Top Tip
Always round up to ensure that you have enough paint to complete the job.
DIY Interiors

How much paint do I need?
Use the easy steps below to determine the right amount of paint to purchase.
Step One: The Perimeter
Measure the perimeter of your room (length and width, in metres). Add all 4 numbers together.
Length + Length + Width + Width = Total Perimeter (m)
Step Two: The Height
Multiply the perimeter by the height.
Total Perimeter x Height = Gross Area (m²)
Step Three: Doors & Windows
Deduct windows and doors. An average window is approximately 1.5 m² and an average door is 2.5m².
Gross Area(m²) - Doors & Windows (m²) = Total Area (m²)
Step Four: Paint Loss Compensation
To compensate for minimal paint loss, divide Total area by 14
Total Area(m²) / 14 = Number of Litres required per coat
The table below is a guide to the number of litres required per coat. Actual usage will vary depending on application technique, surface texture and porosity.
Wall Dimensions - distance in metres around the room | |||||||
---|---|---|---|---|---|---|---|
Wall height (m) | 10m | 12m | 14m | 16m | 18m | 20m | 22m |
4.0m | 2.5L | 3.0L | 3.5L | 4.0L | 4.5L | 5.0L | 5.5L |
3.7m | 2.5L | 3.0L | 3.5L | 3.5L | 4.0L | 4.5L | 5.0L |
3.4m | 2.0L | 2.5L | 3.0L | 3.5L | 4.0L | 4.5L | 4.5L |
3.1m | 2.0L | 2.5L | 3.0L | 3.0L | 3.5L | 4.0L | 4.5L |
2.8m | 2.0L | 2.0L | 2.5L | 3.0L | 3.0L | 3.5L | 4.0L |
2.5m | 1.5L | 2.0L | 2.5L | 3.0L | 3.0L | 3.5L | 3.5L |
2.2m | 1.5L | 2.0L | 2.0L | 2.5L | 2.5L | 3.0L | 3.5L |
Decide on Water based or Oil based Paint
Today's water based paints perform just as well as oil based products!
Water based paints are better for our environment, more convenient as they are low in odour, faster drying, easy to use and wash up in water. Some, such as Pascol TRIM Water Based, have better exterior durability than oil based enamels.
Keep reading...
Step 1: How much paint do I need?
Step 2: Which sheen should I use?
Step 3: Choosing the right Prep Coat
Step 5: Let's paint Ceilings and Walls
Step 6: Let's paint Trims and Woodwork
Step 7: Which tools do I need?
Step 8: Clean-up, storage & disposal
Guide Download
Download a PDF of our DIY Exterior Painting Guide