Building regs - correct position of panels on roof

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rabnudj

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Hi,

I'm having a new roof on my house and am forced to organise fitting the panels myself because the solar firms are hopelessly backloged. So I've been doing lots of research, but there is one element that I can't get my head around.

My house is a semi detached with a hipped roof facing south effectively a triangular surface for panels. It's 9m along the bottom edge, so not super large area, so I really want to squeeze on as many panels as possible.

Various websites quotes there rules

#Not be installed above the highest point of the property (not including chimneys)
#Be fitted in a way that least affects the external appearance of the property and the surrounding area
#Not protrude more than 200mm from the surface of your roof

I would like to mount panels sitting level with lowest tiles and the top of array touching the hip (and mounted close the a roof window) ie, really maximize roof space.

My interpretation of these regulations suggests I can do this. Any comments would be very welcome.

James
 
If you mounted the panels on the bottom row then the rain would run off them and go right over the top of your gutter, pretty certain there is a rule or guidance on top and bottom limits to panels, sure I read it but just can’t recall it, I am sure a clever person will be along just shortly to give you the info.
 
It's recommended that the panels are roughly 200/300mm away from roof edges, for wind loading issues. However with a hipped roof, it's not a problem to have a corner of a panel on the diaganol hip ridge.

Make sure you get the roof hooks fitted before the roof covering goes on, or at least the ridge tiles Hipped roofs are a pain in the neck to get the roof hooks in once the ridges are on.
 
It's recommended that the panels are roughly 200/300mm away from roof edges, for wind loading issues. However with a hipped roof, it's not a problem to have a corner of a panel on the diaganol hip ridge.

Make sure you get the roof hooks fitted before the roof covering goes on, or at least the ridge tiles Hipped roofs are a pain in the neck to get the roof hooks in once the ridges are on.
Thank you -This is very helpful, sounds like the voice of experience.

If you are able to reference this information from an official source I'd be extra greatful
 
Thank you -This is very helpful, sounds like the voice of experience.

If you are able to reference this information from an official source I'd be extra greatful

Its in the MCS installation guide if you can find a copy on-line. However, there's some deabte about the edge gap, some say this is not needed as long as you have sufficient roof hooks. I'm not sure I would totally agree with that, but finding guidance on how many hooks extra you would need is nigh on impossible. Biggest problem when retrofitting is the fact ridge tiles are mostly cemented in place, so ripping slates or tiles without damaging the cement is very hard to do.

The link below should give you some idea of what you need to do, only trouble is panels are notably bigger these days, albeit higher efficiency, so getting as many panels on the roof is not so easy. Note the all black array - not one of mine, has been designed for easy installation :D

Given that you are fitting a new roof, it maybe worth looking at the GSE in-roof mounting system, it's so much neater. https://www.gseintegration.com/en/solutions/gse-in-roof-system/

https://goo.gl/maps/DPta9Xck9qL5GWh86
 
Thank you again for your long reply. I'll take a look at the MCS guide.

I'd already written off the GSE in roof system, as I don't like the idea of the roof being build around a specific panel, not sure what would happen if you needed to replace a panel or whole array in the future. To be honest, I'd not even looked into it at all, but can't deny it looks much nicer.
 
Thank you again for your long reply. I'll take a look at the MCS guide.

I'd already written off the GSE in roof system, as I don't like the idea of the roof being build around a specific panel, not sure what would happen if you needed to replace a panel or whole array in the future. To be honest, I'd not even looked into it at all, but can't deny it looks much nicer.
whatever you fit now will not be directly replaceable in 30-35 years time Panel sizes keep changing, with the current trend to being much bigger than those in the link I posted. Panels are pretty reliable, so I wouldnt worry about them, and if you have to replace the whole array you can always recover the roof and use on-roof mounting. The nice thing about in-roof is you can go right down to the roof edge as per this photo. NB don't use the metal top flashings, they are suppossed to aid ventilation, but frankly are crap, just use flashing across the top.
 

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Ok, I am see the advantage. Unfortunately I'm my case, I won't be able to lay panels out in a neat reactangle area, I'll be needing to add them in a more adhock arrangement which I'm sure in-roof would not suit
 
Ok, I am see the advantage. Unfortunately I'm my case, I won't be able to lay panels out in a neat reactangle area, I'll be needing to add them in a more adhock arrangement which I'm sure in-roof would not suit
Hasn't got to be a rectangle. Read the installation instructions.
 
The attached should help.
Downloaded from MSC website
 

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  • MSC MIS-3002_Solar-PV-Systems-V4.0.pdf
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Ok, I am see the advantage. Unfortunately I'm my case, I won't be able to lay panels out in a neat reactangle area, I'll be needing to add them in a more adhock arrangement which I'm sure in-roof would not suit
Why don't you post photos or sketches in order for us to understand better?
 
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