A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateTrusted Home Addition Contractor for Houston Homeowners
Adding square footage to your Houston home means inviting a construction crew into your daily life for weeks or months. You deserve to know exactly who those people are before they ever set foot on your property. Sutton ADU Houston has built home additions across the Houston area since 2006 under the Threshold Standard, which means every technician who arrives at your door is background-checked, identity-verified, uniformed, and photo-badged. Their name and photo are sent to you before the visit. If you’re pricing a detached ADU, garage conversion, or room addition right now, call (940) 242-3207 for a written estimate with the price locked in before any work begins.
Most Houston homeowners we talk to have the same three questions: what will this cost, how long will it take, and who exactly will be in my home. We answer all three in writing. A typical home addition project in Houston runs $165,000 to $340,000 depending on square footage, foundation work, and finish level. Detached ADUs in the 600 to 900 square foot range generally run $180,000 to $320,000 before site work. And every project carries a 365-Day Done Right Promise. If the work isn’t right within a full calendar year, we make it right. That’s not a verbal assurance. It’s stamped on your project documents.
Sunroom Addition
A Sunroom Addition extends your living space with a glass-walled room that brings in Houston’s natural light while keeping out the heat and humidity. Most Houston homeowners add sunrooms when they want extra space for morning coffee, houseplants, or a reading nook without the full cost of a traditional room addition. Sutton ADU Houston builds sunrooms that handle Houston’s climate properly, with insulated glass, engineered roof ties, and slab or pier foundations matched to your existing structure. A basic sunroom addition in Houston typically runs $45,000 to $90,000 depending on size, glazing type, and whether you need HVAC tied into the space.
Houston Climate Considerations
Houston’s heat, humidity, and hurricane-season winds demand more from a sunroom than a mild-climate build. We spec low-E insulated glass, reinforce roof-to-wall connections, and angle overhangs to cut direct summer sun while preserving winter light. These aren’t upgrades, they’re how a sunroom survives here.
Foundation and Permits
Sunrooms attached to your home in Houston typically require a permit, and the foundation method depends on your soil. We handle both. Your written estimate includes the permit work and the foundation plan, so you won’t discover a surprise line item halfway through.
Second Story Addition Contractor
A Second Story Addition Contractor in Bellaire builds upward instead of outward, adding a full or partial floor above your existing home. Houston homeowners choose second-story additions when lot size limits horizontal expansion but the family still needs more bedrooms, bathrooms, or a dedicated home office. Sutton ADU Houston has completed second-story additions throughout the Houston area, and we handle the structural engineering, foundation verification, stair placement, and roof integration as one coordinated build. A second-story addition in Houston typically runs $200,000 to $400,000 depending on square footage and whether the existing foundation requires reinforcement.
Structural Verification First
Before we quote a second-story addition, we verify what your existing slab or pier-and-beam foundation can carry. Houston’s expansive clay soil shifts with moisture, and some older foundations need selective reinforcement. We include that assessment in your written price, so there’s no surprise engineering bill after the quote.
Living Through the Build
A second-story addition is one of the more disruptive projects, because the roof comes off and the work happens above your head. We sequence the build to keep the lower level protected, and we communicate every phase before it starts. You’ll know who is on-site each day, and their name and photo arrive before they do.
Garage Addition Contractors
Garage Addition Contractors build attached or detached garage structures that can serve as vehicle storage, workshop space, or a future ADU conversion. Houston homeowners add garages when the existing carport isn’t cutting it, when they need secure storage for tools and equipment, or when they’re planning ahead for a future conversion. Sutton ADU Houston builds garages that are structurally ready for a future conversion to living space, with stem-wall foundations and electrical capacity sized accordingly. A garage addition in Houston typically runs $35,000 to $85,000 for a two-car attached or detached structure, before conversion finishes.
Built for Future Conversion
We pour stem-wall foundations and size the electrical panel for future living-space loads. That costs slightly more up front but saves you $15,000 to $25,000 if you later convert the garage to an ADU or rental unit. You won’t have to tear out drywall or upgrade service later.
Detached vs. Attached Tradeoffs
Detached garages offer better noise isolation and easier future ADU conversion, while attached garages are cheaper per square foot and keep you out of the rain. We walk through both options with you before the estimate, using your lot’s setbacks (the required gap between the structure and property line) to figure out what actually fits.
Bathroom Addition Contractor
A Bathroom Addition Contractor adds a full or half bath to a home that doesn’t have enough for its occupants. Houston homeowners add bathrooms most often for growing families, aging parents moving in, or a primary suite that needs its own bath instead of sharing a hall bath. Sutton ADU Houston handles the plumbing rough-in, waterproofing, ventilation, and finish work as one crew under one written price. A bathroom addition in Houston typically runs $25,000 to $65,000 depending on whether it’s a half bath or full bath, the distance from existing plumbing lines, and finish level.
