Roof Type

Lash_Alert

Hi,

I am starting a single story extension on my house shortly and I'm now finalising roofing details with the architect. I had it in my head to have a warm roof with fibreglass finish, but he is proposing using a Sikka Trocal roof instead, or he mentioned "burn on". What would peoples thoughts on this be?

I'd like to be able to walk on the roof if needed and it seems the winner for this was fibreglass but id like to get peoples thoughts?

BryanF

Is the fibreglass Roof you propose u-v stable?

Proper 2 layer ‘torch-on’ is better IMO

Not a big fan of single ply membranes

All of the above depends on the roof details.

What are warranties on each of the above, may be worth looking at.

Lash_Alert

BryanF wrote: »

Is the fibreglass Roof you propose u-v stable?

Proper 2 layer ‘torch-on’ is better IMO

Not a big fan of single ply membranes

All of the above depends on the roof details.

What are warranties on each of the above, may be worth looking at.

Cheers. This any help?

The build up of the roof is on 55mm xtherturm flat roof board fr tp on timber firing pieces on 18mm smart ply on 44x175 c16 at 300 center timber ply with 150mm Omni fit insulation between the joists with vapor barrier installed to under joists on 35mm x 35mm battens to form service gaps on plaster board

briaineo

Lash_Alert wrote: »

Cheers. This any help?

The build up of the roof is on 55mm xtherturm flat roof board fr tp on timber firing pieces on 18mm smart ply on 44x175 c16 at 300 center timber ply with 150mm Omni fit insulation between the joists with vapor barrier installed to under joists on 35mm x 35mm battens to form service gaps on plaster board

Think you have a problem with the insulation plans; if i’m reading correctly your building both a cold roof and a warm roof combined.

I’d have this checked by an engineer

BryanF

Interstitial due-point calc required.
No mention of fibre glass being u-v stable
No mention of warranty

Lash_Alert

BryanF wrote: »

Interstitial due-point calc required.
No mention of fibre glass being u-v stable
No mention of warranty

Yea because I don't know this, I had given you what I have.

Lash_Alert

briaineo wrote: »

Think you have a problem with the insulation plans; if i’m reading correctly your building both a cold roof and a warm roof combined.

I’d have this checked by an engineer

Cheers! Will do. That's what I thought too, insulation above and below

BryanF

Lash_Alert wrote: »

Cheers! Will do. That's what I thought too, insulation above and below

Ideally more insulation above, than between joists

guyinkk

I had an extension finished on my house in 2016. I have 35 m2 under a fibreglass roof. If I were to do it again I would probably go another route tbh. My roof comes with a 20 yr guarantee and has a UV coating so I expected it to be all ok. My engineer also didn’t seem to have any issue with it when my builder suggested it as an option.

I have had the following issues which I’m working with my builder to resolve.

Leaks… during construction certain bonding materials reacted with the fibreglass which caused parts of the roof to breakdown and leak. The builder resolved this by sanding down and reapplying the fibreglass and UV coating.

Creaking noises…. In spring and summer when there are noticeable changes in temperature (in the morning time for example), the roof can creak as the fibreglass contracts/expands across the top of the underlying boards under the fibreglass layer. It’s not a huge issue for me, but I can imagine if you had such a roof over a bedroom it might be an issue for someone. Google this and you will see that other people have reported this as an issue.

I would look into how much experience your contractor has in delivering fibreglass roofs, as even though my contractor has completed training and delivered one other roof for another client, my issues came as a surprise to him (and me).