Accessory Dwelling Unit (ADU) Construction in Madison, WI — Costs $61,850 to $360,792
What does accessory dwelling unit (adu) construction cost in Madison? Average $154,625, ranging $61,850–$360,792. Labor runs $32.15/hr locally — 3% above the national average. Free breakdown with material + labor split.
Madison, WI Market
+3% vs nationalLabor Rate
$32.15/hr
Material Index
99
Avg Permit Cost
$1,066
Median Home Price
$244,011
Madison is a mid-sized city in Wisconsin with a healthy pool of local contractors. Homeowners generally have several options to compare for a accessory dwelling unit (adu) construction, which helps keep pricing competitive. Costs in Madison run slightly above the national average, though the gap is modest enough that smart material choices and timing can close it. At a median home price of $244,011, homeowners in Madison should weigh the project cost (63.4% of home value) carefully against expected returns to avoid over-improving for the local market.
Low Estimate
$61,850
National: $60,000
Mid-Range
$154,625
National: $150,000
High End
$360,792
National: $350,000
Per Sq Ft
$258
National: $250
Accessory Dwelling Unit (ADU) Construction Cost Calculator for Madison
Adjusted for Madison's labor rate ($32.15/hr) and material costs (index 99).
Mid-grade materials, good quality fixtures, standard options.
Estimated Total in Madison
$154,625
Based on 200 sq ft at mid quality, adjusted for Madison market rates.
Local Cost Breakdown
At Madison's average rate of $32.15/hr (7% above national avg)
Material cost index 99 (1% below national baseline of 100)
Accessory Dwelling Unit (ADU) Construction vs. Home Value in Madison
| Metric | Madison | National Avg |
|---|---|---|
| Accessory Dwelling Unit (ADU) Construction (Mid-Range) | $154,625 | $150,000 |
| Median Home Price | $244,011 | $350,000 |
| Project as % of Home Value | 63.4% | 42.9% |
| Estimated ROI | 80% | 80% |
| Median Household Income | $60,182 | $75,000 |
What Affects the Price in Madison
- 1Local labor rates ($32.15/hr in Madison)
- 2Material cost index (99 vs national 100)
- 3Attached vs detached
- 4Size and bedroom count
- 5Kitchen and bath quality
- 6Local ADU regulations
Popular Upgrades
- Full kitchen
- Separate entrance
- Solar panels for energy independence
Other Projects in Madison, WI
Second Story Addition
$206,167
Room Addition
$92,775
Swimming Pool Installation
$66,473
Garage Addition
$56,696
Home Addition
$82,140
Inground Swimming Pool
$66,208
Attic Conversion
$56,920
Swimming Pool Construction
$51,746
Accessory Dwelling Unit (ADU) Construction in Other Wisconsin Cities
Planning a Accessory Dwelling Unit (ADU) Construction in Madison
Building permits are typically required for a accessory dwelling unit (adu) construction in Madison. The average permit fee in this area is $1,066, though costs vary based on project scope. Permit fees in this market are above average — factor them into your total budget. Plan for 6-18 months from start to finish.
A accessory dwelling unit (adu) construction is a complex project best left to licensed professionals. In Madison, skilled contractors charge an average of $32.15/hr, and the specialized nature of this work means cutting corners on labor can lead to costly rework.
For the median Madison household earning $60,182/year, this project at $154,625 represents a significant investment. Consider financing options or phasing the work to spread costs over time.
Accessory Dwelling Unit (ADU) Construction — National Guide
See the full national cost guide with DIY tips, cost factors, and ROI analysis.
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