Expand and Utilize Space: Washington ADU Contractors

There are many reasons to invest in an ADU (Accessory Dwelling Unit). Many find that these spaces are a smart way to expand their living space, create room for their aging parents, host guests, or make additional income. However, undertaking an ADU project on your own can be extremely overwhelming and complicated.

The experts at Capitol Custom Construction have the local code knowledge (including Washington State’s HB 1337 ADU mandates), construction ability, and attention to detail required for a successful ADU build. Looking specifically for Tumwater permitting details? Visit our dedicated ADU Builder in Tumwater, WA guide.

Permitting Handled End-to-End: We are knowledgeable about the complicated processes for obtaining the right permits to start work. We take care of the red tape so you don’t have to worry about it.
Property Value & Income: ADUs increase property value and, in many cases, serve as additional income for families and homeowners. Building an ADU is a smart way to provide financial security.
Detached, Attached & Garage Conversions: Depending on your property type, we assist with garage or basement conversions, stand-alone units, and attached units. We consult with you to find the best ADU fit for your property and life circumstances.

Functional, Modern, and Quality ADU Builders

We take you through the ADU building process from start to finish, leaving you with no unanswered questions or in the dark about your ADU project. We thoroughly explain every process, from permitting, code, and construction to completion.

Lot Feasibility & Zoning Audit: Setback verification, lot coverage limits, water table check, and sewer vs. LOTT/septic evaluation.
Custom ADU Design & Engineering: Full architectural and structural plans tailored to your parcel.
Turnkey Utility & Site Construction: Trenching and foundation, framing, roofing, siding, electrical, plumbing, drywall, countertops, and final occupancy inspection.

Why Homeowners Partner With Capitol Custom Construction

Professional Contractors: Entrust your next project to contractors who have been in the game for years and have the know-how to execute your dream build.
Licensed and Insured: Our contractors are licensed and insured experts. Our work is done at the highest safety standards.
We Fill Any Need: Our services range from new home construction to general home projects. Whatever your build is, we can do it.
Honest and Trustworthy: No surprise work, fees, or flaky contractors here. We communicate clearly and deliver what we promise.

Cory and Betianne Vaughn, Owners of Capitol Custom Construction

Cory & Betianne Vaughn

Owners, Capitol Custom Construction — Olympia Master Builders

We are upfront, straightforward, and defined by a straight-to-the-point operational methodology. We pride ourselves on clear, insight-driven communication and prompt execution. We do what we say and honor our commitments.

Coastal home decking by Capitol Custom Construction

Coastal Vacation Home Client

Three-Time Return Client — Washington Coast

Capitol Custom Construction built our coastal vacation house decking using WOLF composite boards, a Fortress Aluminum picket handrail system, and all marine-grade stainless steel fasteners engineered for coastal weather.

Powell Barn Custom Build by Capitol Custom Construction

Custom Home & Barn Build Client

South Sound Custom Build — Thurston County, WA

From initial excavation and foundation work through structural framing, custom drywall, bathroom tilework, and exterior roofing and siding, Capitol Custom Construction delivered radical transparency and zero surprises.

Accessory Dwelling Units

Expand and Utilize Space: Washington ADU Contractors

Functional, Modern, and Quality ADU Builders

Why Homeowners Partner With Capitol Custom Construction

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More of Our Services

Capitol Custom Construction Pushes the Boundaries of What Is Possible in Your Home Build or Renovation.