The cost of building a DADU (Detached Dwelling Unit) in Seattle or Bellevue, much like in other urban areas, varies depending on several factors, including location, size, design, materials, and current market conditions. Here’s a general overview:
Cost Per Square Foot
Basic DADU: For a simple, basic DADU with standard materials and finishes, costs typically range from $220 to $350 per square foot.
Mid-Range DADU: For a DADU with higher-end finishes and custom features, the cost generally falls between $400 to $500 per square foot.
High-End DADU: For a luxury DADU with top-tier materials, custom designs, and features like sustainable building practices, costs can exceed $500 per square foot.
2. Total Cost Estimate
Small DADU (300-500 sq. ft.): $75,000 to $200,000
Medium DADU (500-800 sq. ft.): $150,000 to $450,000
Large DADU (800-1,000 sq. ft.): $200,000 to $500,000+
3. Possible Additional Costs
Permits and Fees:
Permit costs for a DADU in Seattle and Bellevue can range from $4,000 to $10,000, depending on the project's complexity. This includes fees for building permits, design review, and utility connections.
Site Preparation:
Site preparation costs can vary significantly. If your lot requires grading, tree removal, or other prep work, expect to pay between $5,000 and $50,000 or more.
Utility Connections:
Hooking up a DADU to existing utilities (water, sewer, electrical) can add another $10,000 to $30,000, depending on the proximity of connections and any necessary upgrades.
Architectural and Design Fees: Hiring an architect to design your DADU typically costs between 5% to 15% of the total construction budget.
Landscaping and Exterior Work: Don't forget to budget for landscaping around the DADU, which can add $2,000 to $25,000 depending on the scope of the work.
4. Time Frame
Building a DADU typically takes 6 to 12 months, from initial design and permitting to final construction. The timeline can be affected by factors such as permitting delays, weather, and contractor availability.
5. Regulations and Incentives
Both Seattle and Bellevue have specific zoning laws and regulations governing the construction of DADUs. In Seattle, the city has relaxed some zoning restrictions to encourage the building of DADUs as part of its efforts to increase housing density. Bellevue also allows DADUs, but requirements may differ. It’s important to consult local regulations to ensure your project complies with zoning laws.
There are also potential incentives for building DADUs, such as property tax exemptions or reduced permitting fees, depending on the location and whether the unit is used for affordable housing.
6. Financing Options
Financing a DADU can be done through various methods, including home equity loans, construction loans, or cash-out refinancing. Some homeowners also explore financing through rental income generated by the DADU once it's completed.ConclusionBuilding a DADU in Seattle or Bellevue is a great way to add value to your property and create flexible living space. However, the costs can vary widely depending on the size, design, and site conditions. It's essential to budget carefully and work with professionals who are experienced in DADU construction to ensure your project is successful and complies with local regulations.