City of Seattle ADUniverse · 10 plans
Every one of the City of Seattle’s 10 pre-approved DADU floor plans, on one page — size, beds, baths, footprint, and construction system, so you can shortlist before you license a $750–$1,000 plan set. Two of the ten use off-site systems, three are published as conventional wood frame, and the gallery does not state a construction system for the remaining five — ask the designer before assuming. All of them still have to fit your lot.
Plan statistics and images are from the City of Seattle’s ADUniverse pre-approved DADU gallery (fetched 2026-09-16). The City pre-reviews the design, not your lot.
Image: Mobile Office Architects via City of Seattle ADUniverse · Full plan page
Image: Magellan Architects via City of Seattle ADUniverse · Full plan page
Image: Yes Architecture via City of Seattle ADUniverse · Full plan page
Prefab / panelized
Image: Bohlin Cywinski Jackson via City of Seattle ADUniverse · Full plan page
Image: Shape Architecture via City of Seattle ADUniverse · Full plan page
Image: CAST Architecture via City of Seattle ADUniverse · Full plan page
Image: Fivedot Architects via City of Seattle ADUniverse · Full plan page
Image: Ahouse Studio via City of Seattle ADUniverse · Full plan page
Prefab / panelized
Image: HAAS Building via City of Seattle ADUniverse · Full plan page
Image: Artisans Group via City of Seattle ADUniverse · Full plan page
Prefab DADUs in Seattle
Two of the ten plans use off-site systems: the Urban Cottage (a panelized kit of pre-cut structural insulated panels) and the Edge House (a quick-ship kit assembled around a bolted steel frame from off-the-shelf components). Of the rest, three are published as conventional wood frame, framed on site; the gallery does not state a construction system for the other five, and this page does not guess one.
Two things worth knowing before you pay a premium for “prefab.”
None of this changes the one question that actually decides a project: whether a plan’s footprint fits your measured buildable rectangle. The plan-fit report tests all 10 footprints against your lot — and the setback requirements are the rules it is measured against.
Next step
Pick a favorite above, then run it against your lot. The plan-fit report measures your buildable rectangle from the parcel boundary and building outlines, then tests all 10 published footprints in both orientations. Prefer to self-study? The Pro Guide walks the same rules.
The City of Seattle publishes 10 pre-approved DADU plans in its ADUniverse gallery. This page lists all of them with size, beds, baths, footprint, construction system, designer, and plan-set price. You license a plan directly from its designer, then use it for the pre-approved permit path.
The plans themselves are not free to build from — each designer charges a plan-set license, typically $750 to $1,000. Browsing the catalog and this page is free. The plan-set price is published on each designer's page and shown on each card below.
Two of the ten are off-site systems: the Urban Cottage is a panelized kit of structural insulated panels (SIPs), and the Edge House is a quick-ship kit built around a bolted steel frame. Of the remaining eight, three are published as conventional wood-frame site-built plans and the gallery does not state a construction system for the other five. Even the two prefab kits are assembled on site on a permanent foundation — none arrive as a finished unit on wheels.
Yes. Pre-approved means the design is pre-reviewed, not that your lot is approved. You still submit a site plan, foundation design, and utility paperwork to SDCI through the Seattle Services Portal. On an eligible lot, a pre-approved plan can shorten plan review — SDCI says as quickly as 2–6 weeks for most sites.
That is a measured question, not a guess. The Pre-Approved DADU Plan Fit report tests all 10 published footprints against your lot's buildable rectangle in both orientations. It is the fastest way to go from "I like this plan" to "this plan fits my yard."