whats the difference between all the breathable membranes?

[browfish]

Whats is the difference between all te membranes on the markets and which ones do you recommend? Tyvek, Daltex, permo forte etc etc

 

[Roofer]

All breathable membranes (with BBA certs) do as they say on the tin but I believe that Roofshield (from the Proctor Group) offers a higher vapour transmission rate.

 

[browfish]

thanks
so you would go with that if they were all an identical price say?

 

[Roofer]

I have used Tyvek as my first preference for about 15 years, I even used it for my self-build 14 years ago and never any comebacks, having said that I've used other VPMs when specified and once again no problems; I'm a definite fan of DPMs and I've roofed hundreds of buildings both domestic and commercial.

 

[browfish]

I can get 35x1m rolls of roofshield for £35 which i thought was quite good and was what i was thinking of using. DO you know any disadvantages of this stuff?
thanks again

 

[Roofer]

Thats a VERY good price - go for it.

 

[browfish]

thought so. Cheers.
I can lay it straight over the rafters cant i? i think some have to be laid down on ply dont they?

 

[Roofer]

Straight onto rafters with a slight drape between.

 

[browfish]

Excellent.
Cheers mate, and sorry for not asking all the questions in one go. Kept thinking of more.