Additions – Signature Build

Love Your Home Again With More Space

Sometimes the house you love just needs a little more breathing room. A cramped kitchen that can’t handle family gatherings. A master bedroom that barely fits your furniture. A home office that’s currently your dining table.

As specialized home addition contractors in the Greater Seattle Area, we help you expand your living space without sacrificing the character that made you choose your home in the first place. Our room additions seamlessly blend with your existing architecture while solving your space problems. We handle everything from initial concept drawings through final inspections, managing permits and timelines so you can focus on planning how you’ll use your new space.

Why Choose Signature Build for Seattle Home Additions & Extensions

Design Integration: Your addition will look like it was always part of your home, not an obvious afterthought.
Structure First: We evaluate your home's foundation and framing to ensure it can properly support your new addition.
Permit Experts: Our team navigates Seattle's complex permitting process, preventing costly delays and revisions.
Livable Construction: We create containment systems that minimize dust and disruption to your living space during the build.

Home Expansion Throughout Seattle's Diverse Neighborhoods

We’ve completed room additions across Seattle’s varied architectural landscape – from Craftsman homes in Wallingford to mid-century modern houses in View Ridge to Victorian treasures in Queen Anne. Each project presents unique challenges, whether matching detailed trim in older homes, working with challenging lot setbacks, or designing additions that maximize natural light in Seattle’s cloudy climate.

Based in Everett, WA, our experience includes second story additions, kitchen expansions, master suite additions, and family room extensions throughout the Seattle area. This breadth of experience means we understand the specific structural and design considerations that make Seattle home additions successful.

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Build, Convert, Expand: Expert Home Services Across the Greater Seattle Area

DADU & ADU

Seattle ADU & DADU Construction

CUSTOM BUILD

Seattle Custom Home Building

CONVERSIONS

Complete Home Conversions

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Financing Your Home Addition

Expanding your Seattle home through a carefully planned addition often delivers better value than moving to a larger house. We partner with lenders who specialize in home improvement financing, offering options from home equity lines to construction loans.

Many clients are surprised to discover how monthly payments for quality home additions compare favorably to Seattle’s rising real estate costs. Our team provides detailed cost breakdowns that help you make informed financial decisions about your project scope.

Frequently Asked Questions about Seattle Home Additions

How much does it cost to add a room to a house in Seattle?

Room addition costs in Seattle typically range from $300-$500 per square foot, depending on the type of space, complexity of design, and current material costs. A basic 400-square-foot family room addition averages $120,000-$200,000, while second story additions generally start around $200,000. Bathroom and kitchen additions fall on the higher end of the price spectrum due to plumbing and electrical requirements.

How long does it take to build a home addition in Seattle?

Most home addition projects in Seattle take 4-7 months from start to finish. Design and permitting typically requires 6-10 weeks, with construction time frames ranging from 3-5 months depending on project size, complexity, and weather conditions. Second story additions and kitchen expansions generally take longer than basic room additions due to their complexity and impact on existing living space.

What permits are needed for a home addition in Seattle?

Seattle home additions require several permits, including building permits, electrical permits, plumbing permits (if applicable), and sometimes mechanical permits. Our team manages the entire permitting process, including preparing required documentation, submitting applications, and coordinating inspections. We also navigate special requirements for homes in historic districts or environmentally critical areas.

Can I add a second story to my Seattle home?

Many Seattle homes can support second story additions, though structural evaluation is essential. We assess your foundation, load-bearing walls, and existing framing to determine feasibility. Even older Seattle homes can often accommodate second floors with appropriate structural reinforcement. Our design team creates second story additions that complement your home’s architectural style while maximizing square footage.

What types of additions work best for Seattle's traditional homes?

Seattle’s Craftsman, Tudor, and Victorian homes require carefully designed additions that respect original architectural details. For these homes, we focus on matching rooflines, window styles, trim details, and siding materials. Our designers create additions that look original to the home while incorporating modern conveniences and energy-efficient features that enhance comfort and functionality.

Seattle Home Remodeling and Additions: Room to Grow Without Moving

All Fixtures, materials, and labor included

Built by a local, vetted contractor

3 Weeks Average Time To Complete

Incorporating Festive Patterns

Textures Into Your Holiday Home Decor