ADU builder in San Antonio, TX

Room for family or a tenant, right in your backyard.

Backyard cottages, garage conversions, attached units and garage apartments for San Antonio homeowners. Licensed and insured, with permitting handled for you.

Why owners here build

A place for aging parents · Long-term rental income · A grown kid's first place · A home office away from the house

Start my lot check
Small backyard home (ADU)

How much does an ADU cost in San Antonio?

As of October 2026, one published San Antonio guide estimates about $95,000 to $170,000 all-in for a detached ADU, counting design, permits and utilities, and about $40,000 to $80,000 to build a garage conversion or attached unit. Lot conditions, size and finish level move the final figure.

We price each project with a written, itemized quote after visiting the site. Read the San Antonio cost guide.

Build types

01Backyard cottageA detached unit of one or two stories, set apart from the house. 02Garage conversionThe garage you have, rebuilt inside to dwelling standards. 03Attached ADUAn addition with its own door, kitchen and bath. 04Garage apartmentA second-floor unit over parking or a workshop.

All four include design and permitting. San Antonio allows one ADU per eligible lot; see the size rules.

How it works

  1. 01Lot checkZoning, owner-occupancy, setbacks and deed restrictions.
  2. 02PlansSite plan, foundation, energy report and HVAC sizing.
  3. 03PermitFiled through BuildSA, with the recorded affidavit.
  4. 04BuildConstruction, inspections and a certificate of occupancy.

The full process, stage by stage.

Areas

San Antonio and four nearby cities. Without a statewide ADU law in Texas, every one of them writes its own rules, and Alamo Heights in particular differs sharply from San Antonio.

New BraunfelsOne accessory dwelling per lot in several districts.ADUs in New Braunfels SchertzA defined ADU use in the city's development code.ADUs in Schertz BoerneHill Country lots, rock and slope.ADUs in Boerne Alamo HeightsIts own city code, with tight limits on separate quarters.ADUs in Alamo Heights

San Antonio and every area we cover.

Find out what your lot allows

Give us an address and we will report back on what can be built there, at no cost. We cover San Antonio, New Braunfels, Schertz, Boerne and Alamo Heights.

No charge and no commitment. Your details are used only to answer your request.

San Antonio ADU guides

How much does an ADU cost in San Antonio? How big can an ADU be in San Antonio? Do I have to live on the property to build an ADU in San Antonio? Can San Antonio waive ADU permit and impact fees? How much rent can an ADU make in San Antonio? Can deed restrictions or an HOA block an ADU in San Antonio?