Get a free quote

Get a free quote from a licensed local Spokane ADU builder

Share a few details about your lot and project. It is free to you, we are paid by the builder, and there is no obligation.

Backyard accessory dwelling unit cottage in Spokane, Washington

Get a free quote from a Spokane ADU builder

Tell us about your project. A builder who serves your jurisdiction prices it, free and with no obligation.

Name

Phone

Your jurisdiction

Project type

Property address or nearest cross-streets (optional)

Helps the builder check what your specific lot can support. Skip it if you would rather not share it yet.

Lot or timeline notes (optional)

By submitting this form, I agree that Lilac City ADU and an ADU builder may contact me at the phone number and email I provided, including by automated phone calls and prerecorded messages, regarding ADU services. Consent is not a condition of any purchase. Message and data rates may apply. I may opt out at any time by asking to be removed during any call. See the Terms and TCPA disclosures and the Privacy policy.

We do not promise a specific price, timeline, financing approval, or permit outcome.

What happens after you submit

Your request goes to a licensed local builder who serves your jurisdiction.
The builder follows up to discuss your project directly.
You decide whether to proceed. You contract with the builder, not with us.

Still weighing it up? Our guide on whether you can build an ADU on your lot walks through zoning, setbacks, and utilities before you commit.

We do not promise a specific price, timeline, financing approval, or permit outcome.

What it costs, and what happens after you send it

What does an ADU cost in the Spokane area?: detached new-build $110,000 to $260,000, garage conversion $50,000 to $120,000, prefab or modular installed $80,000 to $180,000. Add roughly $3,000 to $5,000 in permit, plan review and impact fees, which is an estimate from one source rather than a published fee schedule, so confirm it with your permitting jurisdiction.
How solid are those numbers?: Treat them as planning ranges, not prices. They come from two third-party estimator sites, ADU Zoning and ADU Wizard, both read in full on 2026-08-17, neither of them a government publication. The two land in nearly the same place on total project cost, which is why totals are shown here. They differ by roughly a factor of two on cost per square foot, so a per-square-foot rate is not a reliable way to budget an ADU here and none is quoted.
How fast will someone get back to me?: Your request goes to an independent local ADU builder, usually within about an hour during the day. The builder then contacts you to look at the property and price the project on their own schedule.
What types are covered?: Detached ADUs, attached ADUs, garage conversions and basement junior ADUs. See every type.

Only a builder standing on your lot can price your actual project.

Updated August 2026