Services

Home Additions & ADUs

More space without the move. We build additions and accessory dwelling units that feel like they were always part of the home.

What We Do

Expand Your Footprint

Whether you need a second story, a garage conversion, or a standalone ADU, we handle the full scope — from permits and engineering to framing, finishing, and final walkthrough. One crew, one point of contact, no subcontractor chaos.

ADUs are one of the smartest investments a homeowner can make in the Pacific Northwest. Rental income, space for family, or a private home office — whatever the purpose, we build it to code, on time, and with the kind of communication you actually deserve.

Every addition we build is engineered to match the existing structure. That means matched rooflines, consistent siding, and seamless tie-ins so the new space doesn't look bolted on — it looks like it belongs.

What We Handle

  • Second-story additions
  • Garage conversions
  • Detached ADUs & cottages
  • Room additions & bump-outs
  • Foundation & structural engineering
  • Permit coordination & inspections
  • Insulation & vapor barrier
  • Full interior finishing

Why Bell & Hammer

  • Fully licensed, bonded & insured in Washington
  • All permits pulled and managed by us
  • Daily communication updates
  • Realistic timelines we actually hit
  • Clean job sites, respectful crews
  • No hidden costs or surprise change orders
  • Trusted network of trade partners
  • 24-month workmanship warranty
  • Client Hub portal to track your project
FAQ

Common Questions

Do I need a permit for an ADU?+

Yes — and we handle all permitting and inspections for you. ADUs in Washington have specific zoning and setback requirements that we navigate as part of the project.

How long does a home addition take?+

Depends on scope, but most additions run 3-6 months from permits to completion. We set a realistic timeline upfront and stick to it.

Will the addition match my existing home?+

That's the goal. We match rooflines, siding, and trim so the addition looks like it was always there — not bolted on.

Get Started

Ready to Add On?

Tell us what you're envisioning. We'll follow up within one business day with next steps.