The Irving R. Newhouse building on the Washington State Capitol Campus has earned a Platinum certification from Leadership in Energy and Environmental Design (LEED). The Department of Enterprise Services (DES) led the project to replace the original Newhouse building.

"We are excited that Newhouse has earned LEED Platinum certification," said DES Director Matt Jones. "The building's design honors the history of the Capitol Campus, while integrating progressive energy-saving features that embrace Washington's ongoing commitment to minimizing our impact on the environment."

LEED is the most widely used green building rating system in the world. Only 10% of applicants achieve Platinum certification, the highest level.

Two other buildings on Capitol Campus are LEED Platinum certified: Helen Sommers Building and 1500 Jefferson. Two are Gold certified: Capitol Childcare Center and John L. O'Brien.

The state Legislature in 2021 stipulated that the building to achieve at least LEED Silver certification. The features that contributed to the Platinum certification include:

• The building is 100% electric; roof-mounted solar panels generate about 20% of its power. It's also net-zero carbon emissions ready, which means it's designed so that additional sources of renewable energy can be added later.
• It features a green roof that contributes to the building's environmental sustainability with energy efficiency, less rainwater runoff and improved air quality.
• Most of the new building materials were sourced in Washington and reflect the commitment to sustainability and resource stewardship. Mass timber—large pre-manufactured, multilayered, solid wood panels—is at the center of the building's low carbon footprint.
• The project repurposed materials salvaged from the original Newhouse building and the nearby press houses that were dismantled.
• Newhouse is the first known building in the United States to feature Acoustic Dowel Laminated Timber (ADLT), which eliminates all known chemicals of concern that are used in traditional acoustic insulation.

Read more about the features in the Newhouse building.

Completed in 1934 as a temporary structure, the original Newhouse building had far exceeded its useful life, posing significant health and safety hazards. Designed by Miller Hull Partnership LLP, DES completed the Newhouse building as part of the Legislative Campus Modernization project in December 2024. Occupants include members of the Senate, their staff and Legislative Support Services.

Legislative Campus Modernization (LCM) is a series of construction projects on the Capitol Campus that address space needs of legislative agencies and critical issues with the Irving R. Newhouse, Joel Pritchard and John L. O'Brien buildings. Projects will continue through the end of 2026.

The Department of Enterprise Services provides daily care and long-term planning for the Washington State Capitol Campus, balancing the needs of state government with public access and historic preservation. The Capitol Campus is the seat of Washington state government and welcomes more than 400,000 visitors each year.