How many square yards in a 20x18 feet 3 inches thick
4.074 cubic yards for every foot the slab is thick.
1 cubic yard = 27 cubic feet700 square feet x 1/2 foot = 350 cubic feet = 1226/27 cubic yards(12.963 cubic yards, rounded)
Total coverage area 314.16 sq. feet. depth of 2 inches = 1.94 cu yards answer ... around 2 cu yards
Our area is 250 ft2 so 250 ft3 would cover the area with cement a foot deep. We only need 3 inches (1/4 of a foot) so we divide 250ft3 by 4 to get our answer: 62.5 cubic feet.However, the question asks for "yards of concrete" so we need to convert cubic feet into cubic yards as follows:One cubic yard = 3ft x 3ft x 3ft = 27 ft3Dividing our cubic foot answer of 62.5 by 27 we get our answer in cubic yards:62.5/27 =2.3148148 yd3 (the 148 repeats)
Apples and oranges. Without knowing how thick the 450 sq. ft. area is or how thick you want it to be you can't convert to cubic yards. A cubic yard has 27 cubic feet. One square foot 3 inches thick would be 1/4 cubic feet. 4 sq. ft. 3 inches thick would be 1 cubic foot. 450 sq. ft. 3 inches thick is 112 1/2 cubic feet or just a bit over 4 cubic yards. 450 sq. ft. 4 inches thick is 150 cubic feet or 5 1/2 cubic yards.
18x32 feet by 4 inches thick: 7.1 cubic yards. For a 6-inch slab, 10.7 cubic yards.
A 9x9 foot slab 4 inches thick requires a minimum of 1 cubic yard. If you go to 6 inches thick you will need 1.5 cubic yards.
4.074 cubic yards for every foot the slab is thick.
A minimum of 1.3 cubic yards.
It depends on the concrete company you're working with. You need 33 yards of concrete. Concrete companies deliver the stuff in full truckloads - and no, this is NOT a job for Sakrete. If you can find a company that has Oshkosh front-load mixers, you'll need three truckloads because those trucks hold 11 yards. If you can only find companies with rear-load mixers, you need 36 yards because a rear-load mixer holds 6 yards of concrete.
18 inches
Is the concrete filled with pebble or lightweight foam? This is really an impossible question. Not enough data.
1 cubic yard = 27 cubic feet700 square feet x 1/2 foot = 350 cubic feet = 1226/27 cubic yards(12.963 cubic yards, rounded)
A 12 foot by 12 foot slab would be 3.5 inches thick. It would total 1.555555 yards mathematically. It is recommended to add 5% error to the mix and round up to the nearest half yard. If you order this then order 2 yards and expect overage.
You will need a minimum of 2.42 cubic yards of cement.
A cubic foot is 12" thick 12" wide and 12" deep. .45 cubic feet per 60# bag of concrete
10.00 dollars per square foot plus permit cost.