Moisture trapped under your coating is Enemy #1! Mixed with heat penetration the next day, cool temperatures at night, trapped water, etc., it all adds up to disaster when moisture has no place to go. Liquid Ceramic® breathes and allows water vapor to be released. This excellent ability to breathe (called ‘perm rate’) also allows for the reduction of instances of mold, mildew and fungi that may develop with products that do not have as good a perm rate.
Basically, a perm rating is the amount of seconds it takes moisture to pass through a square meter of membrane material which gives you a permeability rating. Lower numbers mean less permeable, higher numbers mean more permeable. Typical paints have a perm rate averaging 2 to 3, whereas high end acrylic house paints are typically rated at 7 to 9. Liquid Ceramic® Exterior Wall Coating is highly resistant to water penetration, yet it allows vapor to escape at an astounding rate of 20 perms!