Detached accessory dwelling unit — Madison, WI
Last updated: September 24, 2026
What affects the price
Building an ADU is a major project, and the final bill depends on a few key things. Site prep is a big factor; if your land is sloped or needs extensive utility connections, costs go up. The materials you choose—from siding to kitchen finishes—also change the math significantly. Whether you’re building a detached unit or converting an existing garage shifts the permit requirements and structural work needed. We provide exact pricing confirmed free on the call.
About this service
A detached ADU is a standalone building separate from your main home, like a backyard cottage. These provide the most privacy for you or your tenants since there are no shared walls. You need this if you have a large enough yard to accommodate a separate structure.
Frequently asked in Madison
What does accessory dwelling unit mean in Madison?
In Madison, an accessory dwelling unit (ADU) is defined as a secondary, independent living space on a single-family residential lot. It must have its own kitchen, bathroom, and sleeping area. ADUs can be attached to the main house or be a separate structure, such as a backyard cottage, and must adhere to Madison's zoning laws.
Where can I find an accessory dwelling unit builder in Madison?
What is an accessory dwelling unit (ADU) in Madison?
An accessory dwelling unit (ADU) in Madison is a secondary housing unit on a single-family lot that provides independent living facilities. This includes a kitchen, bathroom, and sleeping area. ADUs can be attached to the main dwelling or be a detached structure, like a backyard guest house, and must meet all city regulations.
What are the ADU services available in Madison?
How much does it cost to build an accessory dwelling unit in Madison?
Are there accessory dwelling unit builders near me in Madison?
What is an affordable accessory dwelling unit in Madison?
Also serving nearby: Rockford · Milwaukee · Kenosha · Elgin · Waukegan
More on this: HUD ADU resources — ADU policy and financing research.
Service area details
Serving all of Madison — population 280,305; about 3,373 residents per square mile across 83.1 sq mi. ZIP codes covered include 53701, 53702, 53703, 53704, 53705, 53706, 53707, 53708.
Neighborhoods served in Madison: University Heights, Shorewood Hills, Maple Bluff, Nakoma, Broomfield — and every surrounding area.
More services in Madison
Everything else we cover here.
24 hour adu · accessory dwelling unit · accessory dwelling unit builders · accessory dwelling unit builders near me · accessory dwelling unit companies · accessory dwelling unit construction · accessory dwelling unit construction cost · accessory dwelling unit contractor · accessory dwelling unit contractor san diego · accessory dwelling unit cost · accessory dwelling unit financing · accessory dwelling unit for rent · accessory dwelling unit grants · accessory dwelling unit homes · accessory dwelling unit massachusetts · accessory dwelling unit near me · accessory dwelling unit new hampshire · accessory dwelling unit permit · accessory dwelling unit permit cost · accessory dwelling unit rental · accessory dwelling unit services · accessory dwelling units adus · adu builder · adu building · adu company · adu construction · adu cost · adu estimate · adu housing · adu near me · adu permit · adu quote · adu services · adu unit · affordable accessory dwelling unit · affordable adu · backyard accessory dwelling unit · best accessory dwelling unit · best adu · cost of accessory dwelling unit · cost to build accessory dwelling unit · emergency adu · homes with in law suites · homes with mother in law suites · local adu · modular accessory dwelling unit · prefab adu · prefabricated accessory dwelling unit · what does accessory dwelling unit mean
Areas we serve
Browse by state, then city.