Exhibit 99.1

Owens Corning Reports Second-Quarter 2012 Results

Company Revises 2012 EBIT Expectation on Weaker Roofing Outlook

TOLEDO, Ohio – August 1, 2012 – Owens Corning (NYSE: OC) today reported consolidated net sales of $1.39 billion in the second quarter of 2012, compared with $1.45 billion during the same period last year.

Second-quarter 2012 adjusted earnings, based on the company’s expected full-year effective tax rate of 25 percent, were $66 million, or $0.54 per diluted share, compared with $85 million, or $0.68 per diluted share, during the same period last year. The company reported net earnings of $39 million, or $0.32 per diluted share, compared with net earnings of $78 million, or $0.62 per diluted share, in the second quarter of 2011. (See Tables 1, 2 and 3 for a discussion and reconciliation of these items.)

“Our second-quarter financial performance represents progress over the first quarter, but the rate of improvement is below our expectations, and we no longer see 2012 as a year of adjusted EBIT growth,” said Chairman and Chief Executive Officer Mike Thaman. “However, we continue to expect that the second half of the year will be more profitable than the first and that we will deliver strong free cash flow in 2012.

“Roofing profits remained strong, but compared negatively with the second quarter of last year due to continued high asphalt costs and competitive pressure in the marketplace,” he added. “Insulation demonstrated excellent operating leverage and significantly narrowed its losses. In addition, our Composites business made good progress in the repositioning of our European assets, the reduction of inventories and the start-up of the new melter in Mexico.”

Copyright ^© 2012 Owens Corning

Consolidated Second-Quarter 2012 Results

Stock Repurchase Activity

During the second quarter, Owens Corning repurchased 2.6 million shares of the company’s common stock for $76 million under a previously announced share repurchase program. As of June 30, 2012, 11.1 million shares remained available for repurchase under the authorized programs.

Outlook

The company’s revised adjusted EBIT expectation for the year of $360 million to $420 million reflects a weaker outlook for the year in Roofing. For 2012, the company anticipates 700,000 to 750,000 U.S. housing starts and continued growth in global industrial production.

As previously announced, the company is taking actions in its Composites segment to balance supply and to transform its Composites operation into a global network of low-delivered-cost assets. All European asset consolidations have now been announced and are on schedule. Based on the current market outlook for industrial production growth and continued progress with these actions, the company expects Composites financial performance to improve in the second half of 2012, positioning the business to return to double-digit margins in 2013.

In the Building Materials segment, the company expects another year of strong financial performance in Roofing, but with EBIT margins below 20 percent, based on the current outlook for volumes, asphalt costs and pricing. The company continues to believe Insulation will improve financial performance in the second half of the year and significantly narrow losses in 2012 on improved U.S. housing starts.

Cash taxes are expected to be about $30 million in 2012, due to the company’s $2.2 billion U.S. tax net operating loss carry forward. The company estimates a long-term effective tax rate of 25 percent to 28 percent based on the blend of effective tax rates for its U.S. and non-U.S. operations. The effective book tax rate for 2012 is expected to be about 25 percent on adjusted earnings.

The company expects general corporate expenses to be approximately $100 million in 2012. General corporate expenses include corporate staff and other activities that support the operations. Expenses will be higher in 2012 primarily due to increased pension expense.

Capital expenditures in 2012 are expected to be approximately $340 million, about 10 percent higher than depreciation and amortization, excluding the impact of the restructuring actions in Europe.

Next Earnings Announcement

Third-quarter 2012 results will be announced on Wednesday, October 24, 2012.

Second-Quarter Conference Call and Presentation

Wednesday, August 1, 2012

11 a.m. Eastern Daylight Time

Copyright ^© 2012 Owens Corning

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All Callers

Live dial-in telephone number: U.S. 1-800-706-7741 or International 1-617-614-3471

Participant passcode: 600-273-22 (Please dial in 10 minutes before conference call start time.)

Live webcast: http://www.owenscorning.com/investors

Telephone replay available through August 8, 2012: U.S. 1-888-286-8010 or International 1-617-801-6888 Participant passcode: 958-065-88

Replay of webcast also available at: http://www.owenscorning.com/investors

Presentation

To view the slide presentation during the conference call, please log on to the live webcast at www.owenscorning.com/investors

About Owens Corning

Owens Corning (NYSE: OC) is a leading global producer of residential and commercial building materials, glass-fiber reinforcements and engineered materials for composite systems. A Fortune^® 500 Company for 58 consecutive years, Owens Corning is committed to driving sustainability by delivering solutions, transforming markets and enhancing lives. Founded in 1938, Owens Corning is a market-leading innovator of glass-fiber technology with sales of $5.3 billion in 2011 and about 15,000 employees in 28 countries on five continents. Additional information is available at www.owenscorning.com.

