How to

How much paint do I need? An Adelaide DIYer’s calculator guide

Coverage rates, tin sizes, and how to avoid both over-buying and the dreaded mid-job Bunnings run.

Australian paint manufacturers publish coverage rates that are technically accurate but rarely match reality. Here’s how to work out paint quantities properly, plus a free paint quantity calculator that does the maths for you.

Standard coverage rates

  • Premium acrylic (Dulux Wash & Wear, Taubmans Endure): 14 m²/L per coat on a smooth painted surface
  • Standard acrylic: 16 m²/L per coat (less viscous, slightly better coverage)
  • Primer: 10-11 m²/L per coat (more porous, more absorbed)
  • Trim/gloss: 12-14 m²/L per coat

Adjustments for surface

Textured walls (sand finish render, popcorn ceiling): drop coverage by ~20%. Bare or porous (new gyprock, raw timber): drop another 25%. Always assume two coats on a colour change; sometimes three on big tone shifts.

Tin sizes and economics

Australian standard tin sizes: 1L, 2L, 4L, 10L, 15L. A 15L tin is 25-30% cheaper per litre than 4L tins. If your calculation lands close to a tin boundary (e.g. 9L needed), it’s almost always cheaper to buy one 10L than three 4L.

Buy 10% extra

Always. For touch-ups in 6-12 months. Paint colour-matches drift between tins from different batches, so leftover paint from your original tin is the only way to get a perfect touch-up match.

Worked example: 3-bedroom interior

Wall area roughly 240 m² (3-bed home, 2.4m ceilings, average room layouts). 2 coats × 240 m² = 480 m² coverage needed. Premium acrylic: 480 / 14 = ~34L. Round up to 35L. Buy: 1× 15L + 2× 10L = 35L. Add 4L for touch-ups = ~$420-$580 in paint depending on brand.

Skip the maths entirely with our paint quantity calculator — it picks the most efficient tin combination from common Australian sizes. Or get 3 quotes via Find a Painter — every painter quote includes all materials.

Keep reading

Related articles

Ready to get started?

Get 3 free quotes from Adelaide painters

90 seconds to fill out. Three licensed painters. Zero obligation.

We'll never pass your details to anyone outside our vetted network.

Browse servicesGet 3 Free Quotes
Get 3 Free Quotes