Need more space without the cost of moving? BB-Builders Pro builds custom home extensions for homeowners across the greater Seattle area.
Whether you need an extra bedroom, a bigger kitchen, or a second story, we design and build home extensions that match your existing home. We serve King, Pierce, and Snohomish Counties. Every project is fully permitted and built to last.
Trusted Family-Owned Contractor
We are licensed, bonded, and insured in Washington State. Our crew has built home extensions across Seattle, Bellevue, Tacoma, and the surrounding area.
Every home extension is designed to blend with your existing structure. We match rooflines, siding, and finishes so the addition looks original.
Your new space connects naturally to the rest of your home. We plan for traffic flow, natural light, and structural continuity from day one.
We pull all permits and manage zoning approval through King, Pierce, and Snohomish County offices. No surprises, no delays from paperwork.
We use durable framing, modern insulation, and energy-efficient windows. Your home extension will hold up to the Pacific Northwest climate for decades.
BB-Builders Pro handles all types of residential home extensions across the greater Seattle area. Here is what we build:
Add a new bedroom, home office, guest room, or in-law suite to the back or side of your home.
Expand upward when you cannot expand outward. We build full and partial second stories on existing single-story homes.
Open up a tight kitchen or dining room. We extend the footprint and redesign the layout for better function and flow.
Create more room for daily life. A family room addition gives you the space your household actually needs.
Add a primary bedroom with a private bath, walk-in closet, and dedicated space away from the rest of the home.
Turn an underused garage into a livable space. Great for rental income, multigenerational living, or a home gym.
Bring the outdoors in. A sunroom or enclosed patio addition adds light-filled living space you can use year-round.
Have something specific in mind? We work with your lot, your style, and your budget to design a custom home extension that fits.
Testimonials
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We come to your home, assess your lot and structure, and discuss your goals. No pressure, no obligation.
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We create detailed plans and 3D models so you can see your home extension before we break ground.
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We file all permits with King, Pierce, or Snohomish County. We handle zoning, structural review, and municipal sign-off.
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Our crew manages foundation work, framing, roofing, and all finish work. We keep the site clean and communicate throughout.
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Before we call a project done, we do a full walkthrough with you and confirm everything passes inspection.
A home extension adds new square footage to your existing house. Common examples include extra bedrooms, kitchen expansions, second-story additions, and sunrooms.
Cost depends on the size, type, and finish level of the extension. A single-room addition typically starts around $80,000 to $150,000. A second-story addition can run higher. We provide a detailed estimate after a free site visit.
Most projects take 3 to 6 months from permit approval to completion. Timeline depends on scope, weather, and permit processing times in your county.
Yes. Any structural addition requires a building permit. We handle the full permit process for homeowners in King, Pierce, and Snohomish Counties.
In most cases, yes. We plan construction phases to minimize disruption to your daily routine.
Yes. Adding livable square footage is one of the most effective ways to increase resale value in the Seattle market.
Your lot size, setback requirements, budget, and how the addition connects to your existing layout. We walk through all of this during the consultation.
Look for a licensed Washington State contractor with verified local projects, pulled permits, and clear communication. BB-Builders Pro checks all three.
Options include home equity loans, construction loans, and our in-house financing program. See details in the financing section below.
Simple Financing Options
Discover the perfect financing solution for your remodeling project. We provide tailored options to suit your budget and ensure your dream home becomes a reality.
Start with a free consultation. Tell us about your project and we will get back to you fast.
We serve homeowners across King, Pierce, and Snohomish Counties. Call us or fill out the form to get your free estimate today.