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.
Renton Home Addition and ADU Construction Specialists
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 Renton 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 Renton: With over a decade serving Renton 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 Renton: 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
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Complimentary Estimate and Expert Guidance from experienced Professionals.
Other Services in your Area
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 Renton Home Additions and ADUs?
Licensed and Insured Renton Contractor
We are fully licensed and insured to perform home additions and ADUs in Renton, ensuring that every project meets state codes and delivers lasting structural integrity.Knowledge of Renton’s Housing Layouts
Renton’s mix of suburban neighborhoods and hillside properties calls for tailored building approaches. We adapt designs to lot sizes, views, and existing architecture for the best results.Practical and Comfortable Spaces
Our work includes in-law suites, garage conversions, and expanded living rooms that improve both the usability and comfort of your home.Durability in Every Detail
We use proven construction techniques, including reinforced framing, moisture protection systems, and premium finishes to ensure your addition stands the test of time.Over a Decade Serving Renton
Since 2011, we have worked in neighborhoods throughout Renton, delivering results that reflect both local character and high construction standards.
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Achieve Your Dream Home With Our Process
Simplified Renton 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 Renton 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.
Renton’s ADU regulations include:
- Size: ADUs must not exceed 1,000 sq. ft. or 40% of the principal dwelling’s floor area.
- Parking: One additional parking space is required.
- Compliance: Must meet all relevant building codes and zoning regulations.
More details can be found on the Renton City Government website.
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!