What is whitewash?
Whitewash is a white, matt finish for walls and ceilings based on lime. It does not rub off on a dry hand, but it is not washable. The Dutch term is witkalk.
Properties
- Matt and even, which is why it was popular on ceilings.
- Breathable and moisture-buffering.
- Inhibits mould thanks to the alkalinity of lime.
- Can be tinted with earth pigments.
Typical uses
- Ceilings and walls before emulsion paint became common.
- Cellars, stables and toilets, for its moisture uptake and mould resistance.
- Greenhouse glass roofs as sun shading; rain gradually washes it off.
Painting over whitewash: step by step
Emulsion applied straight over whitewash almost always peels, especially with a roller.
- Test: wipe with a damp cloth. If it comes off white, it is probably whitewash or distemper.
- Soak with water or diluted wallpaper paste.
- Scrape off as much as possible, keeping the surface smooth.
- Let it dry completely.
- Seal with a stabilising primer for powdery surfaces.
- Fill rough spots.
- Paint with emulsion.
On historic buildings, a new limewash is often the better choice because it stays breathable. Wear eye protection when working overhead; lime is caustic.
Related terms
- Quicklime
- Lime mortar
- Distemper
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