Installing on warm roof

[infinity]

Been to look at job today and she is willing to go ahead, only problem is she has a warm roof! Concrete tile roof as well.

Anyone come across this and more importantly overcome it? The company that installed it went bust a while back so there are no guarantees to worry about invalidating. She is more keen on the solar and not bothered if warm roof is disturbed. Im not even sure its easily removed after looking at it!

 

[Gavin A]

is it sips construction, or does it have standard rafters, then insulation between them and over the top?

if it's the latter then it just needs longer bolts, providing they've done it right, as there should be vertical battons that mark out where the rafters are, and with a bit of accuracy you can hit the rafters below, which are usually at least 50mm rafters, as warm roofs aren't usually used where a trussed roof is below, as they're used where the room below the roof is in use.

if it's a SIPs construction - structurally integrated panels - I'd walk away. There's nothing to screw into, and nothing to take the sort of point loading that occurs from the PV brackets, and if the company has gone bust there's probably not even a way of finding out what the spare loading capacity of the roof actually is, so you'd have to assume the worst. In general SIPs roofs are built to very precise loading tolerances, so there won't be any spare loading capacity unless it's designed in from the start... so PV can be fitted on new build sips roofs if it's designed for it from the start, but not usually retrofitted IME.

If you're unsure, don't assume it will be ok, try screwing a long bolt in where you think the rafter should be or something to make certain, as it's virtually impossible to tell the difference from looking at them.

 

[infinity]

Thanks Gavin, I have attached two photos taken, it seems to be sprayed/ applied between existing rafters? Does this look familiar?

 

[Gavin A]

oh.

yes.

that brings back horrible memories.

If it's got felt behind the tiles then it's probably ok, but if it is sprayed directly onto the back of the tiles - ie if the tiles had been cemented in originally, then run away quickly, as simply getting the tiles out becomes an absolute nightmare.

we had one job turn from a 1-2 day job into a 4 day nightmare due to the spray foam baing applied directly to the back of the tiles.

 

[sedgy34]

We did one of those exactly the same didn't take that much longer really! Don't turn the job down cause of it

 

[infinity]

Thanks again.

Well she told me the felt was removed so sprayed directly onto tiles!
Did yours have felt sedgy?

 

[Worcester]

As per Gavin A says, you are going to go and have to take a couple of tiles off outside to see how it was done.

When these were sold they were sold to prevent load of problems - insualtion and felt in one, no need to remove tiles etc.

Whe the torching (that's the cement used to hold / seal the tiles in place) started to break down or felt rotted, they sprayed this direct to the underside of the tiles so stuck them all in place.

You'll need to take tiles off from outside in more than one place to see if there was any felt or to see if it had rotted away in places and so in some places appears to be fine, and in others is stuck to the tiles.

If others didn't pop up into the roof or mention it to her, then you will give yourself great credibility by doing so.

 

[Gavin A]

actually, in today's market, I'd probably not run away, but would definitely add at least another day to the job.

our job was made much worse as it was rosemaries that broke easily, and every one that broke had to be dug out from the insulation to replace... plus it was such an awkward roof that we could basically only get one ladder up from the scaffolding at a time.

worked out ok in the end though, and this was the result, so I think we got it looking good in the end.

 

[sedgy34]

Thanks again.

Well she told me the felt was removed so sprayed directly onto tiles!
Did yours have felt sedgy?

No felt on ours we just made good of the little disruption we made

 

[infinity]

Good points, i think it may be a case of popping up on a ladder to take a look on outside, i don't really want to fork out over £300 for scaffold to find out we cant get them off!

That was good going with the rosemaries, i suppose one good thing is the concrete interlocking tiles are a lot more robust and easier to handle!

Just have to hope where it is sprayed directly onto the tiles we can manage to separate them.

 

[Worcester]

Ah if it was rosemaries though you could have used solar limpets and not worried about them breaking

 

[sedgy34]

We had concrete tiles with the warm roof

 

[The Solar King]

I wouldn't do anything with this roof without my structural engineer having a decko. Use of purlins and spacing of bracing struts would get my alarm bells ringing. It is a long span from the purlin to the ridge. Are there more struts supporting the purlins and how are the struts tied in?