Need more space without moving? An accessory dwelling unit might be the answer. ADUs — also called guest houses, in-law suites, casitas, or backyard cottages — are secondary living spaces built on your existing property. They come with their own entrance, kitchen, bathroom, and sleeping area.
Houston homeowners are building ADUs for all kinds of reasons. Rental income. Space for aging parents. A private home office. A place for adult children to land. Whatever your reason, EZ Home Remodel has the experience to make it happen.
We’ve spent over 10 years building ADUs across the Houston metro area. Garage conversions. Detached backyard units. Above-garage apartments. We handle design, permits, construction, and inspections — everything from the first conversation to handing you the keys.
No subcontractors. No finger-pointing. Just one team that builds it right and stands behind the work.
What Is an ADU?
ADU stands for Accessory Dwelling Unit. It’s a self-contained living space located on the same property as a primary residence. Unlike a spare bedroom or basement apartment, an ADU is a complete home with its own:
- Private entrance
- Full kitchen with appliances
- Bathroom
- Sleeping area
- Heating and cooling system
- Electrical panel
- Water and sewer connections
ADUs go by many names depending on the region and configuration — granny flat, mother-in-law suite, backyard cottage, guest house, carriage house, or casita. Regardless of what you call it, the function is the same: an independent living space on your property.
Types of ADUs
| ADU Type | Description | Best For |
|---|---|---|
| Garage Conversion | Transform the existing garage into a living space | Budget-conscious projects, faster timeline |
| Detached ADU | New standalone structure in the backyard | Maximum privacy, custom design flexibility |
| Above-Garage ADU | Living space built on top of an existing or new garage | Preserving parking, maximizing lot space |
| Attached ADU | An addition connected to the main house with a separate entrance | Easy access to the main home, shared utilities |
| Basement Conversion | Convert the existing basement to a living space | Homes with existing basements (rare in Houston) |
Our ADU Construction Services
We build every type of ADU that works for Houston properties. Here’s what we offer:
Garage Conversions
Converting your existing garage into a living space is the fastest and most affordable way to add an ADU. The structure already exists — we transform it into a comfortable, code-compliant home.
What’s Involved in a Garage Conversion
- Insulating walls, ceiling, and garage door opening
- Installing drywall and interior finishes
- Adding windows for natural light and ventilation
- Pouring new flooring or leveling an existing slab
- Running electrical circuits and adding a subpanel
- Installing plumbing for the kitchen and bathroom
- Adding HVAC system (mini-split or ducted)
- Building out the kitchen with cabinets and appliances
- Constructing a full bathroom
- Creating a separate entrance
Garage Conversion Benefits
- Lower cost than new construction
- Faster timeline — typically 2-4 months
- Existing foundation and structure
- No loss of yard space
- Easier permitting process
Considerations
- You’ll lose covered parking
- May need to add windows for egress requirements
- The garage slab may need modification for plumbing
- HOA restrictions may apply in some neighborhoods
Detached Backyard ADUs
A detached ADU is a brand-new structure built in your backyard. This option offers the most significant design flexibility and the highest level of privacy for both the main house and the ADU occupants.
Detached ADU Features
- Custom floor plans from 400-1,200 square feet
- Studio, one-bedroom, or two-bedroom configurations
- Full kitchen with standard or compact appliances
- Complete bathroom — shower or tub/shower combo
- Independent HVAC system
- Separate electrical meter (optional)
- Private outdoor space or patio
- Covered parking or carport (optional)
Foundation Options
| Foundation Type | Description | Best For |
|---|---|---|
| Slab-on-Grade | Concrete poured directly on the ground | Most Houston ADUs, flat lots |
| Pier and Beam | Raised structure on concrete piers | Flood-prone areas, sloped lots |
| Crawl Space | Raised foundation with access below | Easy utility access, drainage concerns |
“A detached ADU is basically building a small house from scratch. You need someone who understands foundations, framing, roofing, plumbing, electrical, HVAC — the whole picture. That’s why we keep everything in-house. One team, one responsibility, one warranty.”
— Mike E., Owner of EZ Home Remodel
Above-Garage ADUs
An above-garage ADU — sometimes called a carriage house — puts living space on top of your garage. This design preserves your parking while maximizing the use of your lot.
Above-Garage ADU Options
- Build above the existing garage (if structurally sound)
- Construct a new garage with an ADU above
- Replace the old garage with a new two-story structure
Design Considerations
- Exterior staircase or interior access from garage
- Sound insulation between the garage and the living space
- Structural reinforcement for existing garages
- Height restrictions based on Houston zoning
- Setback requirements from property lines
Benefits
- Keeps parking covered and secure
- Minimal footprint on yard space
- Clear separation from the main house
- Good rental appeal
Attached ADUs
An attached ADU connects directly to your main house but has its own private entrance. This configuration works well for families who want proximity — like housing for aging parents, while maintaining separate living spaces.
