Creating a Quiet Urban Community

2200 Westlake Block
Collins Woerman Architects, Milliken Developers & Vulcan

2200 Westlake Block is a 975,000 sq ft, three-structure project which includes  hotel and residential units above commercial and retail spaces. The structures encompass a grocery store, 270 living units, 126 five-star hotel rooms, retail space, offices, and 672 parking spaces.  With a projected completion date of fall 2004, this project is a cornerstone of urban transformation for Seattle’s South Lake Union neighborhood.

Challenges: Concentrating rooftop mechanical equipment on one area creates noise challenges due to airborne noise and vibration transmitted as noise to the structure. Sensitive penthouse units also required special care in design in order to prevent intrusive noise from the rooftop mechanical equipment. The courtyard area located above the garage and grocery store also required special care in design.

Solutions:  We have provided acoustical input in relation to building layout, wall types, and equipment locations. From demising walls and plumbing noise to impact isolation of floor/ceiling assemblies, we have provided detailed recommendations to achieve acceptable NC levels.  Noise levels from rooftop mechanical units to neighboring properties were predicted using AutoCAD, and exhaust fan noise had to be quieted for code compliance, as well as resident comfort, in the courtyard.

Additional Involvement:   Hood exhaust from the restaurant required heavy gauge ductwork, rigidly attached to the fans. Isolation down through the structure was required to prevent noise from going to commercial and residential spaces. Heat pumps will be reviewed for quality with the mechanical engineer before installation.