Do Additions and ADUs Need Permits?

Yes, without question. A home addition or ADU is among the most permit-intensive projects a homeowner can undertake, because you are adding new structure to your property. These projects involve not only building permits but also zoning and land-use considerations that a simple interior remodel does not.

Beyond the structural, plumbing, and electrical permits common to major remodels, additions and ADUs bring in considerations like setbacks (how close to your property lines you can build), lot coverage (how much of your lot can be occupied by structures), and height limits. These rules vary by city and by zoning, and they directly shape what you can build and where. Getting them right at the design stage is essential, because a design that violates them will not be approved.

ADUs in particular have their own set of regulations that have evolved in recent years, covering size, placement, parking, and use. Rules differ across the Eastside's jurisdictions, so what is permitted for an ADU in one city may differ in another. This is an area where working with a builder who knows the local landscape genuinely matters.

The reassuring part is that we handle all of this for you. From the earliest design stage, we account for setbacks, lot coverage, height limits, and zoning, so your addition or ADU is designed to be approvable from the start. We then manage the full permitting process, including any structural engineering, and coordinate inspections through construction. You can read about how permitting varies across Eastside cities.

Because additions and ADUs involve more permitting and engineering, they also have longer timelines, which we build realistically into your schedule. You can read about how long a home addition takes. And if you are weighing an addition against reworking existing space, our guide on whether to remodel or build an addition may help.

To plan a properly permitted addition or ADU, contact us at (425) 405-0147 or request an estimate, and see completed projects in our portfolio.