To perform a concrete take off, all you need are some simple math skills.
Concrete is sold by the Cubic Yard (CY)so you will need to convert your total desired area from Square feet (SF) into CY.
To find cubic Feet you will multiply (Lenght x width) x (thickness in inches/12) = cubic feet
once you have your cubic feet you will need to divide by 27 because there are 27 cubic feet in one cubic yard.
If your slab was 30'x 30' here is how the calculation would work.
30' x 30' x (4/12) = 300 CF
300 CF / 27 = 11.11 CY
you would order 12 yards and that should account for waste
ponypomp--
There are concrete calculators online, the calc for your job works out to
11,11 yards. Here is one online calc for you.
The above post is correct, you would ask for 12yards.
http://www.concretenetwork.com/concrete/howmuch/calculator.htm
10 yards
6.67 Cubic Yards
To calculate the volume of concrete needed, first convert the dimensions to feet: a 30x30 area is 30 feet by 30 feet, and 4 inches is 1/3 of a foot. The volume in cubic feet is 30 x 30 x (1/3) = 300 cubic feet. To convert cubic feet to cubic yards, divide by 27 (since there are 27 cubic feet in a cubic yard): 300 ÷ 27 ≈ 11.11 cubic yards. Therefore, you need approximately 11.11 yards of concrete.
If it is 4 inches deep/thick, 2 cubic yards. If it is 6 inches deep/thick, 3 cubic yards.
39.1116 cubic yards
10 yards
6.67 Cubic Yards
If it is 4 inches deep/thick, 2 cubic yards. If it is 6 inches deep/thick, 3 cubic yards.
39.1116 cubic yards
15 cubic yards
15 cubic yards
How many square yards in a 20x18 feet 3 inches thick
Depends on how thick it is. At 4 inches thick, you would nee about 5.5 cubic yards adjusting for safety. At 6 inches, you'd need about 8 cubic yards. You can play with different thicknesses with the linked concrete pad calculator.
8.25 cubic yards of concrete
Okay first dont go 3 inches thick ... it will crack it's to thin 3.5 " to 4" thick is the min. and it'll take 2.777 yards so you'll have to get 3 yards
90 sq yds at 4" thick.
one (1) cubic yard of concrete four inches thick will cover 80 sq. feet. 85 yards x 81 = 6885 sq. feet.