Serving Seattle, Bellevue, Kirkland & the Eastside
Building Your Vision From the Ground Up
Full-service general contractor specializing in custom homes, additions, and major renovations. Transparent process, expert coordination, quality results.
Schedule ConsultationOur Work
Every project represents a family's trust in our team. Here are some of the homes we've built and transformed.
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Modern Craftsman
Kirkland
3,400 sq ft new construction with ADU, featuring open concept living and high-end finishes throughout.
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Great Room Addition
Bellevue
800 sq ft living space expansion seamlessly integrated with the original 1960s home.
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Seattle DADU
Wallingford
750 sq ft detached accessory dwelling unit designed for rental income.
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Mid-Century Renovation
Mercer Island
Complete systems upgrade and open concept conversion while preserving original character.
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Waterfront Custom
Medina
4,200 sq ft lakefront new construction with panoramic views and custom millwork.
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Second Story Addition
Capitol Hill
1,200 sq ft added level with master suite, maintaining the home's craftsman aesthetic.
How We Work
A clear, predictable process from first meeting to final walkthrough. No surprises, no confusion.
Discovery
We learn about your vision, needs, timeline, and budget.
Design
Our team or your architect develops detailed plans and specifications.
Proposal
You receive a comprehensive proposal with clear pricing and timeline.
Build
Construction begins with weekly updates and a dedicated project manager.
Walkthrough
We complete a detailed inspection and hand over the keys.
Discovery
We learn about your vision, needs, timeline, and budget.
Design
Our team or your architect develops detailed plans and specifications.
Proposal
You receive a comprehensive proposal with clear pricing and timeline.
Build
Construction begins with weekly updates and a dedicated project manager.
Walkthrough
We complete a detailed inspection and hand over the keys.
Our Services
From new construction to major renovations, Cornerstone Builders manages projects of every scale. One point of contact, full accountability, exceptional results.
Who We Are
Cornerstone Builders NW is a full-service general contractor specializing in custom homes, additions, and major renovations throughout Seattle and the Eastside. Since 2012, we've helped homeowners bring their visions to life—from initial concept through final walkthrough.
We believe great construction starts with great communication. That's why every project gets a dedicated project manager, weekly updates, and a transparent process from day one. No surprises, no scope creep without your approval, no wondering what's happening on your job site.
Our network of vetted subcontractors has been built over years of working together. When you hire Cornerstone, you get the benefit of established relationships with the best electricians, plumbers, and craftsmen in the region.
Licensed & Insured
Full protection
12+ Years
Building in Seattle
[Client photo: truck, team, or job site]
What Sets Us Apart
We're not just builders—we're project managers who understand that communication matters as much as craftsmanship.
Transparent Process
From initial consultation to final walkthrough, you'll always know what's happening and what's next. Weekly updates, clear timelines, and no surprises on your project.
Vetted Subcontractor Network
Our relationships with the region's best tradespeople have been built over a decade. When we bring someone to your project, we trust them completely—and so can you.
What Our Clients Say
Building a home is a significant investment. Hear from families who trusted Cornerstone with their vision.
“We interviewed five contractors for our home addition. Cornerstone was the only one who walked us through their entire process before we even talked about money. That attention to detail showed up every day of our project.”
Jennifer & Mark W.
Bellevue
Let's Discuss Your Project
Whether you're dreaming of a custom home, planning an addition, or ready to renovate—we'd love to hear about your vision. Free consultations, no pressure.
(555) 555-5555Call for a consultation • Mon-Fri 8am-5pm