Plumbing Distance Drives Cost
The biggest cost variable in any bathroom addition is how far the new drains need to run to tie into existing waste lines. A bathroom directly above or beside existing plumbing might come in near the bottom of that range. A bathroom on the opposite side of the house with a slab foundation runs higher. We show you the plumbing path before we quote.
Ventilation and Houston Humidity
Houston bathrooms fail early when the exhaust fan is undersized or vented into the attic instead of outside. We size and vent every bath fan to the exterior, and we use moisture-rated drywall and proper waterproofing at the shower and tub. Mold isn’t something you should have to think about in a brand-new bathroom.
Bedroom Addition Contractor
A Bedroom Addition Contractor builds additional sleeping rooms, either as a ground-floor extension or a bump-out on an existing wall. Houston homeowners add bedrooms when the household grows, when they need a true guest room, or when a home office needs to convert back to a bedroom. Sutton ADU Houston builds bedroom additions to code with proper egress windows, closet dimensions, and HVAC balancing. A bedroom addition in Houston typically runs $30,000 to $85,000 depending on size, whether it’s a bump-out or full extension, and whether it includes an attached bath.
Egress and Code Compliance
A legal bedroom in Houston requires an egress window large enough for a person to exit through in an emergency, along with minimum ceiling height and closet specifications. We handle all of that in the permit drawings. If you’re planning to list the home later, a permitted, code-compliant bedroom is the difference between a four-bedroom listing and a three-bedroom with a bonus room.
HVAC Balancing for Comfort
A room addition that’s under-served by the existing HVAC system will be hot in August and cold in January. We calculate the load for the new space and either extend existing ductwork or spec a ductless mini-split for the room. Your written estimate accounts for comfort, not just square footage.
Brands We Service
We work regularly with Dvele and Mighty Buildings prefab systems, which gives us a head start on any ADU project you’re considering from those manufacturers. Dvele units arrive with integrated smart-home systems and factory-sealed envelopes, and we handle the site prep, foundation, utility connections, and finish work in Houston’s permit environment. Mighty Buildings uses panelized construction that goes up faster than traditional framing, which suits Houston lots with tight access or HOA time restrictions.
We also have hands-on experience with Plant Prefab units for homeowners who want a plant-built panel system with architectural flexibility. Whether you have one of these brands already on order or you’re comparing them against a conventional stick build, we can help you understand what works for your lot and budget.
Signs You Need a Pro Right Now
- Your foundation shows new cracking or movement. Houston’s expansive clay soil expands and contracts with every dry spell and rainy season. If you see stair-step cracks in brick or widening gaps around windows, an addition built on an unstable foundation will fail early. We assess the foundation condition before any addition gets quoted.
- Your electrical panel is already maxed out. An addition that pulls more amps than your panel can supply will trip breakers constantly and can overheat wiring. If you’re already running extension cords or turning off one appliance to run another, the panel needs an upgrade as part of the addition scope.
- Water stains appear on ceilings or walls. Houston’s humidity and heavy rain expose roof and flashing issues quickly. Adding a second story or sunroom to a home with an active leak means building the problem into the new work. We fix the water entry first, then build.
- Your lot’s setbacks leave almost no room outward. Houston’s building code requires a gap between your structure and the property line, and that gap varies by neighborhood and zoning. If a ground-floor addition won’t fit within your setbacks, a second-story addition or detached ADU might be the only legal option. We figure this out during the site assessment.
- You’re sharing one bathroom with too many people. This isn’t a comfort issue, it’s a daily bottleneck that gets worse every year. A bathroom addition solves it permanently and returns value when you sell. We price the plumbing path honestly so you know what you’re committing to.
Our Process, Step by Step
- 1
Site assessment and lot review. We walk your property, check setbacks, foundation condition, plumbing and electrical access, and drainage. You get an honest read on what’s buildable before any money changes hands.
- 2
Written plan and price. We deliver a written scope of work and a fixed price. No vague allowances, no “to be determined” line items. The price you see is the price you pay unless you change the scope in writing.
- 3
Permits and engineering. We pull the Houston permits, handle the structural and civil engineering, and coordinate with any HOA review process. You don’t chase paperwork. We do.
- 4
Build with verified crew. Every Sutton technician who comes to your property is background-checked, identity-verified, uniformed, and photo-badged. You receive their name and photo before arrival, every time. No exceptions.
