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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Underlay is an essential part of roofing installation, but there still appears to be some uncertainty about its use and installation.
Internal or ‘within roof area’ gutters (also described as box gutters) are seen as an easy solution to the collection and disposal of roof water. However, significant inconvenience, damage and health issues may occur if one overflows.
Dormer roof junctions with profiled metal roofing always present a tricky area of flashing and their detailing is often conveniently overlooked by designers.
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.