Answer

Estimated Concrete Volume

6 cubic yards

162 cubic feet

Estimated Weight of Concrete

## 10.77 tons

Covering 324 sq. ft. at 6" depthChange dimensions

Optional 10% extra concrete

for waste allowance

10% = 0.6 cubic yards

Total Concrete with 10% = 6.6 cubic yards

for waste allowance

10% = 0.6 cubic yards

Total Concrete with 10% = 6.6 cubic yards

## Order Size

This order size is considered

**Large**### How Many Concrete Bags?*

359 | 60lb Concrete bags |

270 | 80lb Concrete bags |

81 | Small wheelbarrow loads |

40.5 | Large wheelbarrow loads |

## Concrete Truck for 18'x18' x6"

60%

**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****$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

4 x $17.00 = $68.00

$649.32 + $68.00 =

*6 inch pours and under.

**Cost assumes subbase and general prep is done.

**$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.

4 x $17.00 = $68.00

$649.32 + $68.00 =

**$717.32****$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.

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/m

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/m

^{3}or 133 lbs/ft^{3}.## 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'

*x*18'

*x*6", 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.