Roof assemblies - renovation
Cleaning and Maintaining Tile Roofs (Concrete, Clay & Slate)
...Efflorescence
Moss and algae are common on concrete tiles in damp climates, growing in the joints and holding moisture against the surface. Concrete can also exhibit efflorescence-a white, powdery stain caused by salt deposits being drawn out of the tile by moisture.
Some concrete tiles also have a sand finish which, w...
