How much concrete do you need per cubic metre?

Whenever you are undertaking a project that requires the use of multiple 20kg bags of concrete, the first question you should ask is how much do I need?

Unfortunately, due to the nature of how concrete mixes and sets, simply guessing how much is required can result in either too much or too little being used, with both scenarios not being ideal for any project.

If you end up with too much concrete, you will have to find some other use for it fairly quickly, as once it mixes, it's going to set whether you like it or not. On the other end of the spectrum, you could end up with too little concrete and have to rush back to the hardware store, buy more concrete, mix it, and hope that the original concrete you have laid hasn't begun to set itself.

How much concrete do I need?

In general, one 20kg bag of quick-set cement will be enough to fill a 10mm deep trench over an area of 1.1m2, so if you are simply covering a relatively shallow area in cement, then all you need is one bag per cubic meter, which is fairly easy to calculate.

For context, 1 cubic meter is equal to an area of 1000mm x 1000mm x 1000mm, which is quite a large area. Going off of the consensus that one 20kg bag will fill a 10mm trench, it would take nearly 100 20kg bags to fill an area of one cubic meter with cement.

How to calculate the amount of cement you need

If you are unsure of exactly how much cement you will need for your project, the best course of action would be to measure the length, width, and depth of the area you need to be filled to the closest millimetre and discuss it with your supplier.

In general, most hardware stores or commercial companies that supply quick-set cement will be able to give you a general idea of how many bags you will need for your particular project, though there are other ways of calculating it if, for some reason, they aren't able to help.

There are many websites that are designed to calculate your concrete needs by taking the measurements into account, such as Concrete Calculator. Websites like these should be taken with a grain of salt, however, as they don't take into account the specifications required for certain projects, such as the depth of a driveway or the width of a fence post hole.

Where you can find the required specifications

In general, if you are hiring someone to do your project for you, they should, in theory, know what they are doing and will account for the amount of cement you need accordingly.

However, if you are undertaking a project yourself, you will need to find out the exact specifications required. 

Find out more or buy concrete and cement online

If you need a supplier of cement mix, concrete and other building supplies, get in touch with Jaybro today for fast delivery and great prices.