Patio Calculator
Slab Results
| Application | Min Thickness | Recommended | PSI |
|---|---|---|---|
| Sidewalk / Walkway | 3" | 4" | 3000 |
| Backyard Patio | 3.5" | 4" | 3000-4000 |
| Residential Driveway | 4" | 5" | 4000 |
| Garage Floor | 4" | 5-6" | 4000 |
| Heavy Equipment Pad | 6" | 8" | 5000 |
Patio Thickness by Use Case
| Application | Min Thickness | Recommended | Reinforcement |
|---|---|---|---|
| Sidewalk / Walkway | 3.5" | 4" | Optional fiber |
| Patio | 4" | 4" | Mesh recommended |
| Residential Driveway | 4" | 5" | Mesh or rebar grid |
| Garage Floor | 4" | 5-6" | Rebar grid required |
| RV/Truck Pad | 6" | 6-8" | Heavy rebar grid |
| Shed Foundation (small) | 4" | 4" | Mesh |
| Pool Deck | 4" | 4-5" | Mesh + control joints |
| Hot Tub Pad | 4" | 6" | Rebar grid |
For freeze-thaw climates (Northeast, Midwest, Mountain West), add 1 inch to the recommended thickness. Always check your local building code -- some jurisdictions require 6" minimum for driveways regardless of use.
Patio Pour Checklist
- Excavate to depth. Slab thickness + base depth + 2" for forms = total dig depth. For a 4" slab on 4" base, dig 10" below final grade.
- Compact subgrade. Native soil should be compacted to 95% before adding base. Don't skip this on clay or recently disturbed soil.
- Lay 4" of crushed stone or roadbase. Compact in 2" lifts. 95% compaction is the target.
- Set forms. 2x4 lumber for 3.5" slabs, 2x6 for 5" slabs. Stake every 4 feet. Check for level and proper slope (¼" per foot away from buildings).
- Place vapor barrier and reinforcement. 6 mil poly under interior slabs. Wire mesh or rebar grid raised 1.5-2" off the base on chairs.
- Pour and screed. Pour from far end working back. Screed level with the forms using a 2x4. Don't over-work the surface.
- Float, edge, and joint. Bull float once water sheen disappears. Edge the perimeter with an edging tool. Cut control joints every 8-10 feet.
- Final finish and cure. Broom finish for traction or trowel for smooth. Cover with plastic for 7 days minimum, lightly mist daily.
- Wait before loading. Foot traffic 24-48 hours. Vehicles 7 days. Heavy equipment 28 days.
Concrete Patio Cost Breakdown
| Patio Type | Material Cost (sq ft) | Installed Cost (sq ft) | 12x16 Patio Total |
|---|---|---|---|
| Plain broom finish | $2-$4 | $6-$10 | $1,152-$1,920 |
| Stamped concrete | $8-$12 | $12-$18 | $2,304-$3,456 |
| Exposed aggregate | $4-$7 | $8-$14 | $1,536-$2,688 |
| Colored/stained | $4-$8 | $8-$15 | $1,536-$2,880 |
Patio Preparation -- What to Do Before You Pour
- Excavate 8-10 inches below finished grade. You need 4 inches of gravel base plus 4 inches of concrete. In freeze-thaw climates, use 6 inches of gravel to improve drainage and reduce frost heaving.
- Compact the subgrade. Rent a plate compactor ($60-80/day) and compact the soil in 2-inch lifts. Soft or loose soil causes settling cracks. This is the most skipped step and the most important one.
- Install 4 inches of compacted gravel base. Use crushed stone (not pea gravel) for stability. Compact it in 2-inch lifts. This base drains water away from the concrete and prevents frost heave.
- Build your forms 4 inches above the gravel. Use 2×4 lumber staked every 2 feet. Slope forms away from the house at 1/8 inch per foot for drainage (a 12-foot patio drops 1.5 inches toward the yard edge).
