How to work out how many tiles to buy?

Working out how many tiles you need to complete your project isn’t a straightforward task. Here, we’ll help you work out exactly how many tiles to buy for your project.

Working out how many tiles you need to complete your project isn’t a straightforward task. Not only will you have to calculate the surface area of both the surface you wish to tile and the individual tiles you’re looking to use, but you’ll also have to consider the layout of your tiles. After all, if you lay them diagonally, you’ll end up using more tiles than if you lay them straight.

If this has got your head in a spin, don’t panic! This answer will help you work out exactly how many tiles to buy for your project.

How to work out how many tiles to buy in 3 quick steps

Ready to calculate how many tiles to buy? Simply follow these 3 simple steps.

1. Measure your walls or floors

First things first, you’ll need to measure the area that you wish to tile.

If your room is square or rectangular, you’re in luck! This is the simplest shape to measure. You can just measure the length and width of the surface you want to tile and multiply them together.

For example, if you want to tile a bathroom floor that's 2.5m long and 2m wide, you’ll have a surface area of 5m2 (2.5 x 2 = 5).

If your room is an irregular shape or there are obstacles in the way that don’t need tiling, don’t worry. In this case, you’ll just need to split your room into several rectangular-shaped segments. Work out the surface area of each segment and then add them together.

Let’s say that your room is L-shaped. To work out the total area, you can split it into two rectangles.

You might have one rectangle that’s 1m long and 2m wide, and another rectangle that’s 1.5m long and 2m wide. The first area would be 1m2 (1 x 2 = 2), while the second area would be 3m2 (1.5 x 2 = 3).

Add the two areas together and you’ll find that the total surface area is again 5m2 (2 + 3 = 5).

2. Add wastage

It’s important to order more tiles than you think you need. This is because tiles will be cut to fit the space, and you may also get breakages and mistakes occurring.

If this happens, it’s important to have replacement tiles on hand that you can draw on. Plus, it can be handy to have some tiles leftover at the end of a project so that if anything happens (for example, you drop something heavy on your new tiled floor), you can replace broken tiles with ones from the same batch.

As a general rule, it’s recommended that you add in 10% wastage to your tiling project. So, if the total area that you want to tile is 5m2, you’ll want to get enough tiles to cover 5.5m2 (10% of 5 is 0.5, add that to 5 and you get 5.5).

However, if you’re hoping to lay your tiles diagonally (by which we mean at 45 degrees), or you’re tiling around obstacles that are going to result in more wastage, it’s safest to add 15% wastage instead of 10%.

In this case, if your surface area is 5m2, you’ll want to get enough tiles to cover 5.75m2 (15% of 5 is 0.75, add that to 5 and you get 5.75).

3. Check the coverage of one box of tiles

Once you’ve chosen the tiles you want to use, you’ll need to check the coverage of the box.

Tiles vary massively in size, so it’s not the number of tiles in a box that’s important – rather, it’s the number of square metres that the box of tiles will cover in total that you’ll need to focus on.

Many tile boxes will have a helpful chart on the packaging showing you how many boxes you’ll need to cover rooms of various sizes. However, if your box doesn’t have a chart like this, you can work it out yourself.

Simply take the total area of the surface you want to tile, and divide it by the total square metre coverage of the box.

So, if the surface you want to tile is 5.5m2 (including wastage) and one box of the tiles you want to use covers 1m2, you’ll need to divide 5.5 by 1. A quick bit of maths and it’s clear that you’ll need to buy 6 boxes (5.5 ÷ 1 = 5.5) – unless your tiles are available to purchase in half boxes, of course!

Get the help of a professional

If all this maths is making your brain hurt – or you don’t have the time to manage your tiling project yourself – why not get the help of a professional tiler?

A professional tiler will be able to help you calculate exactly how many tiles you need to cover your space. Plus, they’ll be able to complete your entire tiling project for you, guaranteeing that your job will be completed to a professional standard you can be proud of.

Our guide to tiling costs has more information.

Need some tile ideas for your room?

We've got several ideas guides to help you with any home improvement project. One of which is tiling.

Bathroom, kitchen, living room, wherever you need tiling, you can do achieve all kinds of looks. Make sure to check out some of these tiling ideas:

• Bathroom tiling ideas

• Small bathroom tile ideas

• Shower tile ideas

• Kitchen tile ideas

• Kitchen floor tile ideas

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