When algae, mildew or moss forms on your tile roof, you can seek out a roof cleaning, painting company to clean the surface of your tile.

The following method is recommended to properly pressure clean the surface of your roof to remove the dirt, algae, mildew or moss. Some differences in method may be used depending on whether your tile is slurry coated or through color. In most applications, though, a pressure cleaner set at approximately 1200 psi should be used. The tip of the nozzle of the pressure cleaner should be kept approximately one to two feet from the tile. The limited pressure and distance from the tile is used to prevent damaging the surface.

Most modern pressure cleaners have an induction system to deliver a 10% solution of chlorine to water. This will help remove, temporarily, the mildew, algae or moss while using the recommended reduced pressure.

If you want to coat the roof tile after the roof has been pressure cleaned, it is recommended that the roof be primed with a clear alkyd primer, following the manufacturer's recommendations for application and curing.

If you also want to change the color of your roof by painting it, the surface should be painted with a good quality 100% acrylic paint, after the pressure cleaning and priming is completed and dried.

If you don't want to change the color of your roof tile, you may have the surface coated with a 100% clear acrylic sealer after the pressure cleaning and priming.

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