One thing I get asked a lot during my time working as the head of content at a huge tile retailer is ‘how do I work out how many square metres my wall is?’ or ‘how many square feet is my floor?’
I thought I’d create a very quick blog post to explain this, since it’s such a simple sum, and yet so many people seem to get stuck on it!
1) Choose Your Units
Firstly, It’s important to know which unit of measurement you need to know to make things easy when it comes to buying your material. Some decorating materials are sold by the square metre (sqm) such as tiles and some are sold by the square foot (sqft), such as some artificial grass I bought recently.
Double check which unit of measurement you’d like to calculate your surfaces in. There are two main ones:
Metric, which is metres (m) and centimeters (cm), and Imperial, which is feet (ft) and inches (in).
2) Measure the height and width of your surface
Next up, it’s time to get measuring! Get your tape measure out.
Firstly, measure the surface (whether it’s a wall or floor) from top to bottom. Make sure you take your reading in the right unit – metric or imperial. Writing down your measurements will make it easier. Next, measure the surface from left to right!
Note: Every cm is a 100th of a metre, so a distance of 1 metre and 34 centimetres equals 1.34 metres.
Now, times the measurements together. For example, if you’re measuring in metres, and your surface is 5.6m x 4.2m, the surface area is 23.52 Sqm (square metres).
Repeat this for all the surfaces you’re working on, and then add up the Sqm at the end!
3) Add a little extra
Usually, no matter what decorating material you’re using, you’re never going to only require the exact surface area. With tiles, laminate, vinyl, etc, you’ll likely need some excess for cut pieces and wastage. It also never hurts to keep some spare pieces in the shed in case you ever need spares, so we recommend adding 10% onto the square metreage.
If you’re buying paint, consider the amount of coats you’ll need. If it’s 2 or 3 coats, you’ll need to times the surface area by 2 or 3 when factoring in how many coats you’ll need. Emulsion roughly covers 12 Sqm per coat per litre, although it varies.
Check out our painting guide: How to paint without making a mess of it
Extra note: Factoring in windows and doors
If you’re painting a wall with a huge window or door in the middle of it, that’s worth factoring into your square metre total!
To do this, simply treat the window or door as it’s own surface and calculate its surface area using the same process as above! Then, subtract it from the total Sqm of the wall space! Easy.
There you have it – how to measure your room.