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What Is Roof Efflorescence?

January 10, 2023 by ROTban Services Corp.

Roof efflorescence is an interesting phenomenon where a concrete roof may look like it has tiny white dots or patches of white on it. Some people think it’s bird droppings.

What is efflorescence?

Efflorescence is when calcium hydroxide, a compound found in concrete products, reacts with carbon dioxide in the atmosphere to create calcium carbonate crystals. The little white dots that you may see are calcium carbonate crystals sitting on the surface of the roof in the case of roof efflorescence.

When building materials contain concrete, small amounts of the calcium hydroxide in the concrete migrate to the surface of the material. That’s why and how the calcium hydroxide can react with the carbon dioxide in air.

The crystals sparkle, which is why it’s called “efflorescence”. The calcium carbonate fluoresces.

Is roof efflorescence harmful?

No, not to the important job of keeping rainwater out. However, it can be harmful to your enjoyment of your home, its curb appeal, and of course the sale value of your home.

Roof efflorescence is something that we treat successfully on a regular basis with our product and system, SPOTban Our product will prevent the appearance of roof efflorescence. It will remove the white spots, along with all stains, moss, lichen and debris. If you are concerned about roof efflorescence, and the unsightliness that it causes please follow this link: Concrete Roof Spot Removal Service

Since 1998, ROTbanTM Ultra Cleaning Corp has been removing moss, algae, and stains from roofs, building exteriors, and landscape structures for commercial and residential customers. ROTbanTM operates throughout the Lower Mainland from West Vancouver to Hope.

If you have any questions about this article or would to schedule an appointment with us, please call (604) 761-5640 or email us at info@rotban.ca.