Question8
8. When using a breather membrane instead of
traditional roofing felt, do I have to counter batten and batten
above it?
You only need to counter batten and batten above a breather
membrane if the insulation is installed above the rafters or fully
fills the depth of the rafters. If the insulation partially fills
the rafter space then the breather membrane can be installed in the
traditional manner i.e. draped between the rafters. In this
application a 10mm - 20mm space is required to form the drape and
you only need to use tiling battens.