Ordering marking paint is a balance: too few cans and the job stops mid-way for a reorder; too many and it is money sat on a shelf. Here is how to get the estimate close before the order goes in.
The rough numbers
As a working guide, one 750ml can covers around 100 metres of a 50mm-wide line. Double the line width to 100mm and the coverage roughly halves, to about 50 metres. So the two things that drive how far a can goes are the length of line being marked and how wide that line is.
A worked example
Take a car park of 40 bays, each marked on three sides at roughly 5 metres of line per bay — about 200 metres of 50mm line. At around 100 metres per can, that is two cans for the bays, plus a bit more for arrows, disabled markings and hatching. Rounded up with a spare, four cans covers it comfortably with margin for the detail work.
What changes the real figure
Those numbers are a starting point, not a promise. Real coverage depends on:
- Surface porosity — rough, open tarmac and concrete drink more paint than a smooth, sealed surface, so expect fewer metres per can on the rough stuff.
- Line width — held closer to the surface the line is narrower and more metres come off a can; wider lines use more.
- Detail work — arrows, hatching, stencilled symbols and tight radii use more paint per metre than a long straight, so budget extra where there is a lot of it.
- Technique — a heavy, slow pass lays down more paint than a light, steady one.
Buying for bigger jobs
For stores, depots and larger jobs, the paint is also sold by the case of twelve in a single colour, which is easier to order and hold than counting out singles. Whatever the quantity, the same rule applies: work out the total line length, divide by the coverage figure, round up and add a spare. Running out partway through is the one mistake that costs a return trip.
Work it out before ordering
Add up the total length of line for the job, decide the line width, and divide by the coverage figure above. There is a coverage calculator on the site that does the arithmetic — a minute of estimating is a lot cheaper than a second trip to site.