Why Bay Area Homeowners Choose Design-Build for Additions
Design-build gives you one point of contact, faster timelines and cost control. The design-build approach brings design and build teams together under one roof, so…
When your home needs more space, Mares & Dow Construction & Skylights delivers custom home additions that blend seamlessly with your existing structure. From additional bedrooms to full second-story expansions, our design-build team ensures every project enhances your home’s comfort, functionality, and long-term value. With over 40 years of experience in the Bay Area, we combine expert craftsmanship, thoughtful design, and quality materials to create additions that feel like they were always part of your home.
Home additions are more than just extra square footage—they’re an investment in your lifestyle and the future of your property. Whether you’re looking to accommodate a growing family, create a home office, or add luxurious living space, our team works closely with you to transform your vision into a practical, beautiful, and enduring addition.
Adding onto your home requires careful planning, precise construction, and attention to every architectural detail. Our team handles the entire process, from conceptual design and permitting to construction and finishing touches, ensuring a seamless experience and superior results. We specialize in additions that include:
Every addition is fully customized to meet your lifestyle needs, budget, and design preferences while maintaining architectural harmony with your home.
Seamless Integration With Your Existing Home
A well-executed addition should feel like it was always part of your home. Mares & Dow Construction & Skylights carefully matches materials, finishes, roofing, and architectural details, so your new space blends naturally with your existing structure. Our goal is to make your home bigger, more functional, and more beautiful—without ever looking “added on.”
Contact Mares & Dow Construction & Skylights today and let our 40 years of Bay Area expertise turn your dream project into reality.
Mares & Dow Construction & Skylights is certified and accredited by the best manufacturers in the industry. From Grip-Tite Foundation Systems, to James Hardie Siding, to VELUX Skylights, you can be sure to get the highest quality products for whatever your project.
Serving the San Francisco Bay Area for over 40 years with quality general contracting, home remodeling, and skylight installation means you'll get the benefits of our expertise for every project.
Maintaining a high level of customer satisfaction, we are proud to have provided our customers throughout the San Francisco Bay Area with quality construction and home improvement services for 40 years. With half of our new clients coming to us from referrals, it’s no secret that our customers/friends are truly pleased with the work we do.
Mares & Dow Construction & Skylights, Inc. is a longstanding partnership of 40 years between Archie Mares, Dennis Dow and hundreds of great customers throughout the San Francisco Bay Area. We are a general contractor, building custom homes, additions, home remodeling, skylights, retaining wall construction and commercial remodeling.
Maintaining a high level of customer satisfaction, we are proud to have provided our customers throughout the San Francisco Bay Area with quality construction and home improvement services for 40 years. With half of our new clients coming to us from referrals, it’s no secret that our customers/friends are truly pleased with the work we do.
Quality and service come first. We approach every job, big or small, with the same care and attention to detail we’d give our own homes. Our team combines time-tested building practices with modern innovation to deliver results that stand the test of time.
Ready to start your next project? Whether you’re planning a home remodel, skylight installation, or foundation repair, our team is here to help.
Reach out to us for a free consultation. We’ll listen, offer expert guidance, and provide a detailed estimate tailored to your goals.
To enhance the lives of Bay Area homeowners through expert construction, thoughtful design, and dependable service. For over 40 years, our mission has remained simple: build with integrity, serve with pride, and create spaces our clients love to live in.
We believe in integrity, craftsmanship, and lasting relationships. Every project is built on honesty, transparency, and respect - for our clients, our partners, and the homes we’re entrusted to improve.
Mares & Dow Construction & Skylights installed a large Velux skylight for me in August 2017. The entire experience was wonderful and the skylight is beautiful, both functionally and aesthetically. Janet made sure the work was scheduled to be completed before a trip I had planned. Jimmy measured carefully when he quoted the work and even accommodated a last minute change on the location when he arrived to do the work. They protected my new floors and were careful to keep dust to a minimum. Archie came by to ensure that all was going smoothly. Freddy helped matched the stain on my nearly 70 year old tongue and grove ceiling that really took some effort and he even matched some a few small spots that a previous contractor had sanded and removed the original stain. EVERYONE was cheerful and knowledgeable. Now, my little mid century house has emerged into the light!
Mares & Dow Construction & Skylights replaced two aging skylights in our bedroom and installed automatic blinds on four skylights. This was not an easy job, since our bedroom has very very high cathedral ceilings. In fact, one other skylight installer refused to do the job altogether, and a second made a bid that was almost twice as expensive as Mares & Dow Construction & Skylights. Janet Mares, who was our main contact for the job, was a pleasure to work with. Her son, Jimmy, who led the installation, was fearless climbing the ceiling, and he eally knew his stuff. We’re thrilled with our new and improved skylights, and we appreciate Mares & Dow Construction & Skylights’ solid, reasonably priced, work. Thanks guys!
