Accessory Dwelling Unit (ADU) Construction in Renton, WA — Costs $81,880 to $477,633
What does accessory dwelling unit (adu) construction cost in Renton? Average $204,700, ranging $81,880–$477,633. Labor runs $44.98/hr locally — 36% above the national average. Free breakdown with material + labor split.
Renton, WA Market
+36% vs nationalLabor Rate
$44.98/hr
Material Index
123
Avg Permit Cost
$1,646
Median Home Price
$560,000
Renton is a mid-sized city in Washington 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. At 36% above the national average, Renton is one of the more expensive markets for home improvement — driven primarily by above-average labor rates in the region. With a median home price of $560,000, this accessory dwelling unit (adu) construction represents just 36.6% of typical home value — a relatively small investment that can significantly boost curb appeal or functionality.
Low Estimate
$81,880
National: $60,000
Mid-Range
$204,700
National: $150,000
High End
$477,633
National: $350,000
Per Sq Ft
$341
National: $250
Accessory Dwelling Unit (ADU) Construction Cost Calculator for Renton
Adjusted for Renton's labor rate ($44.98/hr) and material costs (index 123).
Mid-grade materials, good quality fixtures, standard options.
Estimated Total in Renton
$204,700
Based on 200 sq ft at mid quality, adjusted for Renton market rates.
Local Cost Breakdown
At Renton's average rate of $44.98/hr (50% above national avg)
Material cost index 123 (23% above national baseline of 100)
Accessory Dwelling Unit (ADU) Construction vs. Home Value in Renton
| Metric | Renton | National Avg |
|---|---|---|
| Accessory Dwelling Unit (ADU) Construction (Mid-Range) | $204,700 | $150,000 |
| Median Home Price | $560,000 | $350,000 |
| Project as % of Home Value | 36.6% | 42.9% |
| Estimated ROI | 80% | 80% |
| Median Household Income | $68,000 | $75,000 |
What Affects the Price in Renton
- 1Local labor rates ($44.98/hr in Renton)
- 2Material cost index (123 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 Renton, WA
Second Story Addition
$272,933
Room Addition
$122,820
Swimming Pool Installation
$86,953
Garage Addition
$75,057
Home Addition
$108,096
Inground Swimming Pool
$86,077
Attic Conversion
$75,797
Swimming Pool Construction
$68,907
Accessory Dwelling Unit (ADU) Construction in Other Washington Cities
Planning a Accessory Dwelling Unit (ADU) Construction in Renton
Building permits are typically required for a accessory dwelling unit (adu) construction in Renton. The average permit fee in this area is $1,646, 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 Renton, skilled contractors charge an average of $44.98/hr, and the specialized nature of this work means cutting corners on labor can lead to costly rework.
For the median Renton household earning $68,000/year, this project at $204,700 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.
All Construction Costs in Renton
View labor rates, material costs, and project estimates for Renton, WA.
Explore All Project Cost Guides
Compare costs across 120+ home improvement projects in 3,636 cities nationwide.
View All Project Costs