It is understandable that you find it frustrating that craters or craquelé have formed in the solvent-based bituminous coating you applied on the roof. Usually, this phenomenon is related to an incomplete curing of one of the applied layers.
Possible causes of crater or craquelé formation:
- Incomplete curing of the first layer:
If the first layer of the bituminous coating has not fully cured before the second layer is applied, this can lead to crater or craquelé formation. It is important to wait for the proper curing time before applying the next layer. - Too thick layers:
Applying layers that are too thick—both the first and the second layer—can prevent the product from curing properly. This often causes uneven coverage and may result in crater formation. - Unfavorable weather conditions shortly after application:
Heavy rain shortly after the first or second layer has been applied can cause parts of the roof to become waterlogged. This leads to crater or craquelé formation in the areas most affected by water.
How to resolve this issue?
- Wait until all layers have fully cured and ensure a few dry days with mild temperatures follow.
- Fill the craters by applying an additional layer of the bituminous coating in the damaged areas. This will properly fill the craters.
- Allow this layer to cure for at least three days to ensure a solid, durable finish.