ADUs, garage apartments and guest houses in Houston
A second small home on your lot: for parents, grown kids, guests or rental income. We check your deed restrictions and flood zone first, then design, permit and build it.
Quick answer: In Houston, a garage converted into an apartment usually costs $60,000–$110,000, and a new detached guest house of 400–600 square feet runs about $140,000–$220,000. Houston allows a second dwelling of up to 1,500 square feet on most single-family lots, but your deed restrictions decide first: many subdivisions don’t allow one.
- Written, itemized priceScope, schedule and cost before you sign
- Permits in our nameDrawings, inspections and HOA approval handled
- Licensed trades, insuredTexas-licensed plumbing, electrical and HVAC
- 2-year written warrantyTransferable if you sell
What’s included
- Deed restriction, flood zone and easement check before design
- Floor plan, engineering and permit drawings
- Foundation, framing, roofing and exterior matched to your home
- Kitchen or kitchenette and full bathroom
- Plumbing, electrical and mini-split HVAC by licensed trades
- Separate meter and address when you want one
ADUs & guest houses projects we build
Garage apartments
A new two-story garage with living space above, or a second floor added over an existing detached garage. The classic Houston ADU.
Backyard cottages and guest houses
A detached one-story unit with its own entry, kitchen and bath, sized and placed to keep your yard usable.
Detached garage to ADU
The lowest-cost path when the slab and walls are sound: insulate, plumb, wire, condition and finish.
Detached garage to ADU: cost and detailsAttached in-law suites
A suite connected to the house with its own entry. Often the best choice for aging parents.
Attached in-law suites: cost and detailsCan you build one on your lot?
- Deed restrictions: Houston has no zoning, so recorded deed restrictions decide. Many master-planned communities prohibit a second dwelling no matter what the city allows.
- Size: the city allows a second unit of up to 1,500 square feet. Up to 1,000 square feet needs no extra parking space; larger needs one.
- Setbacks and fire separation: walls close to the property line need fire-rated construction under the residential code.
- Floodplain: in a mapped floodplain the new floor must sit at the required elevation, which can change the foundation design.
- Utilities: the route for sewer, water and power often costs more than the finishes. We plan it before you commit.
Planning to rent it out?
A long-term rental is the simplest use. If you plan short-term rentals, Houston now requires annual registration for short-term rental properties, and hotel occupancy tax applies. Check your deed restrictions too: many ban short-term rentals outright.
Design ideas for your ADU project
Design concepts showing the kind of work we build. Photos of finished Houston jobs are added as projects complete.
ADUs & guest houses cost in Houston
Typical ranges for full-service work in Greater Houston, reviewed every year.
| Project | What it usually includes | Typical Houston range |
|---|---|---|
| Detached garage to ADU | Insulation, kitchenette, bath, HVAC, finishes on an existing structure | $60,000–$110,000 |
| New guest house, 400–600 sq ft | Foundation, full build, kitchen, bath, utilities | $140,000–$220,000 |
| Larger ADU or garage apartment | Two-story garage apartment or 800+ sq ft cottage | $225–$325 per sq ft |
Ranges are for full-service work in Greater Houston, including design, permits, licensed trades and cleanup. They are based on 2025–2026 Houston data from Remodeling’s Cost vs Value report, Angi and Block Renovation, plus our own pricing. Your written estimate is itemized for your home.
Estimate your ADU project
Pick the closest match and set the size. Then get your exact number, free.
1 Which fits best?
Typical Houston range
$140k – $220k
ADUs & guest houses · New guest house, 400–600 sq ft. Based on 2025–2026 Houston data and our own pricing. Your home decides the real number.
Free visit · written, itemized price · no pressure
Permits
Inside the City of Houston, an ADU needs a building permit plus electrical, plumbing and mechanical permits, and the application includes a declaration that it doesn’t violate your deed restrictions. Floodplain lots get floodplain review, and a separate meter needs its own address. Outside the city, the county, your MUD and your HOA set the rules. We handle all of it.
Read our Houston permit guideHow your ADU project runs
- 1
Tell us
Call, WhatsApp or the form. We reply within one business day.
- 2
Visit and design
We measure, listen and sketch options in your home.
- 3
Written price
Scope, materials, schedule and cost in writing.
- 4
Permits
Plans to your city, plus HOA approval if needed.
- 5
Build and warranty
One project manager, photo updates, final walkthrough.
Questions about adus & guest houses
Can I build a guest house in my backyard in Houston?
Usually yes inside city limits, up to 1,500 square feet, if your deed restrictions allow a second dwelling. Read your recorded restrictions first; many subdivisions prohibit it.
How much does a garage apartment cost in Houston?
Converting an existing detached garage typically costs $60,000–$110,000. A new two-story garage with an apartment above usually runs $225–$325 per square foot of living space.
Does an ADU need its own parking space in Houston?
Not if it is 1,000 square feet or smaller. A unit of 1,001–1,500 square feet needs one additional parking space.
Can I rent out my ADU in Houston?
A long-term rental is generally allowed if your deed restrictions permit a second unit. Short-term rentals must be registered with the city each year and collect hotel occupancy tax, and many HOAs ban them.
How long does it take to build an ADU?
Plan 2–3 months for design, deed-restriction review and permits, then 4–6 months to build a detached unit. A garage conversion is usually 2–3 months of construction.
Will an ADU raise my property taxes?
Yes. The new living area is added to your appraised value. The homestead cap limits yearly increases on the existing home, but new construction is added at full value the first year.
Where we build ADU projects
Ready to talk about your ADU project?
Free in-home estimate with a written scope, price and schedule.
- Free in-home visit
- Written, itemized price
- 2-year written warranty