Attached ADU Features
- Direct connection to the main home (optional internal door)
- Separate exterior entrance for privacy
- Shared or separate utilities
- Can be a single-story or two-story addition
Common Configurations
- Side addition with a separate entrance
- Rear addition extending into the backyard
- Second-story addition above garage or existing space
- Converted portion of existing home with new entrance
ADU Floor Plans and Sizes
ADUs range from compact studios to spacious two-bedroom units. The right size depends on your lot, budget, and intended use.
Common ADU Sizes
| Size | Square Footage | Typical Layout | Best For |
|---|---|---|---|
| Compact Studio | 300–450 sq ft | Open living/sleeping, kitchenette, bath | Single occupant, home office, short-term rental |
| Standard Studio | 450–600 sq ft | Open plan with defined areas, full kitchen, bath | Single occupant or couple, rental unit |
| One-Bedroom | 600–800 sq ft | Separate bedroom, living area, kitchen, bath | Long-term rental, aging parent, adult child |
| Large One-Bedroom | 800–1,000 sq ft | Spacious bedroom, open living, full kitchen, bath | Comfortable independent living |
| Two-Bedroom | 1,000–1,200 sq ft | Two bedrooms, living room, kitchen, 1-2 baths | Small family, roommates, premium rental |
Space Planning Tips
- Open floor plans make small spaces feel larger
- Murphy beds and convertible furniture maximize flexibility
- Compact appliances save kitchen space without sacrificing function
- Built-in storage reduces clutter
- High ceilings and large windows add volume and light
- The outdoor living space extends the usable area
Why Houston Homeowners Build ADUs
ADUs serve many purposes. Here’s why our clients build them:
Rental Income
Houston’s rental market is strong. A well-built ADU can generate $1,000-$2,500 or more per month, depending on size, location, and finishes. Many homeowners use rental income to offset their mortgage or fund retirement.
Rental Potential by ADU Type
| ADU Type | Typical Monthly Rent (Houston) |
|---|---|
| Studio (400-500 sq ft) | $1,000 – $1,400 |
| One-Bedroom (600-800 sq ft) | $1,300 – $1,800 |
| Two-Bedroom (1,000+ sq ft) | $1,800 – $2,500+ |
Note: Rental rates vary significantly by neighborhood, finishes, and amenities. Inner-loop Houston locations typically command higher rents than suburban areas.
Multigenerational Living
More families are choosing to live together across generations. An ADU provides independent living space for aging parents or adult children while keepingthe family close. Everyone maintains privacy while staying connected.
Benefits for Multigenerational Families
- Aging parents live independently but nearby
- Adult children can save money while establishing careers
- Grandparents can help with childcare
- Family members can assist with elder care
- Shared expenses reduce financial burden
- Private space prevents household friction
Home Office or Studio
Remote work is here to stay. An ADU provides a dedicated workspace completely separate from your main home — no distractions, no interruptions, and a real commute (even if it’s just across the backyard) that creates work-life boundaries.
ADU Workspace Uses
- Home office for remote workers
- Art or photography studio
- Music practice and recording space
- Therapy or consulting office
- Workshop or maker space
- Yoga or fitness studio
Guest Accommodations
A dedicated guest house means visitors have their own space — and so do you. No more giving up bedrooms or sharing bathrooms. Guests get privacy and comfort. You maintain your routine.
Property Value
ADUs add usable square footage and income potential to your property. While exact value increases depend on many factors, well-built ADUs typically add significant value at resale — especially in desirable Houston neighborhoods.
“I tell clients to think about ADUs in three ways: what it does for you now, what it could do for you later, and what it does for your property value. Most ADUs we build serve one purpose today and a different purpose five years from now. That flexibility is the real value.”
— Mike E., Owner of EZ Home Remodel
ADU Construction Cost in Houston
ADU costs vary significantly based on type, size, finishes, and site conditions. Here’s what Houston homeowners typically invest:
| ADU Type | Typical Cost Range | Timeline |
|---|---|---|
| Garage Conversion | $50,000 – $100,000 | 2–4 months |
| Detached ADU (400-600 sq ft) | $100,000 – $175,000 | 4–6 months |
| Detached ADU (600-1,000 sq ft) | $150,000 – $250,000 | 5–7 months |
| Above-Garage ADU | $120,000 – $250,000 | 4–6 months |
| Attached ADU Addition | $80,000 – $180,000 | 3–5 months |
| Finish Level | Cost Per Square Foot | What’s Included |
|---|---|---|
| Budget | $175 – $225 | Basic finishes, standard appliances, builder-grade fixtures |
| Mid-Range | $225 – $300 | Quality finishes, upgraded appliances, better fixtures |
| High-End | $300 – $400+ | Premium materials, custom features, luxury finishes |
What Affects the Price?
