Building Code Quick Reference
Bexar County · San Antonio Unified Development Code (UDC)
Everything you need to know about building in San Antonio, California — setback distances, height limits, lot coverage, FAR, parking requirements, and the issues that San Antonio plan checkers flag most often. Use this as a quick reference before designing or submitting plans.
Values shown for the most common residential zone. See full zone table below for all zones.
Each zone in San Antonio has different development standards. The table below shows setbacks (the minimum distance your building must be from each property line), maximum height, number of stories, lot coverage percentage, and Floor Area Ratio (FAR) for each residential zone.
| Zone | Front | Side | Rear | Height | Stories | Coverage | FAR |
|---|---|---|---|---|---|---|---|
| R-20 — Residential Estate | 30' | 10' | 25' | 35' | 2 | 35% | — |
| Large-lot estate residential. | |||||||
| R-4 — Residential Single-Family | 20' | 5' | 5' | 35' | 2 | 45% | — |
| Smallest SF lot zone. Common in older urban neighborhoods. | |||||||
| R-6 — Residential Single-Family | 25' | 5' | 20' | 35' | 2 | 45% | — |
| Most common SF zone in San Antonio. | |||||||
Parking is one of the most common plan check flags. San Antonio requires the following parking ratios for residential projects — make sure your site plan accounts for these before submitting.
Covered/enclosed required
Waived near transit
Standard residential
IBC/IRC as locally adopted. ADU rules set at city level.
→ Use our Parking Calculator to calculate your exact requirement.
Beyond zoning, San Antonio has general building requirements that apply to all residential construction. These are commonly referenced during plan check.
These are the issues that San Antonio plan reviewers flag most frequently on residential submissions. Addressing these before you submit can save one or more correction cycles (each adding 2–4 weeks to your timeline).
Check San Antonio's planning department website for their zoning map, or search your address on our parcel search tool. Your zone code (R1, R2, etc.) determines which row in the table above applies to your property. You can also call San Antonio's planning counter for a quick zoning verification.
Initial plan review in San Antonio typically takes 4–8 weeks. If corrections are required (which is common), each resubmission adds another 2–4 weeks. Running a pre-submission plan check can eliminate the most common correction items and save one or more review cycles.
Yes. Under California state law, San Antonio must approve ADUs that meet state standards — no discretionary review required. Detached ADUs can be up to 1,200 sqft with only 4' rear and side setbacks. Use our San Antonio ADU Eligibility Checker to see what you can build on your lot.
The top reasons are setback violations (measuring from the wrong reference point), height calculation errors (using the wrong grade measurement method), lot coverage exceeding the zone limit, insufficient parking, and missing energy code (Title 24) compliance. See the "Common Plan Check Flags" section above for San Antonio-specific issues.
The zoning standards above apply to standard residential projects. Specific overlays (historic districts, hillside areas, coastal zones) may have additional restrictions. Commercial and mixed-use zones have different standards. Always verify your specific zone and any applicable overlays with San Antonio's planning department.
Enter your project dimensions and we'll compare them against San Antonio's building codes. Catch setback violations, height issues, and parking shortfalls before they become correction letters.
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