An Austin-area patio should sit on a compacted base suited to your soil, slope away from the house, and have control joints plus an isolation joint at the foundation. Plan shade and lighter finishes for summer heat, and check HOA approval, city permits for covered structures and impervious cover limits before you design a large slab.
Last updated
Austin's long outdoor season makes a patio one of the most used spaces at many homes. Projects range from extending a small builder patio off the back door to a large slab for an outdoor kitchen, fire pit or shade structure. Whatever the size, a patio here has to deal with soil movement, strong sun and heavy bursts of rain.
Plan for heat and shade
- Orientation. A west-facing patio in an Austin summer gets intense afternoon sun. Plan shade from trees, a pergola or a roofed structure if you want to use it in July.
- Color and finish. Lighter colors and textured finishes stay cooler underfoot than dark, smooth ones.
- Future structures. Covered patios, pergolas and outdoor kitchens add weight and often need footings and a building permit. Tell the contractor about future plans before the pour.
Base work for Austin soils
On the blackland clays common east of I-35, a patio can rise and fall as the soil swells in wet months and shrinks in drought. Good practice includes removing soft or organic soil, compacting the subgrade, placing a compacted base, and reinforcing the slab so cracks stay tight. Disturbed soil near the house is often loose backfill from construction, which can settle under a new patio if it isn't compacted or replaced. In the Hill Country west of the fault, rock close to the surface can make digging slow and may affect cost, and uneven rock ledges should be leveled out with base material so the slab bears evenly.
Drainage first
A patio should slope slightly away from the house. Just as important is where the runoff goes next. Central Texas storms can drop a lot of rain quickly, and a new slab that sheds water toward the foundation or a neighbor's yard creates a new problem. On clay, water that soaks in next to the foundation can also affect how the house moves, so grade the edges to carry water away.
Joints at the house
Control joints divide the patio into roughly square panels so shrinkage cracks form along the joints. Where the patio meets the house, an isolation joint lets the slab and foundation move separately. Some contractors dowel a patio to the foundation and some deliberately don't; ask which approach they recommend for your soil and why.
Permits, HOAs and impervious cover
Whether a ground-level patio needs a permit depends on the city. Covered patios and roof structures generally do. Many Austin-area subdivisions have HOAs that require architectural approval before new concrete. Inside the City of Austin, zoning limits how much of a lot can be impervious cover, and patios count toward it. Lots over the Edwards Aquifer recharge or contributing zones in Travis, Williamson and Hays counties can also fall under TCEQ rules when impervious cover goes above certain levels. Check before you design a large slab.
Finish options
- Broom finish: simple, slip-resistant and economical.
- Exposed aggregate: textured, good traction, hides dirt.
- Stamped or colored: see stamped and decorative concrete.
- Light sandblast or salt finish: subtle texture that some homeowners like for pool areas.
Questions to ask
- What base and reinforcement will you use for my soil?
- Where will water go after it leaves the patio?
- How will you join the patio to the house?
- Does my city or HOA need to approve this, and who submits it?
Ready to plan it? Request a patio contractor and share a photo of the space.
See how it works
Frequently asked questions
Does a patio count toward impervious cover in Austin?
Yes. Patios, driveways and sidewalks count as impervious cover, and zoning in the City of Austin limits how much of a lot can be covered. Over the Edwards Aquifer, TCEQ rules can also apply above certain levels. Check your lot's limits before adding a large slab.
Do I need a permit for a concrete patio?
It depends on the city. A ground-level slab may not need a building permit in some places, while covered patios and roof structures generally do. HOAs often require approval either way. Check with your city and HOA.
How do I keep a patio from cracking on clay?
No slab is crack-proof, but good base preparation, reinforcement, closely spaced joints, careful curing and drainage that keeps water from soaking the soil next to the slab all reduce cracking and movement.
Sources and further reading
- American Concrete Institute (ACI)
- Portland Cement Association (PCA)
- Bureau of Economic Geology, UT Austin: Mount Bonnell and the Balcones Fault Zone
- City of Austin Transportation and Public Works: Right-of-Way Contractors
- City of Austin Development Services: Trees on Residential Property
- TCEQ: Edwards Aquifer rules for private residences
- City of Georgetown permits
- City of Leander: Driveway permit submittal packet
- City of Lakeway: Building applications and fees
- TxDOT Access Management Manual: Driveway permits
- Texas Department of Licensing and Regulation (TDLR)
- Texas811: Call before you dig