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What are the bureaucratic restrictions for PV on a flat roof?
Posted: Fri May 26, 2023 4:36 pm
by Smallholder
I'm trying to get a new PV system installed, on a flat roof. I'm about to apply for planning permission, but can't find any solid info online about restrictions in terms of how far from the edge the panels must be.
I assume this is a building regs thing rather than planning permission, but I'll need to be on the right side of both aspects I guess.
Many websites seem to refer to a general rule of panels being at least a metre from the edge, which for my roof will massively reduce the area I can use.
Does anyone else have any experience with this?
Thanks in advance
Re: What are the bureaucratic restrictions for PV on a flat roof?
Posted: Fri May 26, 2023 5:02 pm
by Mr Gus
There was recently a thread on the same matter, in that instance a shared run of garage roofing I think, have a dig around, (it had pictures also)
Re: What are the bureaucratic restrictions for PV on a flat roof?
Posted: Fri May 26, 2023 5:18 pm
by Mart
Hi, as a placeholder till people who know come along, the general advice for roof edges was 200-300mm. This avoids wind lift on the sides, and rain run off passing over the gutter at the bottom. For the top it's also to stop the higher (raised due to the mounting) PV panels actually be higher than the ridge tiles, which may then require PP as the height and look of the ridge will change ..... leading too ...
for a flat roof, the issue requiring PP may be that you are changing the look if the panels are sloped (typically with pitched mounts or weighted tubs). If the panels are fitted at the same pitch (flat), then it may be OK, but the flatter the pitch, the more the panels will need cleaning, and won't generate as much as say a 30d pitch .....
...... I think?
Re: What are the bureaucratic restrictions for PV on a flat roof?
Posted: Fri May 26, 2023 6:02 pm
by Smallholder
Mr Gus wrote: ↑Fri May 26, 2023 5:02 pm
There was recently a thread on the same matter, in that instance a shared run of garage roofing I think, have a dig around, (it had pictures also)
Thanks, I've had a bit of a dig around, but can't find anything. I'll search again tonight.
Re: What are the bureaucratic restrictions for PV on a flat roof?
Posted: Fri May 26, 2023 6:06 pm
by Smallholder
Mart wrote: ↑Fri May 26, 2023 5:18 pm
Hi, as a placeholder till people who know come along, the general advice for roof edges was 200-300mm. This avoids wind lift on the sides, and rain run off passing over the gutter at the bottom. For the top it's also to stop the higher (raised due to the mounting) PV panels actually be higher than the ridge tiles, which may then require PP as the height and look of the ridge will change ..... leading too ...
for a flat roof, the issue requiring PP may be that you are changing the look if the panels are sloped (typically with pitched mounts or weighted tubs). If the panels are fitted at the same pitch (flat), then it may be OK, but the flatter the pitch, the more the panels will need cleaning, and won't generate as much as say a 30d pitch .....
...... I think?
Many thanks, good to see reference to something less than a metre at least.
My current plan for the array is to have panels mounted at 15 degrees, which puts them over 200mm above the existing surface, hence PP required.
The concern being if I end up getting PP for the design, get it all installed, and then run into problems with building control. I'll try contacting building control and see if I can get any sense out of them.
Re: What are the bureaucratic restrictions for PV on a flat roof?
Posted: Fri May 26, 2023 7:40 pm
by Mr Gus
I also hopped through 50 pages & couldn't find it, the OP was talking of car solar (ie a 5 watt type thing originally installed, then put a full slightly angled array on, maybe they'll chime in.
mostly though it's saying 200-300 mm from edge.
Re: What are the bureaucratic restrictions for PV on a flat roof?
Posted: Fri May 26, 2023 8:02 pm
by MrPablo
I'll admit I didn't do PP for my garage array, taking the route of don't tell, don't make problems.
Could you take an alternative approach and potentially re-roof the garage with a pitched roof, then put solar panels on top?
It could liberate some useful storage space underneath.
Re: What are the bureaucratic restrictions for PV on a flat roof?
Posted: Fri May 26, 2023 8:19 pm
by Mr Gus
Bingo! it was Mr Pablo's pictures, certain there was another near then.
https://camelot-forum.co.uk/phpBB3/view ... 058#p20058
Re: What are the bureaucratic restrictions for PV on a flat roof?
Posted: Fri May 26, 2023 10:12 pm
by ecogeorge
Smallholder wrote: ↑Fri May 26, 2023 4:36 pm
I'm trying to get a new PV system installed, on a flat roof. I'm about to apply for planning permission, but can't find any solid info online about restrictions in terms of how far from the edge the panels must be.
I assume this is a building regs thing rather than planning permission, but I'll need to be on the right side of both aspects I guess.
Many websites seem to refer to a general rule of panels being at least a metre from the edge, which for my roof will massively reduce the area I can use.
Does anyone else have any experience with this?
Thanks in advance
Why are you going for planning ???
Anyone who complains just say its permitted development and let them prove different....
George
Re: What are the bureaucratic restrictions for PV on a flat roof?
Posted: Fri May 26, 2023 10:45 pm
by marshman
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