- Place control joints every 8-10 feet. Concrete shrinks as it cures. Control joints give it a place to crack in a straight line instead of randomly. Place them at 1/4 of the slab thickness deep.
- Add wire mesh or rebar for slabs over 200 sq ft. 6×6 welded wire mesh or #3 rebar on 18-inch centers, elevated 1.5 inches off the base with wire chairs. This won't prevent cracking but keeps cracks tight if they occur.
Patio Pour: Truck vs Short Load
| 2026 Truck | Max Payload | Concrete Capacity | Bag Capacity (80lb) |
|---|---|---|---|
| Toyota Tacoma (standard) | 1,521 lbs | ~0.38 cu yd | ~18 bags |
| Toyota Tacoma (i-FORCE MAX) | 1,705 lbs | ~0.42 cu yd | ~21 bags |
| Ford F-150 (PowerBoost Hybrid) | 1,740 lbs | ~0.43 cu yd | ~21 bags |
| Ford F-150 (5.0L V8) | 2,235 lbs | ~0.55 cu yd | ~27 bags |
| Ford F-150 (3.5L EcoBoost) | 2,440 lbs | ~0.61 cu yd | ~30 bags |
| 3/4-ton (F-250, Silverado 2500) | 3,500+ lbs | ~0.87 cu yd | ~43 bags |
*Payload values from 2026 manufacturer specs. Your actual payload is on the door-jamb sticker. Add accessories (toolbox, bedliner) and that number drops 100-300 lbs. A driver and passenger count against payload too.
If your project needs more than 1 cubic yard (4,000 lbs), pickup-truck delivery requires multiple trips. For 2+ cubic yards, ready-mix delivery is almost always cheaper than the gas, time, and suspension wear of multiple bag runs. Most ready-mix trucks deliver 8-10 yards in one trip.
Patio vs Slab: Why the Concrete Math Differs
A patio is a slab, but not every slab is a patio. The difference matters for your concrete order. Patios are decorative outdoor surfaces that need a specific PSI rating (3000-3500), air entrainment for freeze resistance, and a broom or stamped finish. Standard utility slabs skip all of that.
Patio pours also waste more concrete than garage floors or driveways because of irregular shapes. Most backyards are not perfect rectangles - you have garden beds to work around, trees with root zones, existing walkways, and grade changes. That is why we default to a 10% waste factor for patios while driveways only need 5%.
2026 cost reality from Elena S.: Stamped concrete patios run $12-$18 per square foot installed versus $6-$10 for plain broom finish. A 12x14 patio at $15/sqft stamped costs around $2,520 installed. Our calculator shows material cost only - labor typically doubles or triples the number for patios because of the decorative finishing work.
Concrete Patio FAQ
How do I calculate concrete for a patio?+
Length x width x thickness in feet, divided by 27. A 16 x 12 patio at 4 inches is 16 x 12 x 0.333 = 64 cubic feet, or 2.37 cubic yards. Add 10 percent for the dips in your subgrade and order 2.6.
How many bags of concrete for a 12x12 patio?+
A 12 x 12 patio at 4 inches needs 48 cubic feet, which is 80 bags of 80 lb before waste. That is about 1.8 cubic yards and well past the point where a ready-mix truck is both cheaper and faster.
How thick does a backyard patio need to be?+
Four inches over a compacted base handles furniture, a grill, and foot traffic. Go to five inches if a hot tub is going on it, and put the extra thickness under the tub footprint rather than the whole slab.
Does a patio need rebar or is mesh enough?+
Mesh is acceptable for a plain foot-traffic patio if it is lifted to mid-slab on chairs, not laid on the ground. Switch to number 3 or number 4 bar on an 18 inch grid if the patio carries a hot tub, an outdoor kitchen, or sits on expansive clay.
Last updated . Formulas reviewed by Joe R., Masonry Specialist, and Elena S., Civil Engineer (PE). Spotted a number that looks wrong? Report a Data Error and we will re-verify it against the source.