Seattle has thousands of Craftsman bungalows, colonial revivals, mid-century ranch homes, and other older homes that homeowners want to expand. Adding to a historic home requires sensitivity — both to the existing architecture and to the regulatory environment.
The Design Principle: Compatible but Distinguishable
The Secretary of the Interior’s Standards for Rehabilitation — the national guide for historic preservation work — advises that new additions should be “compatible with the historic character of the property” but “differentiated” from the original so the addition is recognizable as new construction. In practice, this means matching scale, massing, and rhythm without directly copying historic details.
Is Your Home a Designated Landmark?
If your home is designated as a Seattle landmark, all exterior changes require a Certificate of Approval from the Landmarks Preservation Board. Additions must be reviewed for compatibility with the building’s significant features. This adds 4-12 weeks to the permit process.
Non-Landmark Historic Homes
Homes that are architecturally significant but not formally designated have no regulatory protection on additions — but good design practice still calls for a thoughtful approach. A well-designed addition enhances the home’s value and character; a poorly designed addition detracts from both.
Common Addition Strategies for Older Seattle Homes
- Rear additions that maintain the front facade intact
- Second story additions set back from the front to reduce massing impact
- Dormers that add attic space without changing the roofline dramatically
- Garage ADUs that use compatible materials but contemporary detailing
Cost Considerations
Historic homes often have hidden surprises — knob-and-tube wiring, lead paint, asbestos, non-standard framing — that add cost to renovation and addition work. Budget a 15-20% contingency for projects on pre-1960 homes.
Piper Cole Architects has extensive experience with additions to Seattle’s older housing stock. Free consultation — call 425-753-6452.
Ready to Start Your Project?
Piper Cole Architects offers a free initial consultation for all project types — residential, commercial, ADU, and renovation. No obligation. Based in Kirkland, WA. Serving the entire Seattle metro area since 2000.