ADU Type
Garage conversions cost less because the structure exists. Detached ADUs require a new foundation, framing, roofing, and all utilities from scratch. Above-garage units may require structural reinforcement.
Size and Layout
The cost per square foot typically ranges from $200 to $350, depending on finishes. A 500-square-foot ADU costs less than a 1,000-square-foot unit, but larger ADUs often have lower per-square-foot costs due to economies of scale.
Site Conditions
Flat, accessible lots cost less to build on. Sloped sites, poor soil conditions, limited access, or the need to relocate utilities all add cost. Trees that need removal, existing structures that require demolition, and drainage issues also factor in.
Utility Connections
Distance from main utility connections affects cost. Running water, sewer, and electrical lines across a large backyard cost more than connecting to utilities near the main house.
Finishes and Features
Standard finishes keep costs down. Premium countertops, custom cabinets, high-end appliances, and luxury fixtures increase the budget. The same applies to flooring, lighting, and bathroom finishes.
Permits and Fees
Permit impact and utility connection fees vary by location. Budget $3,000-$10,000 or more for permitting and related costs in the Houston area.
Cost Per Square Foot Breakdown
| Location | Typical Setback |
|---|---|
| Rear property line | 3–5 feet minimum |
| Side property line | 3–5 feet minimum |
| Front property line | 25 feet minimum (ADUs typically in rear) |
| Distance from the main house | Varies — fire separation requirements apply |
Houston ADU Regulations and Permits
Houston is one of the more ADU-friendly cities in Texas, but there are still rules to follow. Understanding local regulations is critical before starting your project.
Houston ADU Zoning Basics
Houston doesn’t have traditional zoning like most cities, but deed restrictions and municipal codes still apply. Here’s what you need to know:
General Requirements
- ADUs are generally allowed on residential lots in Houston
- Property must have an existing primary residence
- ADU must be smaller than the primary residence
- Setback requirements apply (distance from property lines)
- Height restrictions vary by location
- Parking requirements may apply
- Deed restrictions may prohibit or limit ADUs in some subdivisions
Setback Requirements
Note: Setback requirements vary based on lot size, location, and specific municipal codes. We verify requirements for your property during the feasibility assessment.
Permits Required for ADU Construction
Building an ADU in Houston requires multiple permits. We handle the entire process:
- Building PermitRequired for all new construction and major renovations. Includes plan review and multiple inspections throughout construction.
- Electrical PermitRequired for all electrical work. Our licensed electricians pull permits and schedule inspections.
- Plumbing PermitRequired for all plumbing installations. Our licensed plumbers handle permits and inspections.
- Mechanical PermitRequired for HVAC installation. Covers heating, cooling, and ventilation systems.
- Foundation PermitRequired for new foundations. Includes soil testing and foundation inspections.
- Utility Connection PermitsRequired to connect water, sewer, and electrical service. May involve city utility departments and fees.
Inspection Process
ADU construction involves multiple inspections at key stages:
- Foundation inspection (before pouring concrete)
- Framing inspection (before closing walls)
- Rough electrical inspection
- Rough plumbing inspection
- Rough mechanical inspection
- Insulation inspection
- Final electrical inspection
- Final plumbing inspection
- Final mechanical inspection
- Final building inspection
- Certificate of Occupancy
We schedule all inspections and address any issues that arise. You receive a Certificate of Occupancy when everything passes, confirming that your ADU is safe, legal, and ready to occupy.
Deed Restrictions
Many Houston subdivisions have deed restrictions that may affect ADU construction. Before starting any project, we help you:
- Locate and review your deed restrictions
- Identify any language prohibiting secondary structures
- Understand size and placement limitations
- Determine approval processes (if HOA exists)
Some older Houston neighborhoods have minimal restrictions. Newer subdivisions often have strict HOA rules. We’ll help you understand what’s possible on your property.
“Permits protect you. A properly permitted ADU can be legally rented, adds to your home’s assessed value, and won’t cause problems when you sell. Unpermitted construction creates liability and headaches down the road. We do things the right way.”
— Mike E., Owner of EZ Home Remodel
Ready to Build Your ADU?
Stop thinking about it and start building. EZ Home Remodel has helped Houston homeowners add ADUs for over 10 years—from garage conversions and backyard guest houses to above-garage apartments and everything in between. We handle permits, construction, and inspections so you don’t have to.
Whether you want rental income, space for family, or a private home office, we’ll help you build an ADU that adds real value to your property and your life.
Fill out the form below or give us a call. Free consultations. Honest assessments. No pressure — just a straightforward conversation about what’s possible on your property.