I’ve had Mares & Dow Construction & Skylights install 3 sun tunnels in my home and most recently, 2 skylights in my garage/art studio. I couldn’t be more satisfied with the quality of their work and professionalism! All my communications with their office and installers have been extremely pleasant. I would use them again (and again) and highly recommend them to anyone looking to install Velux skylights/sun tunnels in their home!
Being a new homeowner, i really did my research before having someone come out and give me a quote on a skylight. You never know what to believe when you read yelp reviews. So, i went ahead and had Jimmy from mares and dow come out and give me an estimate. He was right on time, came out and measured and was very professional while he was here. Janet called me a few days later and sent me over an estimate. I went them them and couldn’t be happier. It arrived in the time frame she had told me, and they were out that week. The workers came out on time, and were very friendly and professional. Dennis ( one of the owners) came out as well and checked on the job. The went above and beyond with their work. The skylight looks beautiful! Night and day from the old one. If you are wanting a skylight, i strongly reccomend going with mare and dow
We had Mares & Dow Construction & Skylights install a Velux skylight in our new master bathroom. The space was small and dark, so Mares & Dow Construction & Skylights suggested a big skylight to add in lots of natural light. They built in a double crown molding to beautifully frame the skylight, and now the space is open and airy with wonderful natural light. We can open the skylight during warm months to let in fresh air. It was a superb addition to our bathroom renovation and a great suggestion from Mares & Dow Construction & Skylights. They did a fantastic job and were great to work with! Thanks guys!
Design-build gives you one point of contact, faster timelines and cost control. The design-build approach brings design and build teams together under one roof, so…
Design-build gives you one point of contact, faster timelines, and cost control. The design-build approach brings design and build teams together under one roof, so…
Historic home additions are about preserving the character of an old home while expanding it. To maintain the character, most owners duplicate the existing work.…
In most cases, yes. Mares & Dow Construction & Skylights plans construction zones and workflows to minimize disruption to your daily life. We carefully isolate work areas, maintain safety barriers, and coordinate schedules to limit noise and dust. For larger additions—like second-story expansions or extensive structural projects—some temporary adjustments may be necessary, such as restricted access to certain rooms. We always communicate clearly so homeowners can plan accordingly and stay comfortable throughout the project.
The cost of a home addition depends on the size, scope, materials, finishes, and complexity of the design. A small room extension may be more budget-friendly, while a second-story addition with custom features can represent a larger investment. At Mares & Dow Construction & Skylights, we provide a thorough, detailed estimate after an on-site evaluation of your home. This estimate includes material costs, labor, design, permitting, and project management, so you have a clear understanding of the total investment before construction begins.
Yes. We provide a fully integrated design-build approach, combining architecture, engineering, and construction expertise. Our team works with you to create layouts, floor plans, and structural drawings that reflect your vision, lifestyle, and budget. We offer guidance on materials, finishes, lighting, and space planning to optimize function and aesthetics. This collaborative approach ensures your addition is thoughtfully designed, structurally sound, and beautifully executed from start to finish.
Yes. A well-planned home addition not only increases your living space but also enhances your home’s market value, functionality, and curb appeal. Expanding bedrooms, adding bathrooms, creating in-law suites, or building a larger kitchen or living area can make your home more attractive to future buyers while improving your everyday comfort. At Mares & Dow Construction & Skylights, we focus on quality craftsmanship, attention to detail, and functional design so your addition delivers long-term value while enhancing the enjoyment of your home today.
Mares & Dow Construction & Skylights Inc. proudly provides professional home addition services throughout the major cities of Contra Costa County, including:
Walnut Creek, CA – Home addition contractor specializing in seamless room expansions and custom designs.
Concord, CA – Home addition contractor delivering functional layouts, structural integrity, and expert craftsmanship.
Richmond, CA – Home addition contractor offering full-service home expansions from planning to completion.
San Ramon, CA – Home addition contractor focused on high-quality additions that enhance comfort and property value.
Danville, CA – Home addition contractor providing tailored additions designed to match existing architecture.
Pleasant Hill, CA – Home addition contractor known for reliable service and smooth project execution.
Pittsburg, CA – Home addition contractor handling everything from small room additions to major expansions.
Antioch, CA – Home addition contractor offering cost-effective solutions without sacrificing quality.
Martinez, CA – Home addition contractor experienced in modern, traditional, and multi-room additions.
Brentwood, CA – Home addition contractor creating spacious, well-integrated additions built to last.
Oakley, CA – Home addition contractor delivering practical expansions tailored to everyday living.
Lafayette, CA – Home addition contractor specializing in high-end custom home additions.
Clayton, CA – Home addition contractor providing personalized additions with careful planning and attention to detail.
If you’re located elsewhere in Contra Costa County, contact us to confirm availability and discuss your home addition project.