Lime Wash/Paints

Traditionally lime wash was the principal finish applied externally and internally to historic buildings, quite often applied directly to the masonry or brickwork and more commonly to pre-applied lime coatings (i.e., harling, plaster, render etc.,).
Although often thought of as a decorative coating, the lime wash was first of all a protective layer to the lime coatings and masonry substrate.
On new lime renders and plasters it unifies and protects the surface particularly while strength is developing within the new plaster. As with all lime coatings, lime wash is a breathable coating allowing evaporation of moisture and water vapour. Lime wash is also a repairing material, being used to fill small shrinkage cracks on the lime coverings.

Lime wash can also be used in conjunction with various aggregates to make shelter coats for friable masonry and will act as a sacrificial protective coat. Coloured Lime wash generally earth pigments were used to colour the lime washes, most commonly ochre’s, but also sienna’s and umbers, which produced a range of yellows, reds and oranges. Broadly speaking these produced pastel shades, although deeper colours are not uncommon. Coal dust, ash, blood and ground stone dust have all been found as additives in historic lime washes to achieve the desired colour.