An ADU builder in Houston is a licensed contractor who designs and constructs accessory dwelling units — detached backyard units, garage conversions, attached additions, and junior ADUs (JADUs). Because an ADU is a complete second dwelling, the builder coordinates foundation, framing, plumbing, electrical, and HVAC work and pulls it through Houston's permit process and utility connections. Not every general contractor has built one, so the right builder is one with ADU-specific experience in Texas.
What ADU Builders Cost in Houston [10][11][12]
Based on our Houston cost data, expect the following ranges from local ADU builders. Quotes for the same scope typically vary 20-40% between contractors, so getting at least three bids is the single best way to control cost.
| New Detached ADU (all-in) | $140,000-$260,000 |
| Cost per Sq Ft | $225-$350 |
| Garage Conversion | $60,000-$110,000 |
| Prefab / Modular ADU (installed) | $150,000-$300,000 |
| City Permit & Plan Review | Set by the City Fee Schedule (CPI increase of 1.391% on Jan 1, 2026): minimum building permit $91.06, minimum plumbing permit $97.56, administrative fee $33.56; the full residential fee formula was not readable this pass, so price your project with HPC's Fee Calculator. |
| Impact Fees | No general residential impact fee. Water and wastewater impact fees (Ch. 47 Arts. IX-X) are charged per service unit on 'new development' that adds capacity demand, at rates set in the City Fee Schedule (water-fee indexing resumed July 1, 2026, § 47-384); whether a second unit on the existing meter is assessed depends on the connection — ask HPC Impact Fee Administration. |
For a full line-item breakdown, see our Houston ADU cost guide. To confirm what you're allowed to build before you hire, review the Houston ADU rules (max detached size: 1,500 sq ft. § 42-1 defines single-family residential to include 'a detached second dwelling unit of not more than 1500 square feet'; the cap was increased by the Livable Places amendments (Ord. 2023-801, eff. Nov 27, 2023). The code does not say how the area is measured; deed restrictions may set a lower cap or bar a second unit entirely.; owner-occupancy: Not required. Chapter 42 contains no owner-occupancy, rental or deed-covenant condition for a second dwelling unit; either unit may be rented long-term. Recorded deed restrictions may impose their own limits.).
Get Free ADU Quotes in Houston
Tell us about your project and we'll pass it to ADU builders serving Houston. Free, no obligation — you choose who to work with. We don't have builders in every area yet; if nobody covers yours, we'll email you to say so.
Takes about a minute.
Up to 5 independent local ADU builders — never more, and we tell them nothing you don't submit here.
Compare quotes, verify license & insurance, hire (or don't). No spam either way.
🔒 Your info is secure. We share it only with contractors quoting your project. No spam, no obligation.
Just browsing? Search ADU builders near you by ZIP code.
How to Vet an ADU Builder in Houston
- License: Confirm a current contractor's license in Texas and that it's in good standing. Ask for the license number and verify it with the state board.
- ADU-specific experience: Ask how many ADUs they've completed in or near Houston and request addresses or photos. ADU permitting and setbacks differ from a kitchen remodel.
- Portfolio & references: Get references from recent ADU clients and, if possible, visit a finished unit.
- Insurance: Verify general liability and workers' compensation coverage. Ask for a certificate of insurance.
- Written, detailed bid: Insist on an itemized, fixed-price or clearly-scoped bid — not a verbal estimate. It should state whether permits (Set by the City Fee Schedule (CPI increase of 1.391% on Jan 1, 2026): minimum building permit $91.06, minimum plumbing permit $97.56, administrative fee $33.56; the full residential fee formula was not readable this pass, so price your project with HPC's Fee Calculator.), plan check (Not published; Houston Public Works reviews residential plans through ProjectDox and ILMS, with resubmittal cycles as needed.), and impact fees (No general residential impact fee. Water and wastewater impact fees (Ch. 47 Arts. IX-X) are charged per service unit on 'new development' that adds capacity demand, at rates set in the City Fee Schedule (water-fee indexing resumed July 1, 2026, § 47-384); whether a second unit on the existing meter is assessed depends on the connection — ask HPC Impact Fee Administration.) are included.
- Permit handling: Confirm they manage Houston's permit process ("Building permit through the Houston Permitting Center (Houston Public Works, 1002 Washington Ave): plans go in through iPermits/ProjectDox, the Planning Department's site-plan review checks building lines, lot size and parking, then electrical, plumbing and mechanical permits and inspections follow. No hearing or discretionary approval; a replat is needed only if the lot is being split.", typically Not published. The city posts no residential plan-review target; ask the Houston Permitting Center (832-394-9000) for current cycle times.) and who is responsible if revisions are required.
- Payment schedule: Avoid large upfront payments. A reasonable schedule ties payments to completed milestones.
Questions to Ask Before You Hire
- How many ADUs have you built in Houston in the last two years?
- Is your bid fixed-price, and what would trigger a change order?
- Are permits, plan check, and utility connection fees included?
- What's a realistic timeline, including permit review (Not published. The city posts no residential plan-review target; ask the Houston Permitting Center (832-394-9000) for current cycle times.) and construction?
- Who is my point of contact and how are delays communicated?
- What warranty do you provide on workmanship?
- Can you share three recent Texas ADU client references?
Finance Your ADU Project
Most ADU projects are funded through HELOCs, construction loans, or cash-out refinancing. Compare rates from top lenders.
Some links on this page are affiliate links. We may earn a commission at no extra cost to you. Learn more
Are you an ADU builder? Get Houston leads
Homeowners on this page submit real ADU project requests in Houston. Each one goes to up to five local builders — that is what the homeowner agrees to — so claiming never takes it from anyone and there is no bidding. In practice far fewer ever make contact, which is why the number is five rather than three. A flat $50 only on the leads you accept: no subscription, no contract, and you deal with the homeowner directly.
Get Houston ADU Leads →Frequently Asked Questions
How much do ADU builders charge in Houston?
How do I find a good ADU builder in Houston?
Do ADU builders in Houston handle permits?
How long does it take to build an ADU in Houston?
Get Free ADU Builder Quotes in Houston
Compare bids from experienced local Houston ADU builders. Free, no obligation.
Get Free Quotes →