Houston ADU permit requirements
Last reviewed: June 22, 2026
Quick answer
Permitting an accessory dwelling unit (ADU) in Houston, Texas means pulling a building permit from the local authority that issues it. ArchPermit tracks 16 source-cited requirements (11 required, the rest conditional) for this jurisdiction. Submittals go through iPermits + ProjectDox online portal. These requirements were last reviewed June 22, 2026; confirm the exact forms and fees with the local permitting authority.
A source-cited checklist of what an ADU (accessory dwelling unit) permit package needs in City of Houston. Every item links to its authoritative source; items that vary are flagged to confirm locally.
Houston has no zoning, so an ADU (the City's term is 'auxiliary unit (ADU)'; commonly 'garage apartment' or 'quarters') is broadly allowed and governed by Code of Ordinances Chapter 42 (development/platting, covering property use and setbacks) plus private recorded deed restrictions, rather than by a zoning district. Planning reviews the site plan for Chapter 42 (use, setbacks), Chapter 26 (parking), and Chapter 33 (trees). Platting/replat may be triggered by a change in use. ADU carve-outs: no landscaping requirement, and parking is scaled to ADU size (≤1,000 sf living = no added space). The exact ADU setback and size cap live in Chapter 42; confirm there.
- Building Permit Applicationrequired
Completed online via the iPermits portal.
source · reviewed 2026-06-22 - Calculation of Impervious Percentage (CE-1207)required
Impervious-cover calculation; also drives whether a Storm review is triggered (>65% impervious cover, or lot >15,000 sf).
source · reviewed 2026-06-22 - Complete Plan Setrequired
Construction-ready plans uploaded to ProjectDox; sheets may not be marked 'Preliminary' / 'Not for Construction.'
source · reviewed 2026-06-22 - Deed Restrictions Declarationrequired
Signed by the property owner and validated against HCAD; if ownership doesn't match HCAD, also upload proof of ownership.
source · reviewed 2026-06-22 - Door & Window Schedule + Wall Schedulerequired
List door/window sizes; key the wall schedule to the floor plan for all wall types; include energy-code details.
source · reviewed 2026-06-22 - Energy Code Documentsrequired
IC3, REScheck, or REM/Rate output matching the plans, or prescriptive energy requirements shown on the plans.
source · reviewed 2026-06-22 - Floor Plans (rooms labeled by use)required
Each room labeled by use, with partitions, windows, doors, and scope-of-work details.
source · reviewed 2026-06-22 - Grading Permits Worksheet (CE-1094)required
Grading/fill worksheet for the project.
source · reviewed 2026-06-22 - Site Planrequired
Always required: all buildings, off-street parking, and impervious areas, with dimensions matching the plat and survey.
source · reviewed 2026-06-22 - Stormwater Information Formrequired
Required for construction, additions, and sitework; completed/signed by the owner.
source · reviewed 2026-06-22 - Wastewater Capacity Reservation (WCR) Letterrequired
Water/sewer letter required for all new single-family residential construction; obtained separately via iPermits before plan approval.
source · reviewed 2026-06-22 - Access Agreement for Construction and Maintenanceconditionalverify locally
Required if proposed construction is less than three feet from an adjacent single-family residence's property line (the governing setback figure lives in Chapter 42; confirm).
source · reviewed 2026-06-22 - Elevation Certificate (floodplain)conditional
Required if the lot is in the 100-yr or 500-yr floodplain; sealed by a Texas surveyor or PE (a Mitigation Plan is also required).
source · reviewed 2026-06-22 - Sealed Structural / Architectural Sheetsconditional
Structural/architectural sheets sealed, signed, and dated by a Texas-licensed architect or engineer when required (foundation, framing, wall-section, windstrapping details).
source · reviewed 2026-06-22 - Subdivision Plat / Replat Referenceconditional
Required if the property is platted. Check building lines, easements, lot size, density. Platting may be required on a change in use.
source · reviewed 2026-06-22 - Survey (Texas Registered)conditional
Required for residential additions / garage conversions: property lines, easements, setback lines, and existing structures (a survey showing a small addition may serve as the site plan).
source · reviewed 2026-06-22
Houston ADU permit questions
- Do I need a permit to build an ADU in Houston?
- Yes. An accessory dwelling unit (ADU) in Houston requires a building permit. ArchPermit tracks 16 cited requirements for this jurisdiction (11 required, the rest conditional). Always confirm the exact forms, fees, and code edition with the local permitting authority that issues the permit.
- What does an ADU permit package require in Houston?
- Core required items include: Building Permit Application; Calculation of Impervious Percentage (CE-1207); Complete Plan Set; Deed Restrictions Declaration; Door & Window Schedule + Wall Schedule; Energy Code Documents, plus 5 more. Each requirement links to its authoritative source, and nothing is permit-ready until an independent licensed professional reviews and seals it.
- How are ADU permits submitted in Houston?
- Houston accepts permit submittals via iPermits + ProjectDox online portal. ArchPermit prepares a draft package you can submit there after a licensed architect reviews and seals it.