SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   FORM 12b-25

                           NOTIFICATION OF LATE FILING

(Check One):   [  ] Form 10-K   [X] Form 11-K   [  ] Form 20-F   [  ] Form 10-Q
[  ] Form N-SAR

For Period Ended:  September 30, 1999

[  ]  Transition Report on Form 10-K
[  ]  Transition Report on Form 20-F
[  ]  Transition Report on Form 11-K
[  ]  Transition Report on Form 10-Q
[  ]  Transition Report on Form N-SAR

                        For the Transition Period Ended:

  Read attached instruction sheet before preparing form. Please print or type.

    Nothing in this form shall be construed to imply that the Commission has
                   verified any information contained herein.

 If the notification relates to a portion of the filing checked above, identify
                 the item(s) to which the notification relates:


                                     PART I
                             REGISTRANT INFORMATION


                        ARMSTRONG WORLD INDUSTRIES, INC.
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                             Full Name of Registrant


                                 Not Applicable
    ------------------------------------------------------------------------
                           Former Name if Applicable


                              2500 Columbia Avenue
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            Address of Principal Executive Office (Street and Number)

                               Lancaster, PA 17604
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                            City, State and Zip Code


                                    PART II
                            RULES 12b-25(b) AND (c)

     If the subject report could not be filed without unreasonable effort or
expense and the registrant seeks relief pursuant to Rule 12b-25(b), the
following should be completed. (Check box if appropriate.)

[X]  (a) The reasons described in reasonable detail in Part III of this form
     could not be eliminated without unreasonable effort or expense;

[X]  (b) The subject annual report, semi-annual report, transition report on
     Form 10-K, Form 20-F, Form 11-K or Form N-SAR, or portion thereof will be
     filed on or before the 15th calendar day following the prescribed due date;
     or the subject quarterly report or transition report on Form 10-Q, or
     portion thereof will be filed on or before the fifth calendar day following
     the prescribed due date; and

[ ] (c) The accountant's statement or other exhibit required by Rule
     12b-25(c) has been attached if applicable.


                                   PART III
                                   NARRATIVE

     State below in reasonable detail why the Form 10-K, 11-K, 20-F, 10-Q, N-SAR
or the transition report portion thereof could not be filed within the
prescribed time period. (Attach extra sheets if needed.)


     Due to a staff resignation and difficulty in the comparability of data
between the trustee and record keeper, the development of the required
information necessary for the Form 11-K filing of the Retirement Savings and
Stock Ownership Plan of Armstrong World Industries, Inc. could not be made
within the prescribed time period without unreasonable difficulty and expense.


                                    PART IV
                               OTHER INFORMATION

(1)  Name and telephone number of person to contact in regard to this
     notification

                       Stephen F. McNamara   (717)               396-3420
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                      (Name)              (Area Code)       (Telephone Number)

(2)  Have all other periodic reports required under Section 13 or 15(d) of the
     Securities Exchange Act of 1934 or Section 30 of the Investment Company Act
     of 1940 during the preceding 12 months or for such shorter period that the
     registrant was required to file such report(s) been filed? If the answer is
     no, identify report(s).

                                 [X] Yes [ ] No

(3)  Is it anticipated that any significant change in results of operations from
     the corresponding period for the last fiscal year will be reflected by the
     earnings statements to be included in the subject report or portion
     thereof?

                                 [ ] Yes [X] No

         If so: attach an explanation of the anticipated change, both
narratively and quantitatively, and, if appropriate, state the reasons why a
reasonable estimate of the results cannot be made.


                       ARMSTRONG WORLD INDUSTRIES, INC.
            -------------------------------------------------------
                  (Name of Registrant as Specified in Charter)
         Has caused this notification to be signed on its behalf by the
                     undersigned thereunto duly authorized.


Date:  March 27, 2000                    By: /s/ Douglas L. Boles
   ---------------                          ------------------------------------
                                            Douglas L. Boles
                                            Vice-Chairman of the
                                            Retirement Committee