With over a decade of experience, we design and build ADUs and custom home additions that expand your living space, add value, and blend seamlessly with your home’s style.
Seattle Eastside Home Addition and ADU Building Professionals
Professional Builder
- Licensed & Insured Local Contractor
- Expertise in Permits & Zoning
- Fixtures, Materials & Labor Included
- Custom Home Addition & ADU, DADU Solutions
- Quality Materials & Sustainable Practices
- Reliable, Experienced Craftsmanship
- Full Design & Project Planning
5 Star Rated Seattle Construction Company
14
Years of
Experience
+150
Completed
Projects
FREE QUOTE FOR YOUR ADDITION OR ADU
Professional Addition & ADU Contractor
Seattle’s Eastside, WA
Our Comprehensive Addition & ADU Services Include
ADU Builder in Seattle: With over a decade serving Seattle homeowners, we bring proven craftsmanship to every Accessory Dwelling Unit project. From solid structural work to precise finishes, our team builds attached and detached ADUs designed for durability, comfort, and lasting value.
Home Additions in Seattle: We specialize in high-quality home additions that meet practical needs while upholding our standards for fine construction. Whether you need extra bedrooms, a functional home office, or a dedicated in-law suite, our local knowledge and hands-on approach ensure a result you’ll appreciate for years.
- Garage Conversions
- Sunrooms
- In-law Suites
- Guest Suites
- Home Offices
- Basement Conversions
- Second Story Additions
- Kitchen Extensions
- Bathroom Additions
- Detached ADUs
- Attached ADUs
- Energy-Efficient Upgrades
Let's Talk About Your Remodeling Project
Complimentary Estimate and Expert Guidance from experienced Professionals.
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Our ADU and Addition Services
Attached ADUs
Connected to the main house for multi-gen living or rental income. Designed for a seamless tie-in and code compliance.
- Directly attached to home
- Shared Wall Structures
- Integrated Utilities
- Space-Efficient Layouts
Detached ADUs
Stand-alone backyard cottages for guests or rental. Built for privacy, durability, and local zoning compliance.
- Stand-Alone Structures
- Private Entrances
- Independent Utilities
- Flexible Use Options
Home Additions
Increase square footage with custom additions that match your home’s style and boost long-term value.
- New Bedrooms
- Home Offices
- In-Law Suites
- Seamless Integration
Home Extensions
Targeted expansions: kitchen, bathrooms, living, or sunroom planned for comfort, light, and energy efficiency.
- Enlarged Kitchens
- Spacious Living Rooms
- Added Sunrooms
- Seamless Integration
Why Choose BLC Remodeling LLC for Your Seattle Home Additions and ADUs?
Licensed and Insured Seattle Contractor
We are fully licensed and insured to handle home additions and ADUs throughout Seattle, meeting both Washington State requirements and the city’s specific building standards.Experienced with Seattle’s Diverse Housing Styles
From historic Craftsman homes to modern townhouses, we adapt designs to suit each property’s character and the requirements of its neighborhood.Functional Spaces for Urban Living
We have built basement ADUs, rooftop additions, and compact extensions designed to maximize every square foot in Seattle’s dense housing market.Quality Construction for Lasting Performance
Our work includes reinforced framing, moisture protection systems, and precision finish work to ensure both durability and refined appearance.Over a Decade Serving Seattle Homeowners
Since 2011, we have completed projects across Seattle neighborhoods including Ballard, Capitol Hill, and West Seattle, delivering results that combine structural strength with aesthetic appeal.
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Achieve Your Dream Home With Our Process
Simplified Seattle Home Extension Process
1.
Schedule a Consultation
2.
In-Home Assessment
3.
Receive a Detailed Quote
4.
Schedule and Begin Work
Start Your Home Transformation Today
Schedule Your Seattle ADU or Addition Estimate
Call us anytime, we strive to answer all inquiries within 24 hours.
The project was actually delivered ahead of the contract schedule, which was a pleasant surprise. They work with licensed plumbers, electricians, and mechanical contractors, and they also handled all the necessary permits. Both the rough-in and final inspections passed on the first attempt.
The team not only did the main remodel but also helped with a lot of small extra tasks around the edges. They were very patient in adjusting cabinet alignments and doing touch-ups until everything looked perfect.
We especially appreciated their clear and timely communication. Any changes we requested were discussed and confirmed right away—for example, after the rough-in, we decided to add a vent hood duct, and they adjusted the plan smoothly without delaying the schedule.
Overall, the workmanship, professionalism, and customer service were excellent. We highly recommend BLC remodeling to anyone looking for a reliable and detail-oriented remodeling company.
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Frequently asked questions
Adding an addition to your existing home is generally more cost-effective than building a new house. Home additions make use of existing infrastructure and utilities, which can significantly reduce costs. However, the total expense will depend on the size and complexity of the addition, as well as the materials used.
The cheapest type of home addition is typically a single-room extension, such as a sunroom or a small bedroom. These additions require less structural work and fewer materials compared to multi-room additions or second-story expansions. Costs can be further minimized by choosing cost-effective materials and designs.
The timeline for home additions varies depending on the project’s scope and complexity. On average, a small addition like a single room can take 3-4 months, while larger projects, such as adding a second story, can take 6-9 months. Detailed planning and efficient project management are crucial to staying on schedule.
Seattle’s requirements for ADUs include:
- Size: ADUs can be up to 1,000 sq. ft. or 40% of the main dwelling’s floor area.
- Parking: No additional parking is required if within a half-mile of frequent transit service; otherwise, one parking space is required.
- Compliance: Must adhere to all applicable building codes and zoning regulations.
Visit the Seattle City Government website for more information.
Service Areas
Other Service Areas
Don’t see your neighborhood listed? No problem! We are eager to hear about your project. Call us today, and let’s discuss how we can help. Proudly serving homeowners throughout Eastside and Greater Seattle!