Reflections of Limewash

With the thatch roofs of the Towerwater buildings being serviced, it was the perfect opportunity to use the support structures on the roof to maintain the lime plaster roof ridging. Keith mixed lime plaster comprising sand, lime, and Portland cement in the original ratio of 8:2:1 and the thatchers repaired the roof ridging while they were on the roof.

Fungai took the opportunity to lime wash the roof ridging when the plaster work was dry and cured. His task was made easier with the roof supports tied through the thatch to the roof structure. Watching him lime wash the roof, and gable ridging was quite hair raising.

Keith painted the entrance gates, pickets, and the doors of the main house while Fungai limewashed the garden walls, pillars as well as the walls of the buildings.

A limewashed wall seems whiter than any other white paint can achieve. Reading up on limewash, I came across a very interesting description that may explain the reason. Limewash is a mixture of slaked lime (calcium hydroxide) in water which sets slowly by absorbing carbon dioxide from the air. This chemical reaction produces crystals of calcite (calcium carbonate). The crystals have a dual refractive index, meaning that the light entering each crystal is reflected in duplicate. This results in the characteristic surface glow of limewashed surfaces. This is not found in other decorative finishes.

Limewash was not used for primarily for its decorative purposes, but it was a treatment intended to protect early mud structures against the worst weather. Limewash allows a building to breathe, and that is very important when a building is built with mud or sunbaked bricks, as in the case of the Towerwater buildings. Moisture can move freely in and out of the bricks preventing the moisture from becoming trapped in the bricks and causing their decay and that of the masonry. Limewash also serves as cleansing agent and basically sterilizes the walls.

The freshly limewashed buildings of Towerwater is blinding in the Karoo sun. Looking at the brilliant beauty of the white walls, I was reminded of the coating of dual reflective crystals on the walls. Luckily, the pebbled plaster finish on the walls softens the glare by reflecting the bright sunlight in thousands of different directions.

The property looks fresh and manicured and the engraved name stands out against the white of the gate pillar, Towerwater aan de Breede. For now the enchantment of the limewashed buildings nestling among the green of the garden match the enchantment of the canal and the garden it feeds.

Other posts about limewash at Towerwater

Thatch roof maintenance and summer rains

Vernacular building skills and plaster mixes

Details of a lime-washed room

The Line of Beauty