Less waste. Less cost. Perfect results.
Calculate the paint or wallpaper you need, including coats, pattern repeat and a sensible waste allowance.
Enter the room size and total area of doors and windows.
Estimate only. Check manufacturer guidance before purchasing.
UNDERSTAND THE TOOL
Decorating estimates are mostly a geometry problem: calculate the wall area, allow for doors and windows where appropriate, then translate the remaining area into paint coverage or wallpaper rolls. A sensible waste allowance protects against small measuring errors and cutting losses.
Decortastic uses the room dimensions you enter to estimate the surface area to cover. Paint calculations depend on the stated coverage of the product and number of coats. Wallpaper estimates also depend on roll dimensions and can be affected by pattern repeat.
The result is an estimate, not a substitute for the manufacturer’s instructions. Rough or porous walls can use more paint, and large repeating wallpaper patterns can create more offcut waste than plain paper.
A 4 m by 3 m room with 2.4 m-high walls has a gross wall area of 33.6 m² before allowing for openings. Two coats of paint require coverage for roughly twice the paintable area, so the coverage figure on the tin matters.
Usually yes for a close estimate, although leaving small openings in the total can provide a useful waste allowance.
Matching a repeated design can require extra length on each drop, increasing the number of rolls needed.
Two coats are common, but new plaster, strong colour changes and some finishes may need primer or additional coats.
