*
The number one concern that we gain on our hotline (1-866-lifwynnfoundation.org) is, “how lot concrete execute I need”? but let’s challenge it, uneven you have a practical real people application because that those boring mathematics problems, you just don’t care enough to retain it. Well, currently you do have actually a real human being application so let’s go v the exercise so you will know exactly how to do it there is no calling the following time. You can even impress your friends in ~ dinner next (if the subject around concrete should occur to come up). I would just recommend this topic for those ”friends” whereby you nothing mind if you were never ever invited back to again.

You are watching: How much does one cubic foot of concrete weigh

For those who are an ext direct, and want the short cut answer please scroll to web links at the end of this blog.

How come Calculate how Much Concrete i Need

The an initial thing you have to do is relax. It really ain’t that hard. Nothing let terms like “cubic feet” and “yield” and “density” stroked nerves you. There space basically two steps. The first step is figuring the volume that the room you want to fill. It no make any type of difference if you want to to fill it with concrete or vanilla ice cream. Volume is volume. Since of the amount of concrete essential for most work it is usually easiest to number the volume in cubic feet. If your job is big enough to calculate the volume in cubic yards instead of feet, call a prepared mix concrete truck. As soon as you listen “cubic” think ice cream cube. An ice cube usually has actually three sides (at the very least the ones you make in the trays in your freezer at home do). The means to discover the volume of a cube is to multiple all 3 sides. If your cube to be a perfect cube and also it was 2 feet large and 2 feet long and also 2 feet deep, the volume would be 8 cubic feet. Concrete slabs room usually no perfect cubes for this reason the mathematics is a tiny different. If you to be going to pour a slab the was 2 feet broad and 2 feet lengthy it would certainly not likely be 2 feet deep. It could be 4” deep i beg your pardon is a normal depth because that a concrete slab. So now the equation looks choose this: 2’ x 2’x 4”. The difficulty is you have to get every little thing into the exact same units; you can not multiple feet through inches. This is wherein folks gain hung up however it’s actually fairly easy. Just multiple 2 x 2 x 4 ÷ 12. The answer is 1.3 cubic feet.

If you space filling a ring hole in the soil to set a post or mail box, the calculation for volume is various than a cube or rectangle. The formula for the volume of a ring hole is pi r2 x depth. Or 3.14 x radius x radius x depth. The radius is half the width of the hole. Uneven you room doing a monster hole it could be easiest to carry out this all in inches. If your hole is 36” deep and also 10” wide, the calculation is 3.14 x 5 x 5 x 36 ÷ 1728. This offers you 1.6 cubic feet. If girlfriend forget the 1728 that is just 12” x 12” x 12” or the number of cubic customs in a cubic foot.

So currently that we recognize the volume the 2nd step is to calculation how numerous bags the concrete it will take to fill the hole. Top top the bag it will tell friend how countless cubic feet the bag will fill. This is the “yield”. The productivity on an 80 lb bag is about 6/10 (.6) cubic feet. If you take the example above of 1.6 cubic feet, the calculation would be :

1.6 ÷ .6. = 2.7 bags

If you take place to be enthralled v math calculations I administer the complying with information on exactly how to calculate the yield the I said was .6 cubic feet for an 80 lb bag. The an initial thing you require to recognize is the “density” the the concrete. If I provide you a box filled v concrete that steps 12” x 12” x 12” (or 1 cubic foot), exactly how much execute you think it will weight? walk ahead and also take a guess- almost everyone it s okay it wrong. The price is 145 lbs. (If it was filled with beer it would weigh 64 lbs.) This way the “density” that concrete is around 145 lbs per cubic foot. Currently that we have that details we deserve to calculate the yield. Include up both the dry material in the bag (80 lbs) and the water that takes come mix it increase (1 gallon which weighs 8.3 lbs) because that a full weight of 88.3 lbs. Then division the total weight by the density of the concrete.

88 ÷ 145 = .60 cubic feet.

See more: How To Factory Reset Compaq Computer, How To Reset A Compaq Computer

There is one an approach for calculating the variety of bags required which is also easier. We have already done the mathematics for you on concrete as well as a variety of other products. Visit our calculators page prior to your next project. Determine exactly how much you require from home, the keep aisle or from the jobsite.