Tampa concrete slab calculator
Type in the slab size and the numbers below recalculate.
- Slab area
- 400 sq ft
- Concrete to order
- 5.43 cu yd
- 4.94 cu yd net, plus 10%
- Installed at HomeBlue's Tampa rate
- $2,400 to $4,400
- Installed at projectcosted's Tampa rate
- $2,220 to $4,436
- Ready-mix only (no labor, base, steel or delivery)
- $636 to $760
The two installed figures multiply your area by HomeBlue's Tampa reinforced-slab range ($6 to $11 per sq ft, September 2024) and projectcosted's Tampa range ($5.55 to $11.09 per sq ft, August 2026). Ready-mix uses HomeBlue's Tampa price of $117 to $140 per cubic yard. Use it to budget; a quote for your lot replaces it.
Nothing you type is saved or sent anywhere. For an L-shaped patio or a slab with a bump-out, split it into rectangles, run each, and add the results together.
The math behind the concrete slab calculator
Ready-mix is ordered in cubic yards, and a cubic yard is 27 cubic feet. The calculator converts inches of thickness to feet, multiplies out the volume and divides by 27.
Where the price figures come from
The two installed ranges multiply your area by each source's per-square-foot figure for Tampa, so they include labor, base and finishing the way each source defines them. On projectcosted's 400 square foot Tampa example, labor is 50 percent of the job, materials 36, site prep and equipment 8 and overhead 6. The ready-mix line is concrete only, at HomeBlue's $117 to $140 a yard.
Yards of concrete for common Tampa slabs
These are the sizes that come up most in Tampa backyards and driveways, worked at 4 and 6 inches. Net volume, so add your waste allowance.
| Slab | Area | At 4 in | At 6 in |
|---|---|---|---|
| 4x4 AC pad | 16 sq ft | 0.20 cu yd | 0.30 cu yd |
| 10x12 shed pad | 120 sq ft | 1.48 cu yd | 2.22 cu yd |
| 12x16 shed pad | 192 sq ft | 2.37 cu yd | 3.56 cu yd |
| 20x20 patio | 400 sq ft | 4.94 cu yd | 7.41 cu yd |
| 12x40 RV pad | 480 sq ft | 5.93 cu yd | 8.89 cu yd |
| 30x40 shop | 1,200 sq ft | 14.81 cu yd | 22.22 cu yd |
Swipe the table sideways to see every column →
Computed as area x thickness / 12 / 27. Edges, beams and footings are extra.
Choosing the thickness to type in
Florida's residential code sets 3.5 inches as the floor-slab minimum. HomeBlue's Tampa page puts typical residential slabs at 4 to 6 inches. Bullfrog Spas wants at least 4 inches under a hot tub and 6 or more under a swim spa, and steel building supplier MBMI describes 4 to 6 inch shop floors, 6 to 8 with heavy equipment. The thickness and rebar guide goes through each use.
What the number leaves out
A calculator can't see your lot. Tearing out an old slab ($1.10 to $1.80 per square foot on HomeBlue's Tampa page), a pump to reach a fenced backyard, extra fill on a low lot, engineered anchors for a shed or carport, and a soil check in Sinkhole Alley all land on top. So can a weather day: from late May to early October, the afternoon storm cycle pushes pours into the morning, explained in pouring concrete in Tampa rain. The Tampa slab cost page lists each add-on.