Madison, WI & Dane County
ADU Resource Hub — Madison, WI & Dane County
Building an ADU in Madison means navigating 15 different municipal ordinances, permit timelines that vary by city, financing options specific to Wisconsin homeowners, and construction costs shaped by Wisconsin's 48-inch frost depth. This is everything you need — organized in one place. Wisconsin's only ADU-only design-build firm.
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ADU Planning Tools — Madison, WI
Free tools to start evaluating your project before the first conversation.
Free Tool
ADU Cost Calculator
Estimate your ADU cost based on size, type, and finish level. Built on real Dane County project data.
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Free Tool
ADU Zoning Map — Dane County
Interactive map showing ADU zoning status for every municipality in Dane County. Tap any city or village to see current rules.
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Free Consultation
Free Feasibility Check
We review your specific parcel, municipality, and goals. Real answers in one conversation — no commitment required.
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Decision Resources
ADU Cost & Alternative Comparisons
Cost comparisons and decision guides for homeowners evaluating ADUs against the alternatives.
Comparison
ADU vs. Assisted Living — The Cost Comparison
Madison-specific numbers: $5,000–$8,000/month for assisted living vs. a one-time ADU build. Most families break even in 2–3 years.
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Cost Guide
ADU Cost in Madison, WI
Real Dane County line items: frost-depth foundations, Park Impact fees, MGE meter costs, water laterals. Updated 2025.
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Use Case
Multigenerational Living in Madison
How ADUs enable multiple generations to live on one property — with full independence for everyone.
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What People Call Them
Granny Flats, In-Law Suites & Backyard Cottages in Madison, WI
ADUs go by many names. Whatever you call it, Boundless Tiny Homes builds it — permitted, code-compliant, and built for Wisconsin.
Guide
Granny Flat — Madison, WI
What a granny flat is, why people build them in Dane County, and how to get one built legally and correctly.
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Guide
In-Law Suite — Madison, WI
The modern in-law suite is a detached ADU. Why it beats a converted basement, and what it takes to build one right.
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Guide
Backyard Cottage — Madison, WI
Backyard cottages (ADUs) in Madison — what they are, what they cost, and who builds them across Dane County.
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Core Guides
How to Build an ADU in Madison, WI
The fundamentals — what ADUs are, what they cost, how the permit process works, and how to finance them.
Guide
What’s an ADU?
The complete explanation of Accessory Dwelling Units — types, uses, what's allowed in Wisconsin, and how ADUs differ from other housing types.
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Guide
Understanding ADU Pricing
What drives ADU costs in Wisconsin — size, site conditions, finishes, and foundation type. How to read a proposal and avoid surprises.
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Guide
ADU Financing Options
How homeowners finance ADU projects in Wisconsin — HELOCs, construction loans, cash-out refinances, and local programs in Dane County.
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Reference
ADU FAQ
Answers to the most common questions about ADUs in Madison and Dane County — zoning, permits, costs, timelines, and design.
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Guide
Our Build Process
How a Boundless project works from feasibility check through Certificate of Occupancy — five phases, fully managed, no surprises.
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Guide
7 Steps to Build an ADU in Madison
The step-by-step path from initial idea to move-in day — what happens at each phase and what you need to decide.
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Use Cases
Why Madison Homeowners Build ADUs
In-depth guides for the most common reasons to build an ADU in Madison — aging parents, rental income, and accessibility.
Use Case
ADUs for Aging Parents
Keep aging parents close without giving up privacy or paying assisted living costs. The full case for ADUs as a family housing solution.
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Use Case
Accessible Homes & ADUsNew
ADA ADU design in Madison — zero-step entry, curbless showers, grab bar blocking, and packages for every level of accessibility.
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Use Case
ADUs for Rental Income
Build a legal rental unit on your property in Madison. How ADUs pencil out as long-term investments in the Dane County market.
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Zoning & Regulations
ADU Zoning Rules by Municipality — Dane County, Wisconsin
Every municipality in Dane County has its own ADU ordinance. Find yours below — current setbacks, lot size requirements, owner-occupancy rules, and permitting notes.
Madison
Permitted by right
Fitchburg
Permitted by right
Middleton
Permitted by right
Verona
Permitted by right
Sun Prairie
Conditional use
Stoughton
Permitted by right
McFarland
Permitted by right
DeForest
Permitted by right
Waunakee
Permitted by right
Monona
Permitted by right
Cottage Grove
Conditional use
Mount Horeb
Permitted by right
Deerfield
Limited
ADU Zoning Guide — Madison
Current rules + recent changes
All 15 Municipalities →
Full zoning index
Blog — ADU Intelligence
ADU Guides & Local Updates — Madison, WI
Practical guides on permits, financing, design, zoning, and construction — written from real project experience in Dane County.
Permitting & Zoning
What the ADU Permit Process Actually Looks Like in Dane County
The Real Permitting Timeline: Madison vs. Fitchburg vs. Middleton
Madison’s New Zoning Laws Make It Easier to Build ADUs
ADU Zoning Made Simple: Get Your ADU Approved in Madison
ADU vs. Duplex: What’s the Difference in Madison?
Can an HOA Block You From Building an ADU in Madison?
ADU Parking Requirements Across Dane County
What Triggers an Impact Fee on an ADU in Madison?
Financing & Value
Breaking Down the Best ADU Financing Options for Homeowners
How Much Rental Income Can an ADU Generate in Madison?
ADU Rental Income and Taxes: What Madison Landlords Need to Know
Will an ADU Boost Your Property Value?
How an ADU Can Boost Your Property Value in Madison
Can You Sell Your ADU Separately From Your House in Wisconsin?
Can You Airbnb Your ADU in Madison?
Detached vs. Attached ADU at Resale: Which Adds More Value?
Design & Construction
ADU Foundation Options in Wisconsin: Slab, Frost Wall, or FPSF?
Mini-Split vs. Radiant vs. Forced Air: The Right HVAC for a Wisconsin ADU
ADU Insulation and Building Envelope Standards for Wisconsin
ADU vs. Home Addition: Which One Makes More Sense?
The Risks of Pre-Fab ADUs and Tiny Homes
Why Hiring a General Contractor for Your ADU Might Be a Mistake
Tree Removal and ADU Placement: Madison’s Urban Forestry Rules
Designing an ADU for a Parent: The Specific Details That Matter
Ownership & Operations
Shared Utilities vs. Separate Meters: What ADU Owners in Madison Need to Know
How ADUs Affect Your Homeowner’s Insurance
ADU Addresses in Madison: How the 911 Registration Process Works
A Smarter Alternative to Assisted Living: ADUs Keep Your Family Close
Two ADUs, One Property: Madison Landlords Take Note
Two ADUs on One Lot: Madison’s Updated Rules
The Dane County ADU Checklist: Everything Before You Start
Will an ADU Add Square Footage to My House?
Built Work
Case Studies
Real projects in Madison — photos, stats, timelines, and the details that made each one work.
Garage ADU · Vilas Neighborhood
Two-Story Garage ADU — Vilas Neighborhood, Madison
700 sq ft above-garage ADU on a 46×24 ft constrained lot. Certificate of occupancy in 5 months, on budget.
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Single-Story ADU · North Side Madison
Single-Story ADU — North Side, Madison
625 sq ft detached ADU with vaulted ceilings, custom archway, and timber-frame covered patio. CO in 4 months.
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Ready to start your ADU project?
The feasibility check is free. We review your lot, your municipality’s zoning rules, and your goals — then give you a clear picture of what’s buildable and what it costs.
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