Harpers Lumber Buildings

Harpers Lumber Buildings

Roslyn, WA

SSF provided structural engineering services for the extensive renovation of the Harper’s Lumber Buildings, a historic commercial row in downtown Roslyn. After purchasing the properties in 2019, the owners faced significant deterioration from decades of deferred maintenance and moisture damage. The original buildings were constructed without conventional foundations, with wood framing directly on the soil. The project team conducted a condition assessment and developed a multi-year rehabilitation plan.

Structural upgrades focused on stabilizing the buildings, improving snow performance, and strengthening lateral systems while preserving historic character. The team submitted plans to repair deteriorated wall bases, add continuous strip footings under perimeter walls and isolated pad footings under interior posts, and upgrade the lateral system. Following a year of record snowfall in 2021, the design was refined to relocate the old saw shop farther back on the lot and to reframe Building 2 with a flat roof designed to hold snow rather than shed it into the narrow spaces between buildings. The roof rafters, bearing walls, and footings were sized for Roslyn’s code-level snow loads. Exterior walls were sheathed with plywood and anchored to the new foundations with anchor bolts and hold-downs. Along Pennsylvania Avenue, a steel moment frame was added at the front elevation where there was little existing wall length, allowing the storefront to meet lateral requirements while maintaining its historic appearance.