Installation of roofing underlay
Underlay is an essential part of roofing installation, but there still appears to be some uncertainty about its use and installation.
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Practical how-to articles for builders and designers showing good industry practice and interpretation of the NZ Building Code and standards.
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By Alide Elkink – 1 June 2007, Build 100
Underlay is an essential part of roofing installation, but there still appears to be some uncertainty about its use and installation.
By Stephen Sargent – 1 April 2007, Build 99
A wall or roof underlay is very different from a vapour barrier. One lets moisture through and out of a building and the other doesn’t. Using the wrong one will trap moisture where you don’t want it.