This news release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. These forward-looking statements are subject to risks, uncertainties and other factors that could cause actual results to differ materially from those projected in these statements. Such factors include, without limitation: economic and political conditions, including new legislation or other governmental actions; levels of residential and commercial construction activity; competitive factors; pricing factors; weather conditions; our level of indebtedness; industry and economic conditions that affect the market and operating conditions of our customers, suppliers or lenders; availability and cost of energy and materials; availability and cost of credit; interest rate movements; issues related to expansion of our production capacity; issues related to acquisitions, divestitures and joint ventures; our ability to use our net operating loss carry-forwards; achievement of expected synergies, cost reductions and/or productivity improvements; issues involving implementation of new business systems; foreign exchange fluctuations; research and development activities; difficulties in managing production capacity; labor disputes; and, factors detailed from time to time in the company’s Securities and Exchange Commission filings. The information in this news release speaks as of the date August 1, 2012, and is subject to change. The company does not undertake any duty to update or revise forward-looking statements. Any distribution of this news release after that date is not intended and will not be construed as updating or confirming such information.

Copyright ^© 2012 Owens Corning

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Table 1

Owens Corning and Subsidiaries

Consolidated Statements of Earnings (Loss)

(unaudited)

(in millions, except per share amounts)

Owens Corning follows the authoritative guidance referring to “Noncontrolling Interest in Consolidated Financial Statements,” effective January 1, 2009, which, among other things, changed the presentation format and certain captions of the Consolidated Statements of Earnings and Consolidated Balance Sheets. Owens Corning uses the captions recommended by this standard in its Consolidated Financial Statements such as net earnings attributable to Owens Corning and diluted earnings per common share attributable to Owens Corning common stockholders. However, in the preceding release Owens Corning has shortened this language to net earnings and earnings per share (or a slight variation thereof), respectively.

Table 2

Owens Corning and Subsidiaries

EBIT Reconciliation Schedules

(unaudited)

For purposes of internal review of Owens Corning’s year-over-year operational performance, management excludes from net earnings attributable to Owens Corning certain items it believes are not the result of current operations. The adjusted financial measure resulting from these adjustments is used internally by Owens Corning for various purposes, including reporting results of operations to the Board of Directors, analysis of performance, and related employee compensation measures. Although management believes that these adjustments result in a measure that provides it a useful representation of its operational performance, the adjusted measure should not be considered in isolation or as a substitute for net earnings attributable to Owens Corning as prepared in accordance with accounting principles generally accepted in the United States.

Adjusting items are shown in the table below (in millions), which are related to our European restrucuturing actions:

The reconciliation from net earnings attributable to Owens Corning to Adjusted EBIT is shown in the table below (in millions):

Table 3

Owens Corning and Subsidiaries

EPS Reconciliation Schedules

(unaudited)

(in millions, except per share data)

For purposes of internal review of Owens Corning’s year-over-year operational performance, management excludes from net earnings attributable to Owens Corning certain items it believes are not the result of current operations. The adjusted financial measures resulting from these adjustments are used internally by Owens Corning for various purposes, including reporting results of operations to the Board of Directors, analysis of performance and related employee compensation measures. Although management believes that these adjustments result in measures that provide it a useful representation of its operational performance, the adjusted measures should not be considered in isolation or as a substitute for net earnings attributable to Owens Corning as prepared in accordance with accounting principles generally accepted in the United States.

A reconciliation from net earnings attributable to Owens Corning to Adjusted Earnings and a reconciliation from diluted earnings per share to adjusted diluted earnings per share are shown in the tables below:

Table 4

Owens Corning and Subsidiaries

Consolidated Balance Sheets

(unaudited)

(in millions)

Table 5

Owens Corning and Subsidiaries

Consolidated Statements of Cash Flows

(unaudited)

(in millions)

Table 6

Owens Corning and Subsidiaries

Segment and Business Information

(unaudited)

Composites

The table below provides a summary of net sales, EBIT and depreciation and amortization expense for the Composites segment (in millions):

Building Materials

The table below provides a summary of net sales, EBIT and depreciation and amortization expense for the Building Materials segment and our businesses within this segment (in millions):

Table 7

Owens Corning and Subsidiaries

Corporate, Other and Eliminations

(unaudited)

Corporate, Other and Eliminations

The table below provides a summary of EBIT and depreciation and amortization expense for the Corporate, Other and Eliminations category (in millions):