Seattle Building Permits for Home Projects

Rules for the most common home projects in Seattle, Washington, checked against the Seattle Department of Construction and Inspections (SDCI)'s own pages, with live permit counts from the city's open data.

13,214permits in 12 months (tracked projects)
4project types with verified rules
HVACmost common tracked project

Do You Need a Permit? Project by Project

Seattle Roofing Permits

Often no455 in 12 mo

For detached one- and two-family homes, re-roofing and replacing sheathing needs no permit when the building envelope does not change and the work is equal to or better than what exists.

Seattle HVAC Permits

Yes12,661 in 12 mo

Furnaces and heat pumps need a mechanical (furnace) permit in Seattle, and split systems with refrigerant piping also need a refrigeration permit, which only a licensed contractor can get.

Seattle Fence Permits

Usually no10 in 12 mo

No permit is needed for a fence up to 8 feet total height without masonry or concrete elements over 6 feet, unless it is in a flood-prone area.

Seattle Deck Permits

Sometimes88 in 12 mo

You need a construction permit for a deck more than 18 inches above the ground or any roof deck.

Permit Activity in Seattle

927 Nov 1169 Dec 904 Jan 876 Feb 1189 Mar 1171 Apr 1081 May 1290 Jun 1239 Jul 1042 Aug 994 Sep 1277 Oct
Tracked home project permits issued per month in Seattle. Lighter bar = current month to date.

Projects We Have Not Verified Yet

We track permit data for solar work in Seattle but have not yet verified the official rule (or there were fewer than 10 permits), so we do not publish a page for it.

Seattle Permit Guides

Seattle Contractors: Get Weekly Permit Lists

Contractors: get new permits for your trade and city every Monday. Join the waitlist.

Frequently Asked Questions

Who issues building permits in Seattle?

The Seattle Department of Construction and Inspections (SDCI).

Which home projects need a permit in Seattle?

Roofing: often no; HVAC: yes; Fence: usually no; Deck: sometimes. Each project page explains the exact rule and links the official source.

How many home improvement permits does Seattle issue?

Across the 4 project types we track, Seattle issued about 13,214 permits in the last 12 months. HVAC was the most common, with 12,661.

Written and maintained by the Home Permit Guide Editorial TeamPlaceholder profile

Reviewed by: named reviewer to be added · Last updated

This is a placeholder editorial profile. A named reviewer with verifiable experience will be added here. Until then, every rule on this page links to the official government source it was checked against. Read our editorial policy.

Sources

Official sources checked on . Rules change; confirm with the department before you start work.

  1. Seattle SDCI: Re-Roof Permit (seattle.gov)
  2. Seattle SDCI: Do You Need a Permit? (seattle.gov)
  3. Seattle SDCI: Furnace & Refrigeration Permits (seattle.gov)
  4. Seattle SDCI: Mechanical Permit (seattle.gov)
  5. Seattle SDCI: Fences (seattle.gov)
  6. Seattle SDCI Tip 312: Decks, Fences and Arbors (seattle.gov)

Permit data: Seattle Building Permits, refreshed October 30, 2026.