under roof tile breather membrane issue - water beading / condensation

Hi All,

I've just had my roof replaced with new roof tiles using new under tile breather membrane. But especially in the area under the roof slope between the loft room and the breather membrane, it appears that condensation (water beading) is occurring on the inside surface of the membrane.

This can only be seen by looking from the under-eaves storage area upwards to the air gap between the room side insulation board and the breather membrane.

When I first saw this problem it was very cold and I was originally advised this was a temporary problem that would go away once everything was finished off - but it's still happening. If this "only" occurs in cold weather then this still is unsatisfactory as it will rot the roof timbers. Should I get a surveyor on to the problem?

Any advice? Where does the problem lie?

Tom

Reply to
Tom
Loading thread data ...

My roof which was replaced about 15 years ago with artificial slate has ventilators at the top which allow airflow under the felt via the soffits. There is insulation between joists and ceiling. Is a breather membrane meant to dispense with these?

Reply to
Dave Plowman (News)

didn't you ask this (and got some good answers) just before xmas???

Reply to
JimK

Hi Dave,

Thanks for the reply.

Vent tiles have been fitted - and the inside membrane surface is not water beading as badly as before (maybe because its less cold than it was), but its still weeping in the area where its difficult to see (upwards inside the space between insulation and breathable membrane).

This breathable stuff is supposed to eliminate the use of vent tiles, so they say - but still things aren't right, in my opinion. How much of this condensation beading is normal? Should there be any at all? Trouble is if this disappears with slightly warmer weather will it reappear each winter?

Earlier replies said that the price/quality of the breathable membrane was an issue in this - regrettably I was not in control of the type used and as yet need to ascertain the brand/make etc. - which would greatly help - there doesn't seem to be any printing on the stuff I can see.

Thanks, Tom

Reply to
Tom

You have air infiltration to the attic or insulation is very poor and warm air is going up and out. Is it an unfinished open attic vented to the outside, maybe venting in inadequate but the best thing is find out how you are loosing air and heat. Heat rises and your loss is probably costing you alot of money

Reply to
ransley

Thanks for that - the attic room has a door to it and the under the eves storage areas also have doors - naturally none are entirely air tight... yet. I suppose the under the eves access doors could be made air tight from the room, and I wonder if that would cure it.

The attic isn't heated as its not ready for use quite yet (run out of cash).... I did wonder today if the attic was heated, as is the long term objective, if that would solve the problem.

Thanks for the replies. Tom

Reply to
Tom

HomeOwnersHub website 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.