RDH, serving as the Architect of Record in collaboration with GGLO, led a full exterior wall rehabilitation to improve the building’s envelope performance and extend its service life. The project replaced the original stucco cladding with a higher-performing wall assembly that significantly improved waterproofing, air barrier continuity, and thermal performance.
The rehabilitation included new plywood sheathing, a liquid-applied water-resistive air barrier, and a continuous layer of 1 ¼” high-density mineral wool insulation. This assembly was clad with fiber-cement siding, providing a 1-hour fire rating from both the interior and exterior, as well as between floors.
To secure approval for the assembly, RDH prepared and submitted a Code Modification Request demonstrating compliance with the intent of the 2006 Seattle Building Code (Sections 720 and 721.6 for fire-resistance-rated wood assemblies and Sections 104.9 and 104.10 for alternate materials and methods). This approach increased the building’s fire safety while delivering thermal and durability benefits.
Tatley-Grund served as the builder for the project, which was designed to minimize disruption to residents while achieving significant long-term performance improvements.
