiary signatory hereto hereby agrees as
follows:

                  (a)      Along with all other Guarantors, to jointly and
severally Guarantee to each Holder of a Note authenticated and delivered by the
Trustee and to the Trustee and its successors


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and assigns, irrespective of the validity and enforceability of the Indenture,
the Notes or the obligations of the Company hereunder or thereunder, that:

                           (i)      the principal of, premium, if any, and
                  interest (including any Special Interest), on the Notes will
                  be promptly paid in full when due, whether at maturity, by
                  acceleration, redemption or otherwise, and interest on the
                  overdue principal, premium, if any, of and interest on the
                  Notes, if any, if lawful, and all other obligations of the
                  Company to the Holders or the Trustee hereunder or thereunder
                  will be promptly paid in full or performed, all in accordance
                  with the terms hereof and thereof; and

                           (ii)     in case of any extension of time of payment
                  or renewal of any Notes or any of such other obligations,
                  that same will be promptly paid in full when due or performed
                  in accordance with the terms of the extension or renewal,
                  whether at stated maturity, by acceleration or otherwise.
                  Failing payment when due of any amount so guaranteed or any
                  performance so guaranteed for whatever reason, the Guarantors
                  shall be jointly and severally obligated to pay the same
                  immediately.

                  (b)      The obligations hereunder shall be unconditional,
irrespective of the validity, regularity or enforceability of the Notes or the
Indenture, the absence of any action to enforce the same, any waiver or consent
by any Holder of the Notes with respect to any provisions hereof or thereof,
the recovery of any judgment against the Company, any action to enforce the
same or any other circumstance which might otherwise constitute a legal or
equitable discharge or defense of a guarantor.

                  (c)      The following is hereby waived: diligence,
presentment, demand of payment, filing of claims with a court in the event of
insolvency or bankruptcy of the Company, any right to require a proceeding
first against the Company, protest, notice and all demands whatsoever.

                  (d)      This Guarantee shall not be discharged except by
complete performance of the obligations contained in the Notes and the
Indenture.

                  (e)      If any Holder or the Trustee is required by any
court or otherwise to return to the Company, the Guarantors, or any custodian,
Trustee, liquidator or other similar official acting in relation to either the
Company or the Guarantors, any amount paid by either to the Trustee or such
Holder, this Guarantee, to the extent theretofore discharged, shall be
reinstated in full force and effect.

                  (f)      None of the Guaranteeing Subsidiaries signatory
hereto shall not be entitled to any right of subrogation in relation to the
Holders in respect of any obligations guaranteed hereby until payment in full
of all obligations guaranteed hereby.

                  (g)      As between the Guarantors, including each Guarantor
Subsidiary signatory hereto, on the one hand, and the Holders and the Trustee,
on the other hand, (x) the maturity of


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the obligations guaranteed hereby may be accelerated as provided in Article 6
of the Indenture for the purposes of this Guarantee, notwithstanding any stay,
injunction or other prohibition preventing such acceleration in respect of the
obligations guaranteed hereby, and (y) in the event of any declaration of
acceleration of such obligations as provided in Article 6 of the Indenture,
such obligations (whether or not due and payable) shall forthwith become due
and payable by each Guaranteeing Subsidiary for the purpose of this Guarantee.

                  (h)      Each Guaranteeing Subsidiary shall have the right to
seek contribution from any non-paying Guarantor (including any other
Guaranteeing Subsidiary) so long as the exercise of such right does not impair
the rights of the Holders under the Guarantee.

                  (i)      Pursuant to Section 10.02 of the Indenture, after
giving effect to any maximum amount and any other contingent and fixed
liabilities that are relevant under any applicable Bankruptcy or fraudulent
conveyance laws, and after giving effect to any collections from the Company
and any of the other Guarantors, the rights of each Guaranteeing Subsidiary
signatory hereto to receive contribution from or payments made by or on behalf
of any other Guarantor (including any other Guaranteeing Subsidiary) in respect
of the obligations of such other Guarantor under Article 10 of the Indenture
shall result in the obligations of each Guaranteeing Subsidiary under its
Guarantee not constituting a fraudulent transfer or conveyance.

3.       Execution and Delivery.

         Each Guaranteeing Subsidiary agrees that the Guarantees shall remain
in full force and effect notwithstanding any failure to endorse on each Note a
notation of such Guarantee.

4.       Guarantors May Consolidate, Etc. on Certain Terms.

                  (a)      No Guarantor may merge or consolidate with or into
(whether or not such Guarantor is the surviving Person), sell, assign, convey,
transfer, lease or otherwise dispose of all or substantially all of its
properties and assets, as an entirety, to any Person or Persons, other than the
Company or another Guarantor, unless:

                           (i)      immediately after giving effect to that
                  transaction, no Default or Event of Default exists; and

                           (ii)     either:

                                    (A)      the Person acquiring the property
                           in any such sale or disposition or the Person formed
                           by or surviving any such consolidation or merger
                           assumes all the obligations of that Guarantor under
                           this Indenture, its Guarantee and the Registration
                           Rights Agreement pursuant to a supplemental
                           indenture satisfactory to the Trustee, or


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                                    (B)      the Guarantor is released pursuant
                           to Section 11.07 and such sale or other disposition
                           complies with Section 4.12 of the Indenture,
                           including the application of the Excess Proceeds
                           therefrom.

