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Length imperial. Weight lb. Currency USD. Weight uses 1 lb = 0.45359237 kg. Currency converts US-dollar planning prices and does not change volumes, counts, or geometry.

24×24 Slab at 6 Inches: Rebar, Bags, and Truck

A 24 by 24 ft pad at 6 in, with the thickness table repeating the takeoff at the other standard depths.

Formula SSC-2026.1

Formula SSC-2026.1 · 4,000 PSI

Order volume

11.73 yd³

8.971 m³ placed+waste

Order weight

47,520 lb

21,555 kg

80 lb bags

528

13 pallets at 42 bags

60 lb bags

704

0.45 ft³ yield each

Rebar

816.00 ft

68 × 20 ft · 68 × 6 m · 600 lb

Ready-mix vs bags

$1,936.00

Truck $1,936.00 · 80 lb bags $3,564.00

Slab footprint and rebar gridLive scaled blueprint
24.00 ft24.00 ft#4 / 12 mm at 18 in OC · 6 in slab

Grid lines are equalized so the drawing stays readable. The order count uses on-center spacing with a bar at each end of the layout, then holds concrete cover in the field.

Bill of materials and shopping list
ItemNetWasteOrderUnit priceLine total
Ready-mix concrete10.67 yd³10%11.73 yd³ / 8.971 m³USD$1,936.00
Short-load feeFull load—2 truck @ 10 yd³USD$0.00
80 lb pre-mix bags480.0 bags10%528 bagsUSD$3,564.00
60 lb pre-mix bags640.0 bags10%704 bagsUSD$3,801.60
#4 rebar sticks, 20 ft68 sticks10%75 sticks / 68 × 6 mUSD$1,050.00
Rebar chairs289 crossings10%318 chairsUSD$89.04
Tie wire rolls289 ties10%2 rollsUSD$16.00

Ready-mix truck

$1,936.00

1.17 nominal 10 yd³ loads · 2 to order

80 lb bags

$3,564.00

60 lb alternative $3,801.60 · delivery weight 47,520 lb

Side-by-side thickness comparison at the same footprint
ThicknessOrder yd³Order m³80 lb bagsRebar ftReady-mix80 lb cost
4 in7.825.981352898$1,290.67$2,376.00
5 in9.787.476440898$1,613.33$2,970.00
6 in11.738.971528898$1,936.00$3,564.00
Show the deterministic formula

Slab ft³ = L × W × thickness ÷ 12. Thickened-edge extra = footing band × (footing depth − slab thickness), with corner squares counted once.

yd³ = ft³ ÷ 27. m³ = ft³ × 0.0283168. Weight uses 150 lb/ft³, then the header converts that pound total at 1 lb = 0.45359237 kg. 80 lb bags yield 0.6 ft³ and 60 lb bags yield 0.45 ft³. Currency changes the price labels only.

Bars across a span = floor(span ÷ spacing) + 1. Order sticks = that count, plus 10, 5, or 15 percent waste, cut from 20 ft and 6 m stock. Chairs = one per grid intersection.

Engineering notes

A 24 by 24 ft rectangle at 6 in is about 10.67 cubic yards before waste. This page adds 10 percent waste, prices 4,000 PSI ready-mix against 80 lb and 60 lb bags, and lays #4 bar at 18 in on center. The comparison table repeats the same footprint at 4, 5, and 6 in so the extra inch of thickness is only extra volume, not a different grid. Soil bearing, vapor retarder, and joints are not designed here.

Code reference

IRC R506.1 sets a 3.5 in minimum for concrete slab-on-ground floors. Reinforcement cover and spacing follow ACI 318 practice and the local inspector. This quantity takeoff is not a soils or structural design.

Field questions

How many cubic yards is a 24 by 24 slab at 6 in before waste?
Length times width times thickness in feet, divided by 27, is about 10.67 cubic yards. The order line then applies the waste factor on the page.
Does the rebar count change when the slab gets thicker?
No. The grid follows the length, width, and spacing. Thickness changes volume, weight, bags, and the ready-mix price.
When is a truck cheaper than bags?
Compare the ready-mix line, including any short-load fee under 4 yards, with the 80 lb bag line. Both use the prices typed on the page.

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