Owens Corning

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13. STOCK COMPENSATION

Description of the Plan

On April 20, 2023, the Company’s stockholders approved the Owens Corning 2023 Stock Plan (the “2023 Stock Plan”), which authorizes grants of stock options, stock appreciation rights, stock awards (including restricted stock awards, restricted stock units and bonus stock awards), performance share awards and performance share units. At March 31, 2024, the number of shares remaining available under the 2023 Stock Plan for all stock awards was 3.0 million.

Prior to the 2023 Stock Plan, employees were eligible to receive stock awards under the Owens Corning 2019 Stock Plan.

Total Stock-Based Compensation Expense

Stock-based compensation expense included in Marketing and administrative expenses in the accompanying Consolidated Statements of Earnings is as follows (in millions):

Restricted Stock Units

The Company has granted restricted stock units (“RSUs”) under its stockholder-approved stock plans. Generally, all outstanding RSUs will fully settle in stock. Compensation expense for RSUs is measured based on the closing market price of the stock at date of grant and is recognized on a straight-line basis over the vesting period, which is typically three tofour years. The Stock Plan allows alternate vesting schedules for death, disability, and retirement. The weighted-average grant date fair value of RSUs granted in 2024 was $154.72.

The following table summarizes the Company’s RSU activity:

As of March 31, 2024, there was $62 million of total unrecognized compensation cost related to RSUs. That cost is expected to be recognized over a weighted-average period of 2.29 years. The total grant date fair value of shares vested during the three months ended March 31, 2024 and 2023 was $23 million and $22 million, respectively.

Performance Share Units

The Company has granted performance share units (“PSUs”) as a part of its long-term incentive plan. All outstanding PSUs will fully settle in stock. The amount of shares ultimately distributed from all PSUs is contingent on meeting internal company-based metrics or an external-based stock performance metric.

In the three months ended March 31, 2024, the Company granted both internal company-based and external-based metric PSUs.

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13. STOCK COMPENSATION (continued)

Internal Company-based metrics

The internal Company-based metric PSUs are based on various Company metrics and typically vest after athree-year period. The amount of stock distributed will vary from 0% to 200% of PSUs awarded depending on each award’s design and performance versus the company-based metrics.

The initial fair value for all internal company-based metric PSUs assumes that the performance goals will be achieved and is based on the grant date stock price. This assumption is monitored quarterly and if it becomes probable that such goals will not be achieved or will be exceeded, compensation expense recognized will be adjusted and previous surplus compensation expense recognized will be reversed or additional expense will be recognized. The expected term represents the period from the grant date to the end of the three-year performance period. Pro-rata vesting may be utilized in the case of death, disability or retirement and awards, if earned, will be paid at the end of thethree-year period.

The following table provides a summary of the grant date fair values of the internal Company-based metric PSUs:

External-based metrics

The external-based metric PSUs vest after athree-year period. Outstanding grants issued in or after 2018 until 2022 were based on the Company’s total stockholder return relative to the performance of the Dow Jones U.S. Construction & Materials Index. Outstanding grants issued in or after 2023 are based on the Company’s total stockholder return relative to a peer group. The amount of stock distributed will vary from 0% to 200% of PSUs awarded depending on the relative stockholder return performance. The fair value of external-based metric PSUs has been estimated at the grant date using a Monte Carlo simulation that uses various assumptions.

The following table provides a summary of the assumptions for PSUs granted in 2024 and 2023:

The risk-free interest rate was based on zero-coupon United States Treasury STRIPS at the grant date. The expected term represents the period from the grant date to the end of thethree-year performance period.

PSU Summary

As of March 31, 2024, there was $27 million total unrecognized compensation cost related to PSUs. That cost is expected to be recognized over a weighted-average period of 2.09 years.

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13. STOCK COMPENSATION (continued)

The following table summarizes the Company’s PSU activity:

Employee Stock Purchase Plan

The Owens Corning Employee Stock Purchase Plan (“ESPP”) is a tax-qualified plan under Section 423 of the Internal Revenue Code. The purchase price of shares purchased under the ESPP is equal to 85% of the lower of the fair market value of shares of Owens Corning common stock at the beginning or ending of the offering period, which is asix-month period ending on May 31 and November 30 of each year. On April 16, 2020, the Company’s stockholders approved the Amended and Restated Owens Corning Employee Stock Purchase Plan, which increased the number of shares available for issuance under the plan by 4.2 million shares. As of March 31, 2024,3.2 million shares remain available for purchase.

Included in total stock-based compensation expense is $2 million of expense related to the Company’s ESPP recognized during the three months ended March 31, 2024. During the three months ended March 31, 2023, the Company recognized expense of $2 million related to the Company’s ESPP. As of March 31, 2024, there was $1 million of total unrecognized compensation cost related to the ESPP.