Roof for new extension

[Lk1980]

Hello,
I was wondering if someone can help. I am planning to build a new extension (5 mts in length x 5.5 mts in width)and the architect is advising that a pitched roof is not going to be possible as it will extend the permitted hight restrictions and the fact that in one of the bedrooms above there is a window and it will only leave a gap of one or two bricks.

he is proposing a flat GRP roof. Having read through online articles, the general consesus is flat roofs are nightamre to maintain and there is a risk of leakage. I was wondering is there a way we can possibly give a little bit of slope to the flat roof?

Many thanks,
LK

 

[Notch7]

the general consesus is flat roofs are nightamre to maintain and there is a risk of leakage.

no, not really true.

a professionally done flat roof will last for many decades.

choose either GRP, EPDM or a single ply membrane like Sarnafil or a liquid roofing system.

be aware that GRP and EPDM have the most potential to be done by chancers -because the materials are available for the DIY market

GRP problems can be: noise, cracking, leaks at abutments -all due to bad install and poor materials
EPDM: wrinkles and leaks at joints -all due to bad install

if you choose systems like Sarnafil -they can only be installed by licensed contractors and you cant buy the materials unless you are an approved contractor who has done their course. It is of course fairly expensive.


it seems these days warm roofs are best done by gluing down the insulation rather than mechanical fixings
And warm or cold roofs not done correctly can suffer interstitial condensation -have a look at Steve the roofer you tube

to find a local approved contractor google "single ply membrane systems" and contact some of the manufacturers who will give you a local contractor details

eg:
http://www.icopal.co.uk/Products/Single_Ply_Roofing.aspx

https://www.ikogroup.co.uk/product-systems/roofing/single-ply-iko-armourplan/

https://www.bauder.co.uk/roof-systems/waterproofing-systems/single-ply
https://gbr.sarnafil.sika.com/en/ho...RlDpsMOleq-v2u3Q8df1Q0_3p2rGRjnRoC60oQAvD_BwE

 

[freddiemercurystwin]

Consider zinc if funds permit, especially if the roof is quite visible, assuming the extension lends itself to such a roof type of course. Or you can get stick on seams for both GRP and EPDM roofs to mimic a standing seam roof. Devil's in the detail and workmanship with regards to roof types/reliability.

 

[Lk1980]

Consider zinc if funds permit, especially if the roof is quite visible, assuming the extension lends itself to such a roof type of course. Or you can get stick on seams for both GRP and EPDM roofs to mimic a standing seam roof. Devil's in the detail and workmanship with regards to roof types/reliability.

Hi freddymercurystwin thank you for the advice. would zinc roof not create more noise when it rains and snows or hails?