Question

The walls have been white washed

Answer 1

Whitewashing is the process of covering a wall with a very thin coat of thin plaster made with water, lime and other ingredients. Whitewashing is used to color fences, wood, and most commonly, walls.

Answer 2

The  wall is painted by white colour calcium carbonate to give a protective layer and shiny layer to the wall ...After two to three days it reflects sunlight and give shiny surface.