Fitting of GSE in roof system

[Barryscotland]

 

Our roof is slate straight onto sarking, do I need to put down a frame for the GSE frames to sit on to allow the linking of the panels and ventilation to the panels or can I mount straight to the sarking and  drill into the Coombe of the roof for cabling?.  Anybody done a guide to the installation to keep us right? Its an 8 panel system, 2 rows of 4

[Conor]

Ideally, you'd have no sarking where the trays are going and instead use 100mm battens as per the guide. You really need the back of the trays to be ventilated. But I can't see why you couldn't directly fit the trays to the sarking boards. It would make fitting them a lot easier!! You cant raise the area up as the trays need to sit at the same height as your slates. Do you have optimisers or micro inverters? In which care you'll definitely need the ventilation gap.

 

 

Edited October 7, 2021 by Conor

[Barryscotland]

I'd thought if I made a frame from 25mm tile batton it would get it up enough to run the cables and wee bit of ventiliation to the panels, Then put a bend to suit the extra height in the lateral flashing. Would be alot easier to mount it straight onto the roof tho.

[Conor]

Nope, won't work, you'll never get the flashing to work and it'll look wrong. Either have to strip sarking away in that area or fit directly.

[Barryscotland]

26 minutes ago, Conor said:

Nope, won't work, you'll never get the flashing to work and it'll look wrong. Either have to strip sarking away in that area or fit directly.

 

If I strip the sarking away I'l be left with nothing but trusses and a giant opening straight into my attic space. Will speak to company that suppled the kit and the roofer, see what they recommend

[Barryscotland]

Our kit didn't come with top or bottom metaL flashings just a roll of roofflex 330mm wide flexible sealing strip and a roll of deks fast flash 280mm wide. Anybody else use this instead of metal flashings? Which goes top and which bottom?

[Dave Jones]

4 hours ago, Barryscotland said:

Our kit didn't come with top or bottom metaL flashings just a roll of roofflex 330mm wide flexible sealing strip and a roll of deks fast flash 280mm wide. Anybody else use this instead of metal flashings? Which goes top and which bottom?

 

metal ones on top, try and position it so the tile cuts work at the top. bottom is the stickable flashing so have more leeway.

 

I ran a length of 450mm damp under the top and bottom flashing to belt and braces.

[JohnMo]

Take it you are in Scotland, I fitted GSE trays, tried to follow the instructions and they made little of no sense when working with sarking boards.  If you add additional timber on the sarking the finished roof looks rubbish as nothing aligns correctly with the slates/tiles.  The additional ventilation gives you a little uplift in performance, but not much to worry about.  Screw them direct to sarking boards and make life easy.  I had metal flashing at top and sides, flex stuff at bottom.

[Dave Jones]

The GSE kits do work pretty well, they are let down a bit by the rubbish stick on flashing though. 

 

nice roof, the slate to metal transition looks very well done.

[Barryscotland]

On 19/10/2021 at 23:08, JohnMo said:

Take it you are in Scotland, I fitted GSE trays, tried to follow the instructions and they made little of no sense when working with sarking boards. 

yes in Scotland, we ended up fitting straight onto sarking ignoring the advice of the seller but couldn’t see how it would work any other way.

 

does anybody no if the install needs to be certified by a solar person or is it just signed of with the rest of the electrical stuff? New build in Scotland

 

[JohnMo]

My electrical contractors are signing off as part of the overall electrical cert.  They don't have a solar person so to speak. 

[Thorfun]

On 20/10/2021 at 07:24, Dave Jones said:

The GSE kits do work pretty well, they are let down a bit by the rubbish stick on flashing though. 

 

nice roof, the slate to metal transition looks very well done.

our solar PV company sent us photos of lead flashing details for the GSE trays.

 

 

the roofer said no problem and will be using Code 4 300mm lead flashing so we're going that route.

[JohnMo]

I was on my roof this afternoon, sticking the rubbish corrugated flashing back on as it was starting to lift at one end.  The lead flashing looks very tidy.

[joth]

21 hours ago, Barryscotland said:

does anybody no if the install needs to be certified by a solar person or is it just signed of with the rest of the electrical stuff? New build in Scotland

 

Standard electrician sign off is fine, unless you want to sell back any surplus to the grid (https://solarenergyuk.org/resource/smart-export-guarantee/) in which case it needs MCS sign off (which generally only comes as part of a supply & install package).

