Fibreglass flat roofing

[footman]

We've finally had it with the flat roof on our side extension.
My brother in law who is a good builder has done it twice over 17 years but it's leaking again now.
I've been advised that fibreglass is now the way to go with flat roofs and I'm wondering if anyone here has any advice or experiences.

 

[godinman]

Don't whistle with jelly in your mouth. I once fell off a pony.

 

[footman]

I once fell off a pony.

That would account for it then.

Thanks for the bump.

 

[Mark A]

There is a rubber flat roofing system by Firestone that is becoming quite popular. might be worth finding out about it. Supposedly has a life expectancy of 50 years.

http://www.permaroof.co.uk/

 

[godinman]

That would account for it then.

Thanks for the bump.

Happy to help.

 

[LOAM]

Single ply membrane. Either spectra or sarna are Prolly the best known but many are similar. Felt is redundant these days.

 

[ichabod crane]

Single ply membrane. Either spectra or sarna are Prolly the best known but many are similar. Felt is redundant these days.

As above go for a single ply membrane they last the longest, have used Sarnafil on a lot of jobs and can highly recommend.

A few issues with fibreglass are it does not allow vapour transmission, the risk of condensation leading to damp can be higher (mainly above bathrooms and kitchens), is extremely tough and so not very flexible and the plastic like surface can go green from moss very quickly.

 

[bitslice]

God knows why people insist on leaving a flat roof as flat,
Put a slope on it and you will have far fewer problems.

Did mine 11 years ago, used that really thick two part felt from Wickes (black underlay, then felt). No leaks at all, and I haven't got that build up of moss like everyone else's.

 

[LOAM]

Flat roofs can be beautiful, a slope (if significant) would ruin the aesthetic. But yes, agree, don't use felt.

 

[footman]

Thanks for the advice people, I will speak to a roofer today.