More Shares Announced in Armstrong Secondary Public Offering

Armstrong World Industries, Inc. announced the pricing of an underwritten secondary public offering of 12,057,382 common shares of the company held by The Armstrong World Industries, Inc. Asbestos Personal Injury Settlement Trust (the “Trust”) and Armor TPG Holdings, L.P. (together with the Trust, the “Selling Shareholders”) at a price to the public of $51.75 per share. The offering was upsized from the previously announced offering of 10,057,382 shares. The shares are being sold on a pro rata basis by the Selling Shareholders in accordance with their respective ownership interests. The company will not sell any shares in the offering and will not receive any proceeds from the offering.

Deutsche Bank Securities is acting as the sole underwriter for the offering, which is expected to close on or about September 13, 2013, subject to customary closing conditions.

In addition, subject to the completion of the underwritten offering, the company has agreed to purchase from the underwriter 5,057,382 of the 12,057,382 common shares that are the subject of the underwritten offering at a price per share equal to the price paid by the underwriter to the Selling Shareholders in the underwritten offering. The repurchased shares will be held in treasury. The company expects to fund the share repurchase with cash on its balance sheet and borrowings under its credit facility and trade receivables securitization. Each of the closing of the share repurchase and the closing of the underwritten offering is conditioned on the other.

As a result of the underwritten offering, the Selling Shareholders will own less than 50% of the total voting power of the company’s common shares.

Barclays Capital Inc. acted as capital markets advisor to the special committee of the board of directors of the Company in connection with the share repurchase and the underwritten offering. Houlihan Lokey Financial Advisors, Inc. acted as financial advisor to the special committee in connection with the share repurchase. Perella Weinberg Partners acted as independent financial and capital markets advisor to the Trust in connection with both the share repurchase and the underwritten offering.

The shares will be offered pursuant to the company’s automatically effective registration statement (and prospectus) on Form S-3 previously filed with the U.S. Securities and Exchange Commission (the “SEC”). Alternatively, a copy of the prospectus supplement relating to the offering may be obtained by contacting: Deutsche Bank Securities Inc., Attn.: Prospectus Group, 60 Wall Street, New York, NY 10005-2836, Tel: (800) 503-4611, Email: prospectus.cpdg@db.com.