This is part of our Garage ADU series for San Antonio homeowners. Also in this series: cost · rules & permits · rental income · financing · timeline · FAQs.
Is a garage conversion the cheapest way to build an ADU?
Yes. Because the structure already exists, garage conversions are consistently the most affordable ADU type — often half the cost of a detached new build.
Do I need a permit to convert my garage?
Yes. Electrical, plumbing, and structural work all require permits and inspections. Unpermitted work can hurt resale value and complicate refinancing or sale.
Can I rent out my converted garage on Airbnb?
It depends on local short-term rental ordinances. Many cities allow long-term leases freely but restrict short-term stays. Check San Antonio’s STR rules before counting on Airbnb income.
Will I lose my parking?
The enclosed parking goes with the conversion. Many homeowners add driveway parking or a carport to compensate — and some jurisdictions require a replacement plan as part of approval.
Can my HOA stop me?
Possibly. Some San Antonio-area HOAs restrict or prohibit ADUs. Review your CC&Rs early — before spending money on design.
Will a garage conversion hurt my home’s resale value?
A permitted, well-built ADU typically adds value — appraisers count legal living square footage. An unpermitted conversion can do the opposite.
How much does it cost?
See our full breakdown: Garage Conversion ADU Cost in San Antonio. Short version: $15,000–$30,000 for basic living space, $35,000–$60,000+ for a full ADU with kitchen and bath.
How long does it take?
Plan 4–6 months from first conversation to move-in. Full detail: Garage Conversion ADU Timeline.
Is Your Garage a Candidate?
If your garage is structurally sound, your lot meets setback requirements, and your HOA allows it, you’re likely a strong candidate. The fastest way to find out is a free feasibility review — we’ll tell you straight whether the numbers and the rules work for your property.
Book a free estimate or start with our Casita / ADU Cost Guide for San Antonio & the Hill Country.