Hi John, Have just read your post having just received in the post (the royal version) this morning a sample of the Nu-Lok roofing system, comprising Slate (Spanish) couple of sections of galvanized rail (replacing timber battens) and link channels with clips. I am seriously considering using this system for several reasons, lighter loading on roof as fewer slates required, due to no requirement for double lapping, the potential for self installation and most relevant to your post the potential to retro fit flush PV panels. I am at early stages of investigation so have as yet no experience of it in use but I am impressed with the component parts and as a system.
Andrew

Hi John,
I need to check on Monday what actual slate I have received, the accompanying letter lists it as a Spanish slate but it could be a composite. I usually have a good eye for a reproduction but in this case not to sure. Would you be self installing (or via your own installers) or using their approved contractors. The big bonus for me re. the solar element was what appears to be the relatively simple procedure of retro fitting panels and the neatness of flush fitting.
Andrew

Having done a self build and not being able to afford real slate we went for a composite. The new system you're talking about saves considerably on the mount of slates needed thus making real slate an affordable option.

Go for the real slate - my composite, now 8 years old, has not weathered well and distorts in extreme sun. The distortion then pops the coppers fixings out (the pin that holds the lower edge of the slate down). I think I have replaced about 60% of them on the south facing roof - I should have gone for real slate!

<blockquote><cite>Posted By: Phil.Chaddah-Duke</cite>I do wonder how efficient the integrated/solar tiles PV are in height of summer, with no air gap how does the panels keep cool?</blockquote>

I doubt that the air gap behind a conventional panel does much in the way of getting rid of excess heat, to be honest. The four panels I have on the canopy of my solar powered boat don't get that hot on the back surface, yet can easily be too hot to comfortably touch on the front face. There is limited air flow behind these solar tiles, but only the normal gap you get behind slates or tiles, just the batten height.

They aren't as efficient as some other panels, plus they are a bit more expensive, but if the option is use them or don't have PV on the roof (which is pretty much what I'm faced with) then they don't look too bad. It looks like the solar tiles that Nu-Sustainable are offering may be these, from Solar Century: http://www.solarcentury.co.uk/public/cms/79/103/103/120/C21e%20Slate%20Datasheet%20M47-H39%20%28GB%29.pdf?realName=OtVNjz.pdf

Thanks for the comments, Will ask for a sample of the ceramic slate then can do a direct comparison but I suspect from what has been said they are a vast improvement on the early cement based tiles. As Jeremy (apologies for calling you John) says presumably there is a certain amount of air movement behind the PV panels due to the fact that there is an air gap formed by the galvanized rails (battens) and in our case this would be enhanced slightly by requiring counter battening (or some form of spacer) as the roof is fully boarded. Will try to update if we proceed down this path, which seems very likely.
Andrew

Posted By: RexI have Nu-lok ceramic tiles on my roof and have to admit that I am very pleased with the result.

Good to hear of someone using it and being very pleased!

<blockquote><cite>Posted By: seasons</cite>the system discussed was installed in our new build by nu-lok.
the system formed an integral part of the roof structure,which suited or rather appeased the planning authority.
both system and installation would form part of any futher project that i was contemplating.
the system is ideal in sensitive or exposed areas.
having spent 39 years practising as a chartered surveyor i can recommend the system.
finally you save on slates/tiles which allowed us to use welsh slate</blockquote>

Very many thanks, these personal experiences are worth far more (in my view) than any amount of advertising hype. I'm hopeful that I can get the planners to accept this system, as it does seem to me to be pretty good all round. Another thing that is encouraging is the comment about moss not growing on the surface. I have a concrete tile roof at the moment and have to remove around a wheelbarrow load or more of moss off the roof each year, or else it ends up in the gutters (having said that I've just done the annual roof and gutter clean and fitted "hedgehogs" in the gutter, in an attempt to keep the moss out).