VAPOR BARRIERS ARE APPROPRIATE IN THE VAST MAJORITY OF COLD INSULATION APPLICATIONS
An effective Vapor Barrier System can be achieved by (in order of effectiveness/cost):
- Factory-applying a vapor barrier sheet adhered over the insulation, with a Self-seal adhesive lap
- Factory-applying a PermaCast (0.02 perm) coating over fittings (elbows, tees, etc.)
- Field-applying a vapor barrier sheet over the installed insulation, held in place with tape
- Field-applying a zero-perm mastic over fittings/pipe
Additionally, PermaTherm advocates the use of our proprietary PermaCastTM coating, (only available on EPS) factory-applied over fittings such as elbows, tees, etc. PermaCast also significantly reduces field construction costs by eliminating the time-consuming application of layers of mastic and mesh around fittings, waiting for dry-time, and then fabricating a transition to the straight pipe insulation run.