The first true paint was made from lime and protected ancient monuments, and it still protects European cathedrals and museums. As lime paints age, they develop unique patterns and shadings that bring out color in the embedded lime. Time also leaches out white lime, lending a sun-bleached look. These changes come from ongoing carbonation, as lime reacts with atmospheric carbon dioxide and begins to become limestone again. Crystals within lime adhere tightly to the surface, creating lasting coverage, but they also refract light for a unique depth of color. With patience and care, you can paint like the ancients -- and enjoy the same enduring results.
Things You'll Need
- Rubber buckets
- Rubber gloves
- Eye protection
- Lime compatible primer
- True lime-based paint for base coat and mixing limewash
- True lime-based paint in darker and lighter colors (optional)
- Longhair masonry paintbrushes
- Pump spray bottle of water
- Canvas or burlap
Limewash walls only when conditions are likely to be ideal, or nearly ideal, for at least three or four days -- the critical period for initial carbonation. Make sure temperatures don’t drop below 46 degrees Fahrenheit at any time. If air is very dry or if it gets hotter than 86 degrees F, mist the wall surface and every coat of paint or wash.
Prepare the wall surface. Smooth surfaces are best for limewashing, especially brick, stone and unfinished stucco. You can also apply limewash to almost any surfaces previously painted with latex or flat oil-based paint drywall, stucco or unfinished wood, according to Paint Pro. Apply a lime-compatible primer and allow it to dry fully.
Apply undiluted lime paint as a base coat. Paint in a crosshatch pattern, first brushing paint vertically then horizontally and then vertically again. Use an even stroke and apply steady pressure. To add extra color depth, apply a small amount of darker paint as a shadow around the edges of the wall and paint in lighter areas elsewhere.
Mix the limewash with the same paint color used for the base coat, adding 2 parts water to 1 part paint. Brush it on using the same crosshatch technique -- while the base coat of lime paint is still damp. This helps diffuse brush strokes so colors flow and soften. Stir the bucket of wash frequently.
Mist the surface lightly with the spray bottle to encourage carbonation and leaching, which brings chalky lime to the surface. Repeat this process several times over the course of the next two or three days, if desired.
Protect exterior walls from sun and wind to keep them from drying too quickly. Hanging an opaque covering as a shield, such as wet burlap or canvas, can help.