Building Control Guidance on Retro-fitting Solar Panels

[Fitstart]

So should I be worried that a company is coming to fit panels to my roof next week and they are going to use ClickFit?

 

[SRE]

It wouldn't be my choice, but I think you can be reassured that if Worcester is using it - it meets all necessary requirements. He's a chartered engineer and will have reviewed all relevant issues in microscopic detail. Building Control officers rarely have an engineering background and tend to get the wrong end of the stick regularly. They have just had to repay numerous Building Control fees to customers as a result of a mistake made (in good faith) by BC officers.

 

[Fitstart]

Thanks for the reply, that has eased my concerns a little. I am in a fairly exposed rural spot in Scotland however. The installer assures me that it will be fine. House is mid eighties timber frame bungalow.

 

[SRE]

As long as you've had a structural survey and the surveyor has said it's fine you'll be ok. Make sure the information from the structural engineer is included in your handover pack when you get it and if you haven't had a structural survey - get another installer

 

[Fitstart]

No structural survey. Again the installer said it was not required.
Starting to get worried.

 

[SRE]

No structural survey. Again the installer said it was not required.
Starting to get worried.

Every job without exception should have a structural survey - it doesn't cost much in comparison with your overall spend. Insist on it or change your installer .... very shoddy approach not to have one done - high winds ... who will you fall back on if the roof can't cope with the windload?

We've just recently done a job in eactly the same situation as you - our structural guy rejected the roof because it was showing signs of splaying. One beam installation later (about £350 and a lot of swearing) and the customer had a roof suitable for the installation of solar panels. If he's gone with the other installers he'd invited round - all nationals - not one of them did any structural calcs - could have been a solar sandwich!!

 

[Fitstart]

I'll contact a structural surveyor tomorrow! - Install is supposed to be on Tuesday.

 

[SRE]

I'll contact a structural surveyor tomorrow! - Install is supposed to be on Tuesday.

Should be the installer that does it and pays for it. They will get it much cheaper than you will - if you're in a particularly windy area make sure they fit extra hooks on the top and bottom rows. We only ever have top and bottom row hooks @ 800mm and 1200mm in the middle.

 

[Fitstart]

Thanks I will also contact the installer and inform him that I want this survey done and we can negotiate how the fee is paid. I presume the VAT can be reduced to 5% if he organises it.

 

[SRE]

Yes it should be all part of your install costs.

 

[solarsavings]

Every job without exception should have a structural survey - it doesn't cost much in comparison with your overall spend. Insist on it or change your installer .... very shoddy approach not to have one done - high winds ... who will you fall back on if the roof can't cope with the windload?

We've just recently done a job in eactly the same situation as you - our structural guy rejected the roof because it was showing signs of splaying. One beam installation later (about £350 and a lot of swearing) and the customer had a roof suitable for the installation of solar panels. If he's gone with the other installers he'd invited round - all nationals - not one of them did any structural calcs - could have been a solar sandwich!!

Splaying? not heard of that before in relation to a roof structure. What does it mean and how did a beam fix it, I'd be interested in the answer.

 

[SRE]

Well with the caveat that I'm not a structural engineer, from what I understand, houses built in the 50's and 60's have roofs that are at the edge of their tolerance and potentially the extra weight could essentially make the roof cave in. In this instance the roof was at the edge of it's tolerance and by putting the beam in the full length of the building it tied everything into the structure - but as I said - I'm no structural engineer, that's we bring the pro's and their professional liability insurance in.

 

[solarsavings]

I can't picture how a roof would splay so perhaps that's why I cant see how a beam would prevent/cure it. Are we talking timber beam? Where and how was the beam fixed in place.

 

[SRE]

Sorry not much help - it was a metal beam and I think it was anchored in the walls but tbh I could be talking a load of rubbish cos I didn't see it when it was done (I don't do the installs my partner does). Our structural engineer did the drawings and calcs and the customer followed what he's instructed and had it passed by BC.

 

[solarsavings]

OK thanks anyway.

 

[MorganPVI]

So what ratio of installs requires remedial action? 1 in 25?

 

[SRE]

Seems to depend on where you are in the country - about 10% of ours have needed work, but I've seen a structural engineer on this froum saying that 50% were failing. I think he was getting a bit carried away!!

 

[t4sltd]

I'm not a structural engineer but work with qualified roofers. The problems I would worry about are the roof collapsing under additional weight / down-force due to the roof slipping off the wall plates. I would never fix to a batten and I'm pretty sure all of my roofing friends would advise against it.

 

[Worcester]

Well I am a Chartered Civil and Structural Engineer, and it's not friends advice I take, it's professionals.

I have a 20 page confidential report that has been prepared on the problems associated with the current mounting systems, and I also know that there is a new MCS certification being drawn up that all mounting systems will have to comply to with and be certified before they can be used.

As a company we are developing mounting and fixing systems, that are fully compliant with the new standards, and are working with a number of the existing providers to help them develop compliant systems, you'd be quite amazed at what can actually be achieved, however until the spring, my lips are sealed!

 

[SRE]

So until Spring when your lips become unsprung - what's the best course of action for us mere mortals?????