How Much Does It Cost to Build an ADU in Connecticut?
How Much Does It Cost to Build an ADU in Connecticut?
One of the first questions homeowners ask about an accessory dwelling unit is how much it costs. Here is what homeowners in Wolcott, Waterbury, Cheshire, and the surrounding region can expect, including typical price ranges, what drives cost, and how payments are structured.
Typical ADU Cost in Connecticut
Most ADUs in Connecticut cost between $175,000 and $250,000, with many projects landing around $200,000. That range typically covers a turnkey unit of about 650 square feet, from site work and foundation through finished interiors that are ready to move in.
What Affects the Price?
Several factors shape the final cost of your ADU:
- Size: Allowed square footage depends on your lot and existing home.
- Utilities: Properties on city water and sewer usually cost less to connect than properties on a well and septic system.
- Septic capacity: If the health department finds your septic system is not large enough for another dwelling, an upgrade adds cost.
- Finishes: Flooring, cabinets, and fixtures vary in price.
How ADU Payments Work
ADU projects are paid in five to six milestone payments tied to construction progress. On a $200,000 project, the deposit is about $25,000, which covers material orders and permit fees. Additional payments follow as the foundation is completed, framing goes up, mechanicals are installed, exterior siding, roofing, and windows are finished, and interior finishes such as the kitchen, flooring, and paint are complete.
Is Insurance an Option?
Homeowners insurance does not pay to build a new ADU. It is a planned improvement, so most homeowners pay directly or through financing. Before an appointment, our team talks through budget, timeline, and property details so you know what to expect.
Ready to price out an ADU for your property? Contact Bartlett Contracting to start planning, or explore our remodeling services.
Frequently Asked Questions
How much does an ADU cost in Connecticut?
An ADU in Connecticut typically costs between $175,000 and $250,000. Many projects fall near $200,000 for a unit of about 650 square feet. Your final price depends on size, utility connections, site conditions, and finish selections. Properties on city water and sewer generally cost less to connect than properties that rely on a private well and septic system.
How much is the deposit to start building an ADU?
The deposit is typically about $25,000 on a $200,000 ADU project. It covers ordering materials and paying permit fees so the project can move forward. After the deposit, the remaining balance is paid at construction milestones, so each payment lines up with visible progress on your property.
How many payments are made during an ADU build?
Most ADU projects are paid in five to six milestone payments. Payments follow the deposit, the foundation, framing, mechanical installation, exterior finishes like siding, roofing, and windows, and interior finishes like the kitchen, flooring, and paint. Once the final stage is complete, the ADU is turnkey and ready to move in.
Is it cheaper to build an ADU on city water and sewer?
Yes, building an ADU is generally less expensive on city water and sewer. Properties with a private well and septic system may need a health department review to confirm the septic system can support another dwelling. If the system needs to be upgraded, that work adds to the total project cost.
Will homeowners insurance pay for an ADU?
No, homeowners insurance does not pay to build a new ADU. Insurance typically covers damage from covered events, not planned new construction. Most homeowners fund an ADU through savings or financing. Once your ADU is built, talk with your insurance agent about how it should be covered as part of your property.