                  (b)      In case of any such consolidation, merger, sale or
conveyance and upon the assumption by the successor corporation, by
supplemental indenture, executed and delivered to the Trustee and satisfactory
in form to the Trustee, of the Guarantee endorsed upon the Notes and the due
and punctual performance of all of the covenants and conditions of this
Indenture to be performed by the Guarantor, such successor corporation shall
succeed to and be substituted for the Guarantor with the same effect as if it
had been named herein as a Guarantor. Such successor corporation thereupon may
cause to be signed any or all of the Guarantees to be endorsed upon all of the
Notes issuable hereunder which theretofore shall not have been signed by the
Company and delivered to the Trustee. All the Guarantees so issued shall in all
respects have the same legal rank and benefit under the Indenture as the
Guarantees theretofore and thereafter issued in accordance with the terms of
this Indenture as though all of such Guarantees had been issued at the date of
the execution hereof.

                  (c)      Except as set forth in Article 4 and Article 5 of
the Indenture, and notwithstanding clauses (a) and (b) above, nothing contained
in this Indenture or in any of the Notes shall prevent any consolidation or
merger of a Guarantor with or into the Company or another Guarantor, or shall
prevent any sale or conveyance of the property of a Guarantor as an entirety or
substantially as an entirety to the Company or another Guarantor.

5.       Release of a Guarantor.

                  (a)      Upon the sale or disposition of all of the Capital
Stock of a Guarantor by the Company or a Subsidiary of the Company, or upon the
consolidation or merger of a Guarantor with or into any Person (in each case,
other than to, with or into, as the case may be, the Company or an Affiliate of
the Company), such Guarantor shall be deemed automatically and unconditionally
released and discharged from all obligations under Article 11 of the Indenture
without any further action required on the part of the Trustee or any Holder;
provided, however, that each such Guarantor is sold or disposed of in a
transaction which does not violate Section 4.12 and Section 11.06 of the
Indenture;

                  (b)      The Trustee shall deliver an appropriate instrument
evidencing the release of a Guarantor upon receipt of a request of the Company
accompanied by an Officers' Certificate certifying as to the compliance with
Section 11.06 of the Indenture. Any Guarantor not so released or the entity
surviving such Guarantor, as applicable, will remain or be liable under its
Guarantee as provided in Article 11 of the Indenture.

                  The Trustee shall execute any documents reasonably requested
by the Company or a Guarantor in order to evidence the release of such
Guarantor from its obligations under its Guarantee endorsed on the Securities
and under Article 11 of the Indenture.


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6.       No Recourse Against Others.

         No past, present or future director, officer, employee, incorporator,
stockholder or agent of the Guaranteeing Subsidiary, as such, shall have any
liability for any obligations of the Company or any Guaranteeing Subsidiary
under the Notes, any Guarantees, the Indenture or this Supplemental Indenture
or for any claim based on, in respect of, or by reason of, such obligations or
their creation. Each Holder of the Notes by accepting a Note waives and
releases all such liability. The waiver and release are part of the
consideration for issuance of the Notes. Such waiver may not be effective to
waive liabilities under the federal securities laws and it is the view of the
SEC that such a waiver is against public policy.

7.       Governing Law.

         NEW YORK LAW TO GOVERN. THE INTERNAL LAW OF THE STATE OF NEW YORK
SHALL GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENTAL INDENTURE BUT WITHOUT
GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT
THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

8.       Counterparts.

         The parties may sign any number of copies of this Supplemental
Indenture. Each signed copy shall be an original, but all of them together
represent the same agreement.

9.       Effect of Headings.

         The Section headings herein are for convenience only and shall not
affect the construction hereof.

10.      The Trustee.

         The Trustee shall not be responsible in any manner whatsoever for or
in respect of the validity or sufficiency of this Supplemental Indenture or for
or in respect of the recitals contained herein, all of which recitals are made
solely by each Guarantor signatory thereto and the Company.


                         [signatures on following page]


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                  IN WITNESS WHEREOF, the parties hereto have caused this
Supplemental Indenture to be duly executed, and their respective corporate
seals to be hereunto affixed and attested, all as of the day and year first
above written.


                                    GUARANTEEING SUBSIDIARIES:


                                    Interface Fabrics Group Marketing, Inc., as
                                    a Guarantor


                                    By: /s/ Patrick C. Lynch
                                       ----------------------------------------
                                       Patrick C. Lynch, Vice President


                                    Strategic Flooring Services, Inc., as a
                                    Guarantor


                                    By: /s/ Kevin C. Gallagher
                                       ----------------------------------------
                                       Kevin C. Gallagher, Vice President


                                    TRUSTEE:


                                    Wachovia Bank, National Association


                                    By: /s/ Eric J. Knoll
                                       ----------------------------------------
                                       Name: Eric J. Knoll
                                       Title:  Assistant Vice President


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