Accessory dwelling units adus — Hillsboro, OR
Last updated: September 24, 2026
What affects the price
Building an ADU is a custom project, so costs vary based on your specific choices. Site conditions are the biggest factor; if your land requires significant grading, utility extensions, or foundation work, those expenses add up quickly. Choosing high-end finishes, custom cabinetry, or complex roof lines will also push the budget higher compared to a standard design. Prefabricated units often offer predictable costs, while custom site-built structures allow for more flexibility but can be harder to estimate upfront. Exact pricing confirmed free on the call.
About this service
ADUs are secondary housing units that provide extra space for guests, family, or renters. You should consider an ADU if you want to increase your property value or need more living space without moving. Prices typically vary based on the square footage, the quality of construction, and necessary utility upgrades for your specific lot. Exact pricing confirmed free on the call.
Frequently asked in Hillsboro
What is the cost of building an ADU?
What is required for an ADU permit?
What makes an ADU the 'best' option?
Are there ADU grants available?
While specific ADU grant programs can fluctuate, some governmental or non-profit organizations may offer grants or low-interest loans for accessory dwelling unit construction, particularly those intended for affordable housing. Researching current initiatives through local housing authorities or community development programs is advisable. The pros can sometimes offer guidance on potential funding avenues.
Where can I find 'adu near me' services?
Are ADU regulations the same in Massachusetts?
No, ADU regulations are not uniform across states or even within different cities. Massachusetts has its own distinct set of laws governing accessory dwelling units, which differ significantly from Oregon's statewide ADU policies and Hillsboro's local ordinances. It is crucial to work with ADU professionals who are intimately familiar with the specific requirements of the location where the ADU will be built.
How do I get an ADU quote?
Also serving nearby: Beaverton · Portland · Vancouver · Gresham · Salem
More on this: HUD ADU resources — ADU policy and financing research.
Service area details
Serving all of Hillsboro — population 107,730; about 4,168 residents per square mile across 25.8 sq mi. ZIP codes covered include 97123, 97124, 97129.
Neighborhoods served in Hillsboro: Downtown Hillsboro, Orenco Station, Hawthorn Farm, Brookwood, Walnut Creek, South Hillsboro — and every surrounding area.
Areas we serve
Browse by state, then city.