Seattle windows: compare the opening, not just the glass

Questions covered in this guide

Local considerations

For Seattle window projects, pair each product choice with a description of the opening and surrounding work. Keep permit questions visible by window number instead of treating a small order as a blanket exemption.

A window count alone misses differences in the surrounding work and the opening’s function. The room schedule helps a homeowner compare like scopes and directs safety or code questions to a qualified professional.

Explore the national planning guide

Start with what will change

Seattle's permit guidance identifies building-envelope changes and work reducing egress, light, ventilation or fire resistance as requiring a permit regardless of project size. It also states that exempt work must meet applicable standards. Do not interpret a small window order as proof that review is unnecessary. Ask SDCI or your project professional to confirm the route for the actual scope.

Build a room and opening worksheet

Number the windows on a simple room sketch. For each one, write the reason for the project: a damaged frame, difficult operation, unwanted sound or another concern. Add a separate field for what the contractor proposes to change: the window unit, the surrounding frame, the wall opening or the operating style. Keep observations and proposed work in different columns so a product substitution does not silently change the project.

Ask about the usable opening

For a bedroom or another opening with a safety function, request the professional's written assessment of the proposed unit in its installed condition. Ask for the relevant dimensions and explanation rather than attempting to establish compliance from a catalog photograph. Have the bidder identify who will verify the room's requirements and any effect of installation details. Include those responsibilities in the written scope before ordering.

Normalize the bids by opening

Compare proposals using the same numbered schedule, including trim, finishing and disposal responsibilities. Mark which openings still need a permitting decision. Confirm the property's jurisdiction separately from its Seattle mailing address. The window calculator provides national planning figures and does not determine a Seattle permit exemption, select a compliant escape opening or price wall alterations. Use the worksheet to obtain an itemized proposal and resolve the remaining scope questions with the installer.

Sources and supported claims

Seattle requires permits for building-envelope changes or work reducing egress, light, ventilation or fire resistance, regardless of project size.
Source ↗ · place · Checked 2026-10-12

Seattle states that work exempt from a permit must still meet code requirements and development standards.
Source ↗ · place · Checked 2026-10-12