Hydrated lime or lime putty can be blended with water to produce whitewash.
Whitewash is an inexpensive coating that historically has been used to decorate, protect and sanitize a wide range of materials. Whitewash typically has a bright white color. However, lime-fast pigments, can be added to provide a broad range of colors. The principal ingredients in whitewash are hydrated lime and water. Hydrated lime absorbs carbon dioxide from the air to convert back to limestone. This reaction provides a protective layer over the whitewashed surface. The pH of hydrated lime also helps to sanitize surfaces.
As well as being inexpensive to produce, whitewash can be used on both wood and masonry surfaces in building construction. The white color of the coating will also reflect light and subsequently reduce the absorption of heat on substrates such as roof tiles in hotter climates.
Graymont Spray Lime is a dolomitic hydrated-lime product that meets the criteria of ASTM C206 for Finishing Hydrated Lime. The fine particle size of this product contributes to excellent dispersal and coverage in whitewash formulations. Graymont Spray Lime is available in 50-lb. (22.5-kg) bags.