The renovation and extension of the Southwest Branch Library was made possible as part of the Libraries for All initiative, approved by Seattle voters in 1998. The $196 million bond measure enabled library renovations and new library construction.

The Southwest Branch building, completed in 1961, was doubled in size to 15,000 square feet. Much of the existing steel structure from the original brick-clad, one-story building was preserved.

The library expansion extends the original building to the street with a two-story addition and entry arcade, increasing the building’s civic presence. The addition is clad in a wood-resin composite panel system. The rebuilt original portion of the building is covered in durable and low-maintenance corrugated cement board.

The renovated library features abundant fenestration, opening the building to light and the surrounding neighborhood. Clerestory windows and a central light well surround the vertical circulation area, bringing natural light deep into the building’s center.

A displacement ventilation system provides natural ventilation—there is no air conditioning—and the central, two-story circulation space and clerestories help release excess heat.

Interior beech wood veneers create a warm and inviting space. British Columbia artist, Katherine Kerr, created an exterior installation piece of outstretched hands, cast from the hands of some of the library’s most active patrons.


Seattle Public Library System

Olson Sundberg Kundig Allen Architects
159 South Jackson Street, Suite 600
Seattle, WA 98104
P: 206-624-5670
F: 206-624-3730

Personnel in architect's firm who should receive special credit:
Rick Sundberg, FAIA, LEED AP, Principal-in-charge
Janice Wettstone, AIA, Associate
Olivier Landa, LEED AP, Project Manager
Leanne Christ, Project Architect
Debbie Kennedy, Interior Designer

Interior designer:
Olson Sundberg Kundig Allen Architects

Structural: Monte Clark Engineering

Mechanical: Greenbusch Group

Electrical: Sparling

A/V: Sparling

Acoustical: Greenbusch Group

Civil: Coughlin Porter Lundeen

Landscape: Swift and Company

Lighting: Candela

Furniture and Fixture: Design Perspectives

Artist: Katherine Kerr

General contractor:
Construction Enterprises & Contractors

CAD system, project management, or other software used: AutoCad





Structural system:
Steel Structure

Exterior cladding:
Wood Resin Composite Panels: Prodema

Corrugated Cement Panels: Cembonit B9 by Cembrit

Single Ply Membrane: Sarnafil

Aluminum: Vistawall

Glass: PPG Solar Ban 60 Low-E, Argon filled

Skylights: DeaMore

Entrances: Vistawall

Interior finishes:
Acoustical ceilings: USG 1’x1’ glue on tile

Cabinetwork and custom woodwork: Custom Beech Veneer Cabinets with Concrete countertops

Paints and stains: Sherwin Williams

Paneling: Prodema Wood Resin Composite Panel

Carpet: Interface Carpet Tile (90% Recycled)

Raised flooring: Tate Access Floor

Stairs: Glue Laminated wood treads with Galvanized Steel Risers

Add any additional building components or special equipment that made a significant contribution to this project: 

Sustainable building systems and components

Cladding System: cladding system was vented to reduce heat gain inside the building.

The primary level of the building has a displacement ventilation system.  The raised floor system distributes fresh air through over 100 floor diffusers. The outside air is cooled by the ambient temp of the earth. The outside air runs through underground ducts and then moved across a slab on grade as it is distributed through the raised floor system. Air is vented out of a 30’ long light and ventilation roof monitor and three bays of electrically operated clerestory windows.

Glazing exposure:
South and West facing windows were minimized.

Window type:
The windows are thermally broken window frames with double pane low-e and argon filled glazing was used in order to minimize heat gain during the summer and minimize heat loss during the winter.

Lighting Control system:
a lighting control system was used which shuts off all lights which are within 15’ of a window when sufficient natural light is coming into the building and light fixtures were chosen to minimize heat gain.

Roofing material:
The roof membrane is Energy Star rated. roof membrane was used to minimize heat gain during the summer.  The membrane is white which makes reflect heat and because it reflects heat the membrane will last longer than darker colored membranes. Additionally the roof membrane is 100% recyclable.

In an effort to save water, drought tolerant plants were used so that the irrigation system will only have to be used for the first two years after the landscape was installed. 

Demolition Recycling:
All concrete and steel from the demolition was recycled.

The carpet tiles are made from recycled materials.