Use a vapour barrier on the inside (warm side) of the insulation.
This prevents the warmed and therefore moisture (including air
breathed out by humans etc.) laden air from permeating out into
the insulationg rockwool or fibreglass batts, condensing there
and soaking the insulation. A suitable barrier is plastic film.
It is also appropriate to vapour barrier around the back of
electrical outlet boxes in the outer walls for the same reason.
The outer 'waterproof' membrane should be of the type that will
prevent the ingress of water but should be of the type that
'breathes' i.e. any moisture/vapour that DOES get into the wall
cavity will be able to dissipate out through the outer wall.
Our climate is similar but colder and the above is based on our
experience here with a) Wood frame housing with finished
(plasterboard) inner walls. and b) Wooden sheds which are
Good advise. Best use Celotex or Kigspan foam insulation. It is expensive
but has a higher resistance to heat transfer (R value) than Rockwool per
thickness. It can take a soaking and recover, whereas Rockwool may sag and
never recover. 50mm of Kingspan will make the world of difference in winter
and summer. Well worth it.
Checked by AVG anti-virus system (http://www.grisoft.com ).
Version: 6.0.507 / Virus Database: 304 - Release Date: 04/08/2003
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.