 

 

[Barryscotland]

That’s good news, was expecting to need another piece of overpriced paperwork.

 

last question, probably a stupid one, we haven’t got mains power into the house other than an extension lead from the caravans supply. Should we leave the panels unconnected or can we wire up the inverter even tho any power produced has no where to go? 

[joth]

So this temporary extension lead is hooked into the new house consumer unit? No do not connect the PV inverter as it'll try and export it's load back up the 13A extension lead.

And even if not, I think you're better leaving the inverter disconnected until a qualified electrician is there to commission and sign it off.

Also, in case you're not aware, be careful about the high voltage DC from the PV panels if you're leaving them unconnected that side of the inverter. 

Edited October 24, 2021 by joth

[Dave Jones]

On 24/10/2021 at 11:16, Thorfun said:

our solar PV company sent us photos of lead flashing details for the GSE trays.

 

 

the roofer said no problem and will be using Code 4 300mm lead flashing so we're going that route.

much better solution and nicely done as well.

[Dave Jones]

On 19/10/2021 at 23:08, JohnMo said:

Take it you are in Scotland, I fitted GSE trays, tried to follow the instructions and they made little of no sense when working with sarking boards.  If you add additional timber on the sarking the finished roof looks rubbish as nothing aligns correctly with the slates/tiles.  The additional ventilation gives you a little uplift in performance, but not much to worry about.  Screw them direct to sarking boards and make life easy.  I had metal flashing at top and sides, flex stuff at bottom.

 

interesting scaffold bench supports on the roof, what are they called ?

[JohnMo]

No idea what they are called, but all the Slater's here use them (NE Scotland).  The support for the scaffold board in knocked into the sarking board under a removed (or not installed) slate.  It think they would only work with sarking boards

[Thorfun]

52 minutes ago, Dave Jones said:

much better solution and nicely done as well.

just to avoid confusion that photo was sent by the M&E company and is not my roof, but I hope my roofer can do as nice a job! I have full faith in him as he comes highly recommended and I've seen his work so it should look great. 

[JohnMo]

On 24/10/2021 at 19:37, Barryscotland said:

last question, probably a stupid one, we haven’t got mains power into the house other than an extension lead from the caravans supply. Should we leave the panels unconnected or can we wire up the inverter even tho any power produced has no where to go? 

For reference, our panels were on the roof for about 7 months, before being connected to inverter.  We had them wired to the DC isolation switch, which was switched off.

[SteamyTea]

You can install the complete PV system and just use the two isolators to disconnect the AC and the DC sides.  It is what they are there for.

I think you can get locks for them as well.

Always disconnect the AC side first.  Don't isolate on the DC side as that can cause arcing in the switch.  Ask our old electrician about this, dopey pillock.

[SuperJohnG]

@JohnMo @Barryscotland

 

I've been trying to figure out if the GSE trays could sit directly on sarking (I actually have sarking them 25mm ventilation then sips roof. So found the answer here thanks!

 

All been ok with both your panels just as you'd mentioned the ventilation thing there. 

 

I'm in Scotland also and just considering ripping off my slates to fit PV panels...which I wish I'd done before getting it slated last year. doh.

[JohnMo]

We have a 3.1kW if panels installed and saw 3.05kW being generated, so no issue with mounting direct to sarking boards.

 

I did quite a bit of research before mounting direct to sarking boards.  Everything I read led me to the conclusion that in Scotland, it's not an issue with overheating, and if there is an issue your performance drops while the panels are too hot.  Southern England may have an overheating issue, but they get better PV production.

[Jenki]

Resurrecting an old thread as it seems a good fit.

 

I'm looking at ordering my trays now, its going to be 2 rows 5 columns of panels  (10).  and trying to work out the flashing required.  

1: The instructions suggest top flashing is not usually required as the tiles overlap the gse tray.

2: Bottom flashing, I have the option of having the bottom of the panels at the gutter edge. if I were to do this the gse tray would overlap the felt support tray, so would flashing be needed here?

 any thoughts on this?