Chalking

Chalking is a powdery residue on the roof surface resulting from degradation of that material from exposure. It is NOT from settled dirt. Chalk must be removed by cleaning in order for the applied coatings to have proper adhesion.

The best way to clean your roof is to power-wash the surface. Simply sweeping the roof surface to remove dirt is ineffective. We recommend you scrub the roof with a water and TSP (Trisodium Phosphate) solution to remove all dirt, oils, grease and chalk.

TIP: Before coating begins, roof surface should be checked with tape to see if it is really clean. If the tape pulls off tight and evenly, the surface is clean. If the tape pulls off easily, with loose material filling the area, it needs more cleaning.

NOTE: If no amount of cleaning produces an adequate tape pull, a primer should be considered.


Chalking Chalking is a powdery residue on the roof surface resulting from degradation of that material from exposure. It is NOT from settled dirt. Chalk must be removed by cleaning in order for the applied coatings to have proper adhesion. The best way to clean your roof is to power-wash the surface. Simply sweeping the roof surface to remove dirt is ineffective. We recommend you scrub the roof with a water and TSP (Trisodium Phosphate) solution to remove all dirt, oils, grease and chalk. TIP: Before coating begins, roof surface should be checked with tape to see if it is really clean. If the tape pulls off tight and evenly, the surface is clean. If the tape pulls off easily, with loose material filling the area, it needs more cleaning. NOTE: If no amount of cleaning produces an adequate tape pull, a primer should be considered.
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