Exhibit 5.1
     
    
                                October 29, 1996
     


Armstrong World Industries, Inc.
313 Liberty Street
Lancaster, Pennsylvania  17603

     Re:  Armstrong World Industries, Inc.
          Registration Statement on Form S-3
          ----------------------------------

Gentlemen:
    
     We have acted as counsel to Armstrong World Industries, Inc. (the
"Company") in connection with the preparation of the Registration Statement on
Form S-3 (together with all exhibits thereto and documents incorporated by
reference therein, the "Registration Statement") (SEC File No. 333-6333)
filed by the Company with the Securities and Exchange Commission (the
"Commission"). The Registration Statement relates to the issuance and sale from
time to time, pursuant to Rule 415 of the General Rules and Regulations of the
Commission promulgated under the Securities Act of 1933, as amended (the
"Securities Act"), of the following securities of the Company with an aggregate
initial public offering price of up to $500,000,000: (i) unsecured debt
securities which may be either senior or subordinated debt securities, in one or
more series (the "Debt Securities"), which in each case are to be issued under
an indenture (the "Indenture" and, collectively, the "Indentures") entered into
between the Company and Mellon Bank, N.A. as trustee thereunder (the "Trustee");
(ii) shares of the Company's common stock, $1.00 par value (the "Common Stock"),
with Preferred Stock Purchase Rights attached to each share of Common Stock (the
"Rights"); and (iii) shares of the Company's Class A Preferred Stock, no par
value (the "Preferred Stock"), in one or more series, which may also be issued
in the form of depositary shares (the "Depositary Shares") evidenced by
depositary receipts (the "Receipts"). The Debt Securities, the Common Stock, the
Preferred Stock and the Depositary Shares are collectively referred to herein as
the "Offered Securities."
     
     This opinion is being delivered in accordance with the requirements of Item
601(b)(5) of Regulation S-K promulgated under the Securities Act.

    
Armstrong World Industries, Inc.
October 29, 1996
Page -2-
     


    
     For the purpose of rendering this opinion, we have examined (i) the
registration statements relating to the Offered Securities (SEC File Nos. 333-
6333 and 33-38837); (ii) the form of Indenture for Senior Debt Securities filed
as Exhibit 4.1 and the form of Indenture for Subordinated Debt Securities filed
as Exhibit 4.2 to the Registration Statement; (iii) the Articles of
Incorporation of the Company, as amended to date (the "Articles of
Incorporation"); (iv) the Bylaws of the Company, as amended to date (the
"Bylaws"); and (v) certain resolutions adopted by the Board of Directors of the
Company (the "Board of Directors") relating to the issuance of the Offered
Securities. We have also examined originals or copies, certified or otherwise
identified to our satisfaction, of such records of the Company and such
agreements, certificates of public officials, certificates of officers or other
representatives of the Company and others and such other documents, certificates
and records as we have deemed necessary or appropriate as a basis for the
opinions set forth herein.
     
     In our examination, we have assumed without independent verification (i)
the legal capacity of all natural persons; (ii) the genuineness of all
signatures; (iii) the authenticity of all documents submitted to us as
originals; (iv) the conformity to original documents of all documents submitted
to us as certified, conformed or photostatic copies and the authenticity of the
originals of such latter documents; and (v) the power and authority of all
persons other than the Company signing such documents to execute, deliver and
perform such documents, and the valid authorization, execution and delivery of
such documents by such other persons.  As to any facts material to the opinions
expressed herein which were not independently established or verified, we have
relied upon oral or written statements and representations of officers or other
representatives of the Company and others.

     In rendering this opinion, we are not expressing an opinion as the laws of
any jurisdiction other than the Commonwealth of Pennsylvania and the federal
laws of the United States of America to the extent referred to specifically
herein, and we assume no responsibility as to the applicability of any other
jurisdictions to the subject matter hereof or to effects of such laws thereon.
The Offered Securities may be issued from time to time on a delayed or
continuous basis, and this opinion is limited to the laws, including applicable
rules and regulations, in effect on the date hereof.  We assume no obligation to
update such opinion.

