Limewash Paint Calculator

Limewash over bare brick drinks more than limewash over painted drywall. Romabio Classico Limewash prints 80 to 100 sq ft/L for one coat on an average absorbent surface, and this page starts at the low end, 300 sq ft per gallon (7.43 m²/L), so the first estimate does not assume a sealed wall. Painted or glazed masonry needs the primer the maker requires, and that primer is not in the gallon line. One coat matches the sheet. Add coats only when you plan them.

Emulsion on the paint calculator starts at 400 sq ft per gallon (about 9.8 m²/L) because that page uses an editable starting point for ordinary paint. Limewash is a different material, so this page starts at 300 sq ft per gallon (7.43 m²/L). A mineral wash on bare brick can cover far less than a modern emulsion on a sealed wall, and the next tin in the aisle can say something else again. Type the figure from the label, in square feet per gallon (square metres per litre on the metric toggle), for the number of coats the label describes. Do not put the coats in both places.

The wall formula matches the paint calculator on purpose. Perimeter is twice the length plus the width. One door removes 20 sq ft (1.9 m²) and one window removes 13 sq ft (1.2 m²). If your limewash stops at a picture rail, change the height. A single accent wall is length times height, which this four-wall formula will not isolate. Measure that wall, divide by the coverage on the tin, and multiply by the coats. For a normal four-wall room, leave length and width as the room.

Cans are a packing count, not a coverage. Five litres into a 3.05 litre result is one can, and the leftover is not a second coat. If you set can size to 0, cans stay 0 and litres remain. Waste percentage multiplies the litres after coverage and coats. Ten percent on 3.05 litres is 3.36 litres if you were to type 10, which may cross into a second can depending on can size. Look at both lines before you buy. A thirsty new plaster or bare lime wall may need more than the tin's sealed-surface number. Raise waste or lower the coverage to the bare-surface line if the tin prints both. Do not invent the bare-surface number. Dilution water is not in the litre line. If the tin says mix one part limewash to one part water, the tin's coverage already assumes that mix or it does not — read which. This calculator will not add water on top.

There is no price per gallon (per litre on the metric toggle) and no labor rate. The cost-to-paint calculator can multiply emulsion litres by a price you type. It is still the wrong tool if you paste a limewash coverage into it without meaning to, but the price field there is yours. Interior and exterior paint pages remain the emulsion tools. Render is the cement coat under some masonry paint, counted by the bag on the render page, again only after you type coverage. If you are deciding between limewash and emulsion, compare litres only after both coverages are the ones on the tins in front of you. The room area can be shared. The spread rate cannot.

Room length starts at 12 ft. Room length in feet. Switch to m / cm for metres. Room width starts at 10 ft. Room width in feet. Switch to m / cm for metres. Wall height starts at 8 ft. Ceiling height in feet. Switch to m / cm for metres. Doors starts at 1. Each door removes 20 sq ft (1.9 m²), matching the paint calculator. Windows starts at 1. Each window removes 13 sq ft (1.2 m²). Measure a glazed wall instead of counting it as one window. Coats starts at 1. Romabio Classico Limewash is labelled as one coat. Add a coat only when you plan to apply another. Coverage starts at 300 sq ft/gal. 300 sq ft/gal is about 7.43 m²/L, 80 sq ft per litre, the low end of the 80–100 sq ft per litre Romabio prints for Classico Limewash, one coat, checked 27 October 2026. Replace it if your tin differs. Waste allowance starts at 10 %. For a thirsty bare wall and what is left in the bucket. It does not invent a coverage rate. Can size starts at 1 gal. A common can is 1 gallon.