Room Paintable Area Calculator

Your room

Measure the floor and the wall height in metres. A standard Australian ceiling is 2.4m.

Room sizeLength, width and wall height in metres
DoorsDoorways and openings to deduct
WindowsGlazed openings to deduct
CeilingCeilings take a different product to the walls

Trim

Skirting and architrave are measured as linear metres, then converted to a painted area using their developed girth.

Skirting boardsRoom perimeter at 0.15m developed girth
Door architrave5.1 linear metres per door set at 0.07m girth
CorniceCut in with the ceiling coat, so it adds no separate area

Coats and coverage

Defaults follow Australian trade practice. Change any figure if your tin states something different.

CoatsApplied to walls, ceiling and trim
Wall substrateBare plasterboard soaks up the first coat
Door opening areaDefault 2.04m x 0.82m, which is 1.67 m2
Window opening areaDefault 1.2m x 1.5m, which is 1.8 m2
Wall spread rate, sealedm2 per litre per coat, low sheen acrylic
Wall spread rate, first coat on bare boardm2 per litre
Ceiling spread ratem2 per litre per coat, flat acrylic
Trim spread ratem2 per litre per coat, water based enamel
Total paintable area
Enter your room size

Walls, ceiling and trim

Three separate figures, because they take three different products.

Your measured areas will appear here.
Get a painter's quote Call 1300 044 206
What this calculator assumes
  • Wall area is 2 x (length + width) x height, so it suits a rectangular room. Add each section separately for an L shaped room.
  • A door opening is deducted at 2.04m x 0.82m, which is 1.67 m2. A window is deducted at 1.2m x 1.5m, which is 1.8 m2. Both are editable.
  • Skirting is the room perimeter at 0.15m developed girth. Architrave is 5.1 linear metres per door set at 0.07m girth.
  • Cornice is cut in with the ceiling coat using ceiling paint, so it adds no separate area to the figures.
  • Spread rates default to sealed plasterboard 16, bare plasterboard first coat 11, ceiling flat acrylic 14 and trim enamel 16 m2 per litre per coat. Change them to match your tin.
  • Tins are rounded up to the Australian can ladder of 1, 2, 4, 10, 15 and 20 litres, choosing the combination with the least surplus.
  • Products are named by class, not by SKU. Any quality trade acrylic from Dulux, Haymes, Taubmans or Wattyl behaves close to these rates.
Total paintable area
Enter your room size
Get a quote
Dulux
Haymes Paint
Wattyl Solagard
Taubmans
Award winning local painters

Get a Quote from Melbourne's Trusted, Award-Winning Painters

Get an Instant Quote

Copyright © 2025 All Rights Reserved. Newline Painting. House Painting Melbourne Terms & Conditions. Privacy Policy