     Based upon and subject to the foregoing, such examinations of law and such
other matters as we have deemed relevant under the circumstances, we are of the
opinion that, as of the date hereof:



  
Armstrong World Industries, Inc.
October 29, 1996
Page -3-



    
     1.  With respect to any series of Debt Securities (the "Offered Debt
Securities"), when (i) if the Offered Debt Securities are to be sold pursuant to
a firm commitment underwritten offering, the underwriting agreement with respect
to the Offered Debt Securities (the "Debt Underwriting Agreement") has been duly
authorized, executed and delivered by the Company and the other parties thereto;
(ii) if the Offered Debt Securities are to be sold on an agency basis, the
distribution agreement with respect to the Offered Debt Securities (the "Debt
Distribution Agreement") has been duly authorized, executed and delivered by the
Company and the other parties thereto; (iii) the Board of Directors, including
any appropriate committee appointed thereby, and appropriate officers of the
Company have taken all necessary corporate action to approve the issuance and
terms of the Offered Debt Securities and related matters; (iv) the terms of the
Offered Debt Securities and of their issuance and sale have been duly
established in conformity with the Indenture relating thereto so as not to
violate any applicable law, the Articles of Incorporation or Bylaws or result in
a default under or breach of any agreement or instrument binding upon the
Company and so as to comply with any requirement or restriction imposed by any
court or governmental body having jurisdiction over the Company; (v) the
applicable Indenture has been duly executed and delivered by the Company and the
Trustee thereunder; and (vi) the Offered Debt Securities have been duly executed
and authenticated in accordance with the provisions of the applicable Indenture
and duly delivered to the purchasers thereof upon payment of the agreed-upon
consideration therefor, the Offered Debt Securities, when issued and sold in
accordance with the applicable Indenture and the related Debt Underwriting
Agreement or Debt Distribution Agreement, if any, or any other duly authorized,
executed and delivered applicable purchase agreement, will be valid and binding
obligations of the Company, enforceable against the Company in accordance with
their respective terms, except to the extent that enforcement thereof may be
limited by (a) bankruptcy, insolvency, reorganization, fraudulent transfer,
moratorium or other similar laws now or hereafter in effect relating to or
affecting creditors' rights generally, and (b) general principles of equity
(regardless of whether enforceability is considered in a proceeding at law or in
equity).
     
    
     2. With respect to any shares of Common Stock with attached Rights (the
"Offered Common Stock"), when, (i) the underwriting agreement with respect to
the Offered Common Stock (the "Common Stock Underwriting Agreement") has been
duly authorized, executed and delivered by the
     


     
Armstrong World Industries, Inc.
October 29, 1996
Page -4-
    


    
Company and the other parties thereto; (ii) the Board of Directors, including
any appropriate committee appointed thereby, and appropriate officers of the
Company have taken all necessary corporate action to approve the issuance and
terms of issuance of the shares of Offered Common Stock in conformity with the
Articles of Incorporation and the Bylaws, so as not to violate any applicable
law, the Articles of Incorporation or the Bylaws or result in a default under or
breach of any agreement or instrument binding upon the Company and so as to
comply with any requirement or restriction imposed by any court or governmental
body having jurisdiction over the Company; and (iii) certificates representing
the Offered Common Stock are duly executed, countersigned, registered and
delivered upon payment of the agreed-upon consideration therefor, the Offered
Common Stock, when issued and sold in accordance with the related Common Stock
Underwriting Agreement or Common Stock distribution agreement, if any, or any
other duly authorized, executed and delivered applicable purchase agreement,
will be duly authorized and validly issued, and, the shares of Common Stock
will be fully paid and nonassessable, provided that the consideration therefor
is not less than the par value thereof.
     
    
     3. With respect to the shares of any series of Preferred Stock (the
"Offered Preferred Stock"), when, (i) the underwriting agreement with respect to
the shares of the Offered Preferred Stock (the "Preferred Stock Underwriting
Agreement") has been duly authorized, executed and delivered by the Company and
the other parties thereto; (ii) the Board of Directors, including any
appropriate committee appointed thereby, and appropriate officers of the Company
have taken all necessary corporate action to approve the issuance and terms of
the shares of the Offered Preferred Stock and related matters, including the
adoption of a statement of designation for the Offered Preferred Stock in the
form required by applicable law (the "Statement of Designation"); (iii) the
filing of the Statement of Designation with the Department of State of the
Commonwealth of Pennsylvania has duly occurred; (iv) the terms of the Offered
Preferred Stock and of their issuance and sale have been duly established in
conformity with the Articles of Incorporation, the Statement of Designation and
the Bylaws, so as not to violate any applicable law, the Articles of
Incorporation, the Statement of Designation or the Bylaws or result in a default
under or breach of any agreement or instrument binding upon the Company and so
as to comply with any requirement or restriction imposed by any court or
governmental body having jurisdiction over the Company; and (v) certificates
representing the shares of the Offered Preferred Stock are duly executed,
countersigned, registered and delivered upon payment of the agreed-upon
     


