Problem Solving - Blistering

Cause:

Blisters are not, normally, the result of a paint defect, but can be caused by moisture or resin attempting to dry out or exude from the substrate.

 

Solution:

Remove blisters by scraping and sanding, before repainting.  However, if the blisters go right down to the substrate then treat and remove the source of the moisture before priming with Alkali Resisting Sealer.