- 5
Final walkthrough and 365-Day Done Right Promise. We walk the finished work with you, verify everything against the written scope, and hand over your 365-Day Done Right Promise in writing. If anything isn’t right within a full year, we make it right.
How Much Does Home Addition Contractor Cost in Houston?
A home addition in Houston typically runs $165,000 to $340,000 for a full room addition or garage conversion, while smaller projects like a bathroom addition or sunroom run $25,000 to $90,000. Detached ADUs in the 600 to 900 square foot range generally run $180,000 to $320,000 before site work. Second-story additions sit at the upper end, typically $200,000 to $400,000, because they require structural verification and roof removal.
What affects the price: your foundation condition, the distance from existing plumbing and electrical, the finish level you choose, and whether Houston’s permit office requires additional engineering for your soil type or flood zone. The biggest way to avoid overpaying is to get a written scope with real line items instead of allowances. Allowances are where unexpected costs hide. Your free estimate from Sutton ADU Houston includes a written price broken down by line item, so you can compare against any other contractor’s quote honestly.
Our Service Area Near Houston
Sutton ADU Houston serves the entire Houston metro area including The Woodlands, Pearland, Humble, League City, Atascocita, Baytown, Mission Bend, La Porte, Rosenberg, Fresno, and Cinco Ranch. We also provide Home Addition Contractor in The Woodlands and Home Addition Contractor in Pearland service with the same Threshold Standard and written pricing. If you’re in a surrounding community and wondering whether we cover your street, call us. We’ll tell you honestly whether we can get a crew to your lot.
Serving Houston, TX - Our Local Coverage Area
We’re based in the Houston area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
Frequently Asked Questions About Home Addition Contractor in Houston
A home addition contractor handles the planning, permits, foundation work, framing, electrical, plumbing, HVAC, and finish work for adding livable square footage to your home. Sutton ADU Houston manages the entire project from site assessment through final walkthrough with one written scope and one fixed price. You deal with one point of contact from start to finish. Call (940) 242-3207 for a free estimate on your specific addition.
Most home additions in Houston take 3 to 7 months from permit approval to final walkthrough. A bathroom addition might take 6 to 10 weeks, a sunroom 8 to 12 weeks, and a second-story addition 5 to 7 months because of the structural work and roof sequencing. Houston’s permit office timing and weather both factor into the schedule. We’ll give you a written timeline with your estimate so you can plan around the build.
A home addition in Houston typically runs $165,000 to $340,000 for a full room addition or garage conversion, with smaller projects like bathrooms and sunrooms running $25,000 to $90,000. Detached ADUs generally run $180,000 to $320,000 before site work. Your exact price depends on square footage, foundation condition, plumbing distance, and finish level. A free estimate from Sutton ADU Houston gives you a written line-item price so you know exactly what you’re paying for.
Yes, we work with Dvele and Mighty Buildings prefab systems as well as Plant Prefab and other recognized ADU lines. We handle the Houston site prep, foundation, utility connections, and finish work for factory-built units. If you’re comparing a prefab ADU against a conventional build, we can help you understand the real cost difference on your lot. Call (940) 242-3207 and we’ll walk through your options honestly.
If a previous contractor left your addition with a structural issue, a leak, or a code violation, we can assess it and give you a written plan to correct it. We’re not a 24/7 emergency demolition crew, but we do answer calls at all hours, and we’ll get a verified technician to your property as quickly as our schedule allows. The 365-Day Done Right Promise means we stand behind the work we complete, so if something fails, we come back.
Every project comes with the 365-Day Done Right Promise in writing. If any element of the work isn’t right within one full calendar year from project completion, Sutton ADU Houston makes it right at no cost to you, including a free second visit. That covers defects in workmanship, not normal wear or homeowner modifications. The promise is stamped on your project documents, not just mentioned in a sales conversation.
Start by gathering any HOA documents or deed restrictions that might affect what you can build, then clear the area around the planned addition so we can assess the site properly. Think through how you’ll use the space and what finish level you actually want, because that drives the price more than anything else. We handle the permits, engineering, and construction planning after that. Miles Hartwell and the team at Sutton ADU Houston will walk you through every step before you commit to anything.
Schedule Your Home Addition Contractor Service in Houston Today
You don’t have to settle for a vague estimate and an unfamiliar crew. Call (940) 242-3207 and you’ll reach a live person who can answer your questions and schedule your free site assessment. Every project gets a written price before any work starts, every technician arrives with a name, a face, and a photo badge, and every build carries the 365-Day Done Right Promise. That’s how a home addition should work in Houston.
Written by Miles Hartwell, Owner at Sutton ADU Houston, serving Houston since 2006.