     
Armstrong World Industries, Inc.
October 29, 1996
Page -5-
    



consideration therefor, the shares of the Offered Preferred Stock, when issued
and sold in accordance with the related Preferred Stock Underwriting Agreement
or Preferred Stock Distribution agreement, if any, or any other duly authorized,
executed and delivered applicable purchase agreement, will be duly authorized,
validly issued, fully paid and nonassessable, provided that the consideration
therefor is not less than the par value thereof.
    
     4. With respect to Depositary Shares representing fractional interests in
any series of Preferred Stock (the "Offered Depositary Shares"), when, (i) the
Preferred Stock Underwriting Agreement with respect to the Offered Depositary
Shares has been duly authorized, executed and delivered by the Company and the
other parties thereto; (ii) the Board of Directors, including any appropriate
committee appointed thereby, and appropriate officers of the Company have taken
all necessary corporate action to approve the issuance and terms of the Offered
Depositary Shares and related matters, including the adoption of the Statement
of Designation for the related series of Preferred Stock in the form required by
applicable law (the "Underlying Preferred Stock Statement of Designation");
(iii) the filing of the Underlying Preferred Stock Statement of Designation with
the Department of State of the Commonwealth of Pennsylvania has duly occurred;
(iv) a deposit agreement between the Company and an institution appointed by the
Company to act as depositary thereunder (the "Deposit Agreement") has been duly
authorized by the Board of Directors and executed and delivered by the Company;
(v) the institution appointed by the Company to act as depositary under the
Deposit Agreement (the "Depositary") has duly authorized, executed and delivered
the Deposit Agreement; (vi) the terms of the Offered Depositary Shares and of
their issuance and sale have been duly established in conformity with the
Deposit Agreement so as not to violate any applicable law, the Articles of
Incorporation or the Bylaws or result in a default under or breach of any
agreement or instrument binding upon the Company and so as to comply with any
requirement or restriction imposed by any court or governmental body having
jurisdiction over the Company; (vii) the related series of Preferred Stock has
been duly authorized, validly issued and delivered to the Depositary for deposit
in accordance with the laws of the Commonwealth of Pennsylvania; and (viii) the
Receipts evidencing the Depositary Shares are duly issued against the deposit of
the Preferred Stock in accordance with the Deposit Agreement, such Offered
Depositary Shares will be validly issued and the Receipts will entitle the
holders thereof to the rights specified therein and in the Deposit Agreement,
provided that the consideration therefor is not less than the par value of the
Preferred Stock represented by such Offered Depositary Shares.
     


   
Armstrong World Industries, Inc.
October 29, 1996
Page -6-
    


    
     This opinion is rendered to you and for your benefit solely in connection
with the registration of the Offered Securities. This opinion may not be relied
on by you for any other purpose and may not be relied upon by, nor may copies
thereof be provided to, any other person, firm, corporation or entity for any
purposes whatsoever without our prior written consent. We hereby consent to be
named in the Registration Statement and in each of the Prospectuses as attorneys
who passed upon the legality of the Offered Securities and to the filing of a
copy of this opinion as Exhibit 5 to the Registration Statement. Unless the
prior written consent of our firm is obtained, this opinion is not to be quoted
or otherwise referred to in any written report, proxy statement or other
registration statement, nor is it to be filed with or furnished to any other
governmental agency or other person, except as otherwise required by law.
     
                                 Very truly yours,

                                 BUCHANAN INGERSOLL PROFESSIONAL
                                 CORPORATION

    
                                 By:   /s/ Stephen W. Johnson
                                     -------------------------
                                         Stephen W. Johnson