Exhibit 99.1

Owens Corning Reports First-Quarter 2011 Results

First Quarter in Line with Company’s Expectations;

On Target to Deliver $475 Million in Adjusted EBIT in 2011

TOLEDO, Ohio – April 27, 2011 – Owens Corning (NYSE: OC) today reported consolidated net sales decreased 2 percent to $1.24 billion in the first quarter of 2011, compared with $1.27 billion in the first quarter of 2010.

First-quarter 2011 net earnings were $24 million, or $0.19 per diluted share, compared with net earnings of $48 million, or $0.38 per diluted share, in the first quarter of 2010. First-quarter adjusted earnings, when adjusted to the company’s expected full-year effective tax rate of 28 percent, were $25 million, or $0.20 per diluted share, compared with $53 million, or $0.42 per diluted share, in the first quarter of 2010. (See Tables 1, 2 and 3 for a discussion and reconciliation of these items.)

“Owens Corning delivered profit in line with our expectations for the first quarter driven by continued strong performance in the Composites and Roofing businesses,” said Chairman and Chief Executive Officer Mike Thaman. “We remain confident in our guidance of $475 million in adjusted EBIT for 2011.

“During the quarter we made operating investments to expand our Composites capacity and convert Insulation facilities to produce our new EcoTouch™ insulation,” Thaman added. “We expect that these investments – combined with improving economic conditions and our recent pricing actions – will improve profitability throughout the balance of the year.”

Consolidated First-Quarter 2011 Results

Reinforcements Plant Divestiture

During the first quarter, Owens Corning reached a definitive agreement to sell its glass fiber reinforcements plant in Capivari, Brazil. The transaction, which is expected to close during the second quarter of 2011, is subject to regulatory approval and other customary conditions.

Outlook

Owens Corning today reaffirmed that 2011 adjusted EBIT is expected to grow to $475 million. This translates to adjusted earnings per share (EPS) growth of more than 30 percent. The company expects to benefit from revenue and margin growth while continuing to maintain discipline in managing headcount and operating costs.

In the Composites segment, the company believes that sales volume will continue to trend upward as global industrial demand increases throughout 2011. The company’s new Reinforcements facility in China and other investments in facilities that took place in the quarter are expected to begin contributing to profitability in the second quarter of 2011. In addition, the company expects to complete the expansion of its Russian facility by the end of 2011.

In the Building Materials segment, continued weakness in the U.S. housing industry is expected to impact construction-related demand throughout 2011. The company expects U.S. new residential construction to improve modestly in the second half of 2011.

While the roofing market continues to operate well below its potential, the company believes full-year EBIT margins of 20 percent are achievable for this business in 2011.

The Insulation business is expected to benefit from improving market conditions and volume as the year progresses. The company expects the EcoTouch™ plant conversions to be substantially complete in the second quarter and to return this business to profitability in the second half of the year.

Cash taxes are expected to be less than $30 million in 2011. 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 2011 is expected to be 28 percent.

General corporate expense in 2011 is estimated to be between $80 million and $90 million. General corporate expense includes corporate staff and other activities that support the operations.

Depreciation and amortization expense will be approximately $340 million in 2011.

Copyright © 2011 Owens Corning

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Capital expenditures in 2011 are expected to total approximately $400 million.

Other Financial Items

Business Segment Highlights

Composites

NET SALES

Net sales increased during the first quarter of 2011 compared to the same period in 2010. More than half of the increase in net sales was the result of higher selling prices during the quarter. The upward trend in selling prices that began in the fourth quarter of 2009 continued during the first quarter of 2011. As a result, selling prices of key product groups within the Reinforcements business have returned to levels seen prior to the 2008 global economic downturn. Favorable currency translation and favorable product mix each accounted for about one-third of the increase in 2011 sales versus 2010. These impacts were partially offset by lower sales volumes, primarily in Asia Pacific, in first quarter of 2011 as compared to the same period in 2010.

EBIT

EBIT for the first quarter of 2011 increased 55 percent compared with the same period in 2010. Higher selling prices and production leverage each had about the same positive impact on EBIT. These items were partially offset by material and energy inflation costs as well as increases in selling, general and administrative expenses.

Copyright © 2011 Owens Corning

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Building Materials

NET SALES

Net sales in the Building Materials segment were lower in the first quarter of 2011 compared with the same period in 2010. Most of this decrease was related to lower sales volumes within the Roofing business. Sales were also negatively impacted by the fourth quarter 2010 divestiture of the North American Masonry Products business and lower sales in the Insulation business.

In the Roofing business, lower shingle volumes accounted for approximately three-fourths of the decrease in net sales during the quarter. First-quarter 2011 shingle volumes were lower than the first quarter of 2010 because of heavier customer restocking activity in first quarter of 2010. The remaining decrease in net sales between the first quarter of 2011 and the first quarter of 2010 was due to lower selling prices, which more than offset favorable product mix.

In the Insulation business, net sales in the first quarter of 2011 were lower than the same period in 2010 due to lower sales volumes that were partially offset by higher selling prices. Lower sales volumes continue to persist given the current state of the U.S. housing market. Pricing actions taken in the United States in the second half of 2010 resulted in higher selling prices in the first quarter 2011 as compared to the first quarter of 2010.

EBIT

EBIT for the Building Materials segment decreased in the first quarter of 2011 compared with the same period in 2010 primarily because of lower EBIT in the Roofing business.

In the Roofing business, approximately three-fourths of the decrease in EBIT for the first quarter of 2011 compared to first quarter of 2010 was due to lower unit margins. Lower selling prices and raw material inflation including asphalt, negatively impacted first-quarter 2011 unit margins compared to the first quarter of 2010. The remaining decrease in EBIT was due to lower shingle sales volumes as described above.

In the Insulation business, EBIT was down for the first quarter of 2011 compared with the same period in 2010. Increases in United States selling prices were more than offset by the impact of lower sales volumes and costs associated with the launch of EcoTouch™ during the first quarter.

Copyright © 2011 Owens Corning

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Next Earnings Announcement

Second-quarter 2011 results will be announced on Wednesday, August 3, 2011.

Conference Call and Presentation

Wednesday, April 27, 2011

11 a.m. Eastern

All Callers

Live dial-in telephone number: U.S. 1-866-730-5770 or International 1-857-350-1594

Passcode: 70753258

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

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

Telephone replay available through May 4, 2011: U.S. 1-888-286-8010 or International 1-617-801-6888

Passcode: 15410786

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 56 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 $5.0 billion in 2010 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 27, 2011 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 © 2011 Owens Corning

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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. Prior period amounts have been recast to reflect the inclusion of the Construction Services and Building Materials Europe businesses within Insulation. Other consists of Masonry Products.