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Units
Shape
Slab: what to measureA drawing of the shape marking the length, width, and thickness.LengthWidthThicknessSide view of the slab4 in of concrete with no gravel base.Concrete 4 in
ft
ft

4 in (10 cm) is typical for patios and walkways.

in

The ready-mix industry recommends 4% to 10% extra for spills and uneven ground.

%
Gravel base (optional)
Gravel base (optional)

The compacted layer of gravel or crushed stone under the concrete. Leave the depth empty for no base.

The depth once compacted.

in

Gravel shrinks 20% or more when compacted (FHWA).

%
$per ton
Material cost (optional)
Material cost (optional)

Enter your local prices to see what the order costs. Prices vary by area and supplier.

Bag size you are pricing

Delivered, from your local supplier.

$per yd³
$

Concrete to order

1.36 yd³

1.23 yd³ for the shape, plus 10% extra.

Concrete to order. 1.36 yd³. 1.23 yd³ for the shape, plus 10% extra.

What to buy
Cubic yards1.36
Cubic feet36.67
80 lb bags62
60 lb bags82
40 lb bags123
Ready-mix truckloads1

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