ADUs are allowed in AltonTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Alton, TX
Is your property eligible for an ADU?
# of Properties
1,871
Owner-occupied
8%
Zoning districts
16
Avg Home Value
$175,006
Median Lot Size
0.17 acres
Avg Income
$102,739
Residential Types:
1,871 housing units
Other
100%
Zoning Districts:
2,475 parcels · 16 districts
R-2
47%(1,165)
R-3
17%(417)
R-1
16%(387)
C-2
9%(233)
Other
11%(273)
ADU Rules
What can you build in Alton, TX?
Alton, TX follows state and local rules for Accessory Dwelling Units. Here is a concise overview of the local rules.
Eligibility
- –Internal / Attached ADU: By Right
- –Detached ADU: By Right
Interior / Attached ADU Size Limits
- –Maximum size of 50% of the primary building’s floor area
Detached ADU Size Limits
- –Maximum size of 50% of the primary structure’s square footage
Max Units
- –Accessory dwelling no larger than 50% of the square footage of the primary structure.
Owner Occupancy
- –No owner-occupancy requirement for ADUs.
Parking
- –0 spaces per ADU; no additional parking required; general off-street rules apply (reductions moot)
ADU State Law
What can you build in Texas?
- –Texas does not have a statewide ADU law. ADUs are regulated entirely at the local level.
- –ADU rules vary significantly by city, and many jurisdictions prohibit ADUs outright.
- –Counties generally lack zoning authority, but other restrictions may still apply outside city limits.
- –Outside city limits, ADU feasibility often depends on subdivision rules, deed restrictions, and septic or fire requirements.
- –Building/fire codes are set statewide, but whether an ADU is allowed is local zoning.
What's allowed on your lot?
These are the municipality-wide rules. What's allowed on a specific property also depends on state laws, setbacks, floor area ratio, lot coverage, environmental constraints, topography, and other property-specific factors. Search your address on FutureLot to see what's allowed on your property.
Check my propertyHow can we help you?
Get matched with trusted local builders
Understand what's allowed on your property
Learn the key rules and size limits for ADUs
Is your property eligible for an ADU?
ADU rules in other Texas municipalities
Rules change at the town line. Check the municipality your property is actually in.
Hidalgo County