Concrete Report: 18'x18'x6"


Estimated Concrete Volume
6 cubic yards
162 cubic feet

Estimated Weight of Concrete

10.77 tons

Covering 324 sq. ft. at 6" depth
Change dimensions

Optional 10% extra concrete
for waste allowance

10% = 0.6 cubic yards
Total Concrete with 10% = 6.6 cubic yards

Order Size

This order size is considered

How Many Concrete Bags?*

35960lb Concrete bags
27080lb Concrete bags
81Small wheelbarrow loads
40.5Large wheelbarrow loads
*Approximation Estimate

Concrete Truck for 18'x18' x6"

0.6 Concrete Truck Loads (10 cu/yd Capacity)

Cost Estimate for 18'x18' x6"

Purchasing ready-mix concrete is by far the easiest way to mix concrete for medium to large projects and can even be used on smaller projects as well. We have provided a cost comparison between ready mix and DIY concrete premix bags to give you a rough ballpark estimate.

Bag Cost Estimate

Pre-mixed concrete bags cost on average $3.50 per 80lb bag. Using pre-mixed bags to cover 324 sq ft at a depth of 6", the estimated cost is $945.00
for 270 x 80lb bags

Truck Cost Estimate

Ready-mixed concrete costs on average $108.22 per cubic yard delivered. Using a concrete truck to cover 324 sq ft at a depth of 6", the estimated cost is $649.32

Concrete trucks may also charge a "short load" fee for partially filled loads. Short load fees are charged at about $17 for every yard not used on the truck.

So for a 10 cu/yd Truck Load - 6 cu/yd concrete = 4
4 x $17.00 = $68.00
$649.32 + $68.00 = $717.32

Pros Do Everything*

$1,620.00$5.00 sq ft Low End**
$1,944.00$6.00 sq ft
$2,268.00$7.00 sq ft
$2,592.00$8.00 sq ft
$3,402.00$10.50 sq ft High End***

*6 inch pours and under.
**Cost assumes subbase and general prep is done.

Concrete Extras

A well-compacted subbase provides a strong foundation for concrete to lay on. We recommend you contact your nearest concrete supplier for their recommendations on whether you need a subbase, base depth, and rock type.

With a brief look, a 18x18 area at 6 inches deep, you would need approximately 8.52 tons or 6 cubic yards of gravel.

Concrete reinforcing is also recommended in high traffic areas and medium to large areas. Wire mesh on average costs $0.56 per sq ft and fiber mesh costs $0.13 per sq ft.

So for your 324 sq ft area, this may roughly cost $181.44 for wire mesh, $972.00 for thicker wire rebar mesh and $42.12 for fiber mesh.

*Reinforcing for 10 inch pours and under.
How to Calculate Concrete Amount for 18x18 x6"
18 * 18 = 324 sq ft
6 / 12 = 0.5 ft depth
324 * 0.5 = 162 cu ft
162 / 27 = 6
= 6 cu/yd
How to Calculate Concrete Weight
6 * 3590 = 21540 lbs
Density of concrete used 2130 kg/m3or 133 lbs/ft3.

18 ft x 18 ft x 6" Concrete Summary

How much concrete do I need for an area of 18 ft x 18 ft x 6" depth? 6 cu. yds.
How many concrete bags would I need for a 18 ft x 18 ft x 6" slab? 270 x 80lb Concrete bags.
How much does it cost to pour a 18'x18' x6" slab? Ready-mix costs approx $717.32.
How much does it cost to hire a contractor to concrete a 18'x18' x6" slab? A pro costs between $1,620.00 and $3,402.00.
How do you calculate concrete volume? Formula ((width x length) x (depth in inches / 12)) / 27 = total cubic yards. See our how to here

This Page is Calculated for the Following: 18 ft x 18 ft x 6", 18x18x6, 324 sq. ft., 18 x 18, 18x18, 18x18 x6", 18'x18'x6", 18'x18' x6"
This Concrete calculator can be used for a slab, floor, garage, block, wall, driveway, patio, countertop, footings, foundation, pool or basement, and most rectangular areas.
Share this page
Disclaimer: All calculators, tools, and results featured on are to be finalized and not be considered a quotation or binding contract.
Proofs and formulas are provided as references.