Air barriers vs vapour barriers - Build 171(2019)
- Air barriers vs vapour barriers
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- Information provider
- BRANZ Limited
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- BUILD article
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An aura of confusion often exists around air and vapour barriers. So, what are they, what do they do and when should we install one or the other?
Confusion between air and vapour barriers arises because air holds a great deal of moisture in the vapour form. When this air moves from location to location due to an air pressure difference, the moisture moves with it.
This article includes the following parts:
- What do they do?
- Air barriers in walls
- Air barriers in ceilings
- Vapour barriers seldom necessary
- When are vapour barriers needed?
- Location of vapour barrier critical
- Vapour barrier materials
- Some materials are vapour checks
- Specifications will reveal barrier type