505 First, a 288,000-square-foot Class A office building in the Pioneer Square neighborhood of Seattle, is the first existing building to obtain the highly rigorous Core Green Building certification from the International Living Future Institute (ILFI). Blending modern technology with historic architecture, 505 First boasts exceptional amenities, including a rooftop deck with panoramic views of downtown Seattle and the Puget Sound, while setting a new standard for sustainability and innovation.