Exhibit 99.1

Owens Corning Reports First-Quarter 2012 Results

First Quarter in Line with Company’s Expectations;

On Target for Adjusted EBIT Growth in 2012

TOLEDO, Ohio – April 25, 2012 – Owens Corning (NYSE: OC) today reported that consolidated net sales increased 9 percent to $1.35 billion in the first quarter of 2012, compared with $1.24 billion in the same period last year.

First-quarter 2012 adjusted earnings, based on the company’s expected full-year effective tax rate of 25 percent, were $11 million, or $0.09 per diluted share, compared with $27 million, or $0.22 per diluted share, during the same period last year. The company reported a net loss of $46 million, or $0.38 per diluted share, compared with net earnings of $24 million, or $0.19 per diluted share, in the first quarter of 2011. (See Tables 1, 2 and 3 for a discussion and reconciliation of these items.)

“Owens Corning delivered results in line with our expectations for the quarter,” said Chairman and Chief Executive Officer Mike Thaman. “We continue to be confident that we will grow adjusted EBIT in 2012.

“As compared to last year, Roofing volumes grew significantly, but margins were compressed due to asphalt cost inflation,” Thaman said. “We expect another year of strong financial performance in Roofing based on our current outlook for volumes and pricing.”

Copyright © 2012 Owens Corning

Consolidated First-Quarter 2012 Results

2012 Repurchase Program

Owens Corning today announced that its Board of Directors has authorized the company to repurchase up to 10 million additional shares of Owens Corning’s outstanding common stock. Under a previously announced share repurchase program, 3.7 million shares continue to be available for repurchase.

Outlook

Although there continues to be uncertainty in the macro-economic outlook, Owens Corning expects to grow adjusted EBIT in 2012 based on an improving U.S. housing market and continued growth in global industrial production.

Despite weakness in the European glass fiber reinforcements market, the company believes that global glass reinforcements demand will continue to grow in 2012.

As previously announced, the company is taking actions in its Composites segment to balance supply and to improve the sustainable competitive position of its European assets. In the first quarter, the company made progress in implementing these actions to transform its Composites operation into a global network of low-delivered-cost assets and to position the business to return to double-digit margins in 2013. In conjunction with these actions, the company anticipates incurring approximately $130 million in charges in 2012 through early 2013.

In the Building Materials segment, the company expects another year of strong financial performance in Roofing based on its current outlook for volumes and pricing. The company continues to believe Insulation will significantly narrow losses in 2012 on improved U.S. housing.

Cash taxes are expected to be about $30 million in 2012, due to the company’s $2.3 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 between $110 million and $120 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 and higher year-over-year incentive compensation costs.

Depreciation and amortization expenses are expected to be as much as $320 million in 2012, excluding the impact of the restructuring actions in Europe. Capital expenditures in 2012 are expected to be about $350 million.

Copyright © 2012 Owens Corning

2

Next Earnings Announcement

Second-quarter 2012 results will be announced on Wednesday, August 1, 2012.

First-Quarter Conference Call and Presentation

Wednesday, April 25, 2012

11 a.m. Eastern Daylight Time

All Callers

Live dial-in telephone number: U.S. 1-866-804-6924 or International 1-857-350-1670

Passcode: 80163255

(Please dial in 10 minutes before conference call start time.)

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

Telephone replay available through May 2, 2012: U.S. 1-888-286-8010 or International 1-617-801-6888

Passcode: 84632337

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 57 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 April 25, 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

3

Table 1

Owens Corning and Subsidiaries

Consolidated Statements of Earnings

(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):

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 (in millions) 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):