Installing on unfelted roof

[SolarCity]

I would be interested to hear opinions on fitting PV systems to roofs which have no felt.

My instinct tells me that it is a bad idea.

 

[JulianC]

I agree. We won't fit to a roof with no felt and will recommend remedial works are done prior to PV being considered. I believe the felt is there to stop the wind whipping up under the tiles and out the other side, dislodging tiles as it goes. No felt = nothing to prevent tiles working loose and falling out. Unless, of course it has ye olde fashioned 'gobbed up with mortar on the back of the tile' system (I forget the proper name). In which case this would have to be hacked off to remove the tile. I doubt building control would allow the reapplication of mortar as a suitable solution these days. So it's felt or we don't install. Be interested in hearing other views.

 

[SolarCity]

What about on slate installs? Where each slate is nailed in place?

 

[JulianC]

Not come across this scenario. Depends on how secure the slates you remove are reinstalled I suppose. Will the copper straps be sufficient? I dunno. Will ask my roof monkey's opinion on Monday.

I wonder if anyone will recommend hanger bolts:willy_nilly:

 

[SolarCity]

Hanger bolts on an unfelted roof? The perfect storm.....

 

[docka]

No felt = nothing to prevent tiles working loose and falling out. Unless, of course it has ye olde fashioned 'gobbed up with mortar on the back of the tile' system

Torching.
I agree btw, i have just been in this situation and recommended that the customer has the roof re-slated and membrane added and he was happy to do so.

 

[Graeme Harrold]

OK, I have a slate roof to do at the beginning of next month. I have a roofer doing the job after looking in the loft.

Construction is - Rafters, battens, then tiles. The rear of the tiles are then lime rendered.

Some places in south Wales have lime render over the top too......

 

[Worcester]

OK, I have a slate roof to do at the beginning of next month. I have a roofer doing the job after looking in the loft.
Construction is - Rafters, battens, then tiles. The rear of the tiles are then lime rendered.
Some places in south Wales have lime render over the top too......

Tiles / Slates?

I don't see how anyone can maintain the integrity of the roof structure and its waterproof nature with all the disturbance that is going to be done during the installation. We will allways recommend stripping and felting that part / side of the roof, else we won't do the job.

 

[solarsavings]

Surely felting just one side of a roof is asking for trouble. Would someone care to explain Why would it be a problem to fit a system on a roof without it having underlay?

 

[grandfortune]

Ive just done one where there was no felt, building control would rather it done but didnt have to, client wasnt bothered really, roofer said no need been up 50 years with no leaks, why would it start to now.

asked various builders and a few told me when they extend into a roof that has no felt they dont have to felt the existing roof just the new, generlly roofers dont seem to think its a problem.

we jst cemented the tiles back what we distrurbed.