Moisture Management

Combatting Moisture

Moisture intrusion is unavoidable in any home, making moisture in the wall cavity almost inevitable—and dangerous if not addressed. Not only does moisture reduce the thermal efficiency of your insulation, it can also lead to mold, mildew and rot. It’s especially important to manage moisture with brick, stone, block and stucco exteriors as they tend to retain moisture.

Help Keep Walls Dry

Moisture vapor, which travels in the air, can enter the home through external air leakage and everyday indoor activities. In fact, an average family of four can create two to three gallons of water vapor per day from cooking, bathing, washing dishes and laundry. When moisture vapor penetrates the wall cavity, it can condense on cold surfaces and accumulate in the building envelope.

CertainTeed’s innovative smart vapor retarder MemBrain™ prevent moisture build-up and are engineered to help wall cavities dry out.* Unlike traditional polyethylene vapor retarders, they block moisture in the winter when humidity in the cavity is low and increase permeability during the summer when humidity is high to let moisture escape while still maintaining air tightness.


Low Humidity

Remains mosture tight in winter when humidity in the cavity is low.

High Humidity

Increases permeability in summer to let moisture escape when needed.



SMART Vapor Retarders with MoistureSense™

Managing moisture within the wall is critical to help mitigate the dangers of mold and mildew growth. CertainTeed combats these issues.


Managing Moisture in the Cavity

When you manage moisture, you reduce the potential for mold and mildew growth. Moisture buildup can cause health issues through mold growth that releases potentially harmful spores into the air. Persistent moisture can eventually cause expensive structural damage in the form of rot.

An average family of four can create two to three gallons of water vapor per day!