Seattle, WA Building Safety: Scaffold & Sidewalk Shed (2026)

Scaffolding in Seattle is regulated by both the Seattle Building Code (administered by SDCI) and SDOT for structures in the public right-of-way. A Street Use permit from SDOT is required for any scaffolding that extends over or occupies a public sidewalk, street, or alley. The permit application must include engineered drawings showing scaffold design, anchorage, and pedestrian protection measures. Scaffolding must comply with the Washington Industrial Safety and Health Act (WISHA, RCW 49.17) and Washington Administrative Code (WAC 296-874) fall protection and scaffolding standards, which align with federal OSHA regulations (29 CFR 1926 Subpart L). All scaffolds must be erected, modified, and dismantled under the supervision of a competent person. Guardrails, toeboards, and personal fall protection are required on scaffold platforms above 10 feet. Regular inspections are required before each work shift and after any event that could affect structural integrity. Scaffold-mounted sidewalk sheds are required when work above pedestrian areas could create falling object hazards.