How do I work out wall area for painting?

Add the width of every wall in the room to get one number, then times it by the ceiling height. That gives the whole wall area. Then take off the doors and windows.

Should I subtract doors and windows?

Yes, and use the real sizes. In a small bedroom it makes little difference. In a villa with sliding doors it can save you a whole gallon of paint.

How much paint for a 12 by 12 room?

A room about 3.6 m by 3.6 m with 3 m walls has roughly 43 square metres of wall. Less a door and a window, two coats needs about 7 litres.

Can I use the same paint on walls and ceiling?

You can, but most people do not. Ceilings are usually done in a flat white ceiling paint, which hides bumps better and costs less than a coloured wall paint.

What if my walls are textured?

Add about a third more paint. A textured surface has more actual area than its flat measurement, so it takes more to cover.

Does this work for outside walls too?

The area sum is the same, but exterior paint covers less per litre. Change the coverage number to what your exterior tin says, or use the interior versus exterior calculator.

Wall Paint Calculator

All walls added up

Walk round the room and add the width of every wall.

Wall height

Coats

Doors

One door width

One door height

Windows

One window width

One window height

Coverage per litre

m2/L

Written on the tin. Most wall paints say 10 to 12.

Tin size

Your answer

Wall paint you need

9 litres

Buy 3 at 3.6 litres each.

Wall area before openings: 54 m2
Doors taken off: 1.9 m2
Windows taken off: 2.9 m2
Wall area to paint: 49.2 m2
Paint per coat: 4.5 L

This is walls only. For the ceiling as well, use the paint calculator or the ceiling paint calculator.

Wall Paint Calculator for Dubai and the UAE

This tool works out paint for walls only. No ceiling. You give it the size of the walls, then the real size of your doors and windows, and it tells you the litres and the tins.

It asks for real sizes because in the UAE they are often not normal. A villa can have a window that runs the whole length of a wall, and a sliding door to a balcony is far bigger than a bedroom door.

If you take off a standard size when the real thing is twice that, you buy paint you do not need.

How to measure your walls

The easy way is to walk around the room with a tape measure and add up the width of each wall as you go.

Add the walls together
Measure wall one, wall two, wall three, wall four. Add them all into one number. That is the number the tool asks for first.
Measure the height once
Floor to ceiling. Do it in one corner. It is the same all round in almost every flat.
Measure one door and one window
If they are all about the same, measure one of each and put in how many there are.
Odd shapes
A room with a jog in it is still just walls. Measure each straight part and add them.

Why openings matter more here than you think

In a small bedroom a door and a window take off about four square metres. That is small. You could ignore it.

In a Dubai villa living room it is a different story. A sliding balcony door can be 2.4 m wide and 2.4 m tall. That is nearly six square metres on its own. Two of those and a wide window and you have taken fifteen square metres off the wall.

Fifteen square metres over two coats is nearly three litres of paint. That is most of a gallon you did not need to buy.

It works the other way too. If you guess that your window is small when it is large, you order too much. Measuring takes two minutes.

What kind of paint goes on walls

For inside walls, most homes use an emulsion, sometimes called a wall paint or a latex paint. It is water based, it dries fast, and it does not smell much.

There is a choice of finish inside that. Matt hides bumps well but marks easily. Silk and satin wipe clean, which is why they go in hallways and kids rooms. Gloss is for wood and metal, not for walls.

Coverage changes with the finish. A matt paint usually covers a bit more per litre than a silk. The tin will tell you, and the tool lets you change the number.

Bathrooms and kitchens want a paint made for damp rooms. It costs a little more and it stops the black spots that come back every year.

What the sum cannot see

Two walls of the same size can need different amounts of paint. Here is why.

The colour underneath
Painting cream over cream is easy. Painting cream over dark grey takes an extra coat, and sometimes a coat of white in between.
How the wall was finished
A wall smoothed with putty and sealed takes paint evenly. A bare or patchy wall drinks it in some places and not others.
Filled cracks
Filler is thirsty. Every repaired patch will show through the first coat unless it was primed first.
The paint itself
Thick, good quality paint covers in two coats. Thin paint looks the same in the tin and needs three.

Buying paint in Dubai

Paint here is sold by the litre, the 3.6 litre gallon and the 18 litre drum. For one room the gallon is usually the right size.

Buy all your paint at the same time. Tins made in different batches can be very slightly different in colour, and on a big wall you can see the join.

Ask the shop to write the colour code on the receipt, or take a photo of the tin label. In two years, when you want to touch up a mark, that code is the difference between a five minute job and repainting the whole wall.

If a painter is doing the work, the paint should be bought in your name and the leftover tins left with you at the end.

Questions people ask

How do I work out wall area for painting?: Add the width of every wall in the room to get one number, then times it by the ceiling height. That gives the whole wall area. Then take off the doors and windows.
Should I subtract doors and windows?: Yes, and use the real sizes. In a small bedroom it makes little difference. In a villa with sliding doors it can save you a whole gallon of paint.
How much paint for a 12 by 12 room?: A room about 3.6 m by 3.6 m with 3 m walls has roughly 43 square metres of wall. Less a door and a window, two coats needs about 7 litres.
Can I use the same paint on walls and ceiling?: You can, but most people do not. Ceilings are usually done in a flat white ceiling paint, which hides bumps better and costs less than a coloured wall paint.
What if my walls are textured?: Add about a third more paint. A textured surface has more actual area than its flat measurement, so it takes more to cover.
Does this work for outside walls too?: The area sum is the same, but exterior paint covers less per litre. Change the coverage number to what your exterior tin says, or use the interior versus exterior calculator.

Need the job done

We do this work across Dubai

Use the numbers above to plan, then let us quote the real thing.

Call +971 54 381 1897 WhatsApp Us

More tools

Other calculators worth a look

See all tools