Douglas Truth Library

The addition’s copper skin and curtain-wall glazing contrast sharply with the historic building’s brick and terra-cotta wall cladding and clay-tile roof.

A grass-planted green-roof over a sub-grade portion of the library blends invisibly with the site’s landscaping.

Seattle, Washington
Client: Schacht-Aslani Architects
Dates of Service: 2001-2007

Project Summary: This project involved a major expansion of a historic Carnegie Library building on a tight, urban lot. Rather than attempting to mimic the architecture of the existing masonry building, Schacht-Aslani Architects designed a contrasting addition with copper roof and wall cladding, pre-cast concrete panels, and aluminum curtain-wall glazing. To minimize impact on the small site, a significant part of the addition was placed below grade, requiring careful waterproofing of its sub-grade walls and planted roofs.

PL:BECS Services: PL:BECS services consisted of two distinct tasks.

The first was the evaluation of the building’s original wood windows to determine which of these could be salvaged and which were too degraded, requiring replacement with new, custom-fabricated windows to match the existing historic profiles.

The second phase included assisting the architect in designing the addition, including selection of appropriate exterior assemblies, waterproofing and cladding products and materials, and input into selected exterior details.

Reinforced hot-rubber waterproofing was selected for the extensive sub-grade roofs, in combination with bentonite waterproofing on the sub-grade walls.

To facilitate drainage of condensation from under the copper roof and wall cladding, the copper panels were installed over a thin vent mat, with a self-adhered ice-and-water shield membrane under the copper roofing.

Individual windows, curtain-wall glazing, as well as a large continuous skylight were designed to bring light into the subterranean reading rooms.