Integrated PV Fire Membrane

[Dan F]

Hi,

 

Has anyone used a fire membrane below an in-roof PV instlallation or know of a suitable product?

 

We plan to use REC Alpha panels as they seem to be a great option from a price/performance/warranty standpoint.  We also plan to use GSE trays for in-roof integration.

 

The issues is that for an MCS certified install the specific GSE tray and panel combination needs to have been "BroofT4" tested.  Due to COVID the planned testing of this tray/panel combination hasn't yet been completed. Given this, we either need to switch to a different panel, or do what MSC012 says which is:

 

Quote

An alternative means for an installer to achieve a fire rating is to use a substrate with an independent fire rating (for example a barrier material with AA rating) beneath a roofing kit/module combination that does not have a declared fire rating. It is important to be able to verify that the system achieves a sufficient rating as a whole.

 

Sounds fairly easy solution to be able to use the panels or our choice, but the PV installer doesn't want to do this (they don't have expertise apparently), and it seems that finding a suitable membrane isn't that easy as a lot of them are only designed for internal use or specifically for verticial or horizontal applications and not for a pitched roof.  Also, while the PV installer seems happy enough to certify the install even if they don't supply/fit the membrane, our main contractor isn't that keen on this arrangement given potential grey lines around who designed and approved suitability of the fire membrane.

 

Any thoughts?

 

 

 

 

[dpmiller]

how much is the MCS cert worth to you?

[Dan F]

1 hour ago, dpmiller said:

how much is the MCS cert worth to you?

A must as it is mandated for SEG (paid export) and we'll be exporting a lot in the summer.

[Dan F]

Found a suitable product called "THATCH FLEXI" and have managed to convince PV installer to install this as part of their work.  It's a shame, as it adds an additional cost when the fire certificate is due in a month or two, but we can't delay on the panel installation and untested panel/tray combination, without fire membrane, means no MCS certificate and in turn no SEG payments from what I understand.

 

Now just need to work out if it's best to put the membrane under or on-top of the counter-battens:

- Under:  Less roof ventilation, 25mm PV panel ventilation, potentially harder for the PV installer to do at same time as the trays.

- Over:    More roof ventilation, almost no PV panel ventilation, easier for PV installer to installer under trays.

 

 

 

Edited September 10, 2020 by Dan F

[joth]

8 hours ago, Dan F said:

Found a suitable product called "THATCH FLEXI" and have managed to convince PV installer to install this as part of their work.  It's a shame, as it adds an additional cost when the fire certificate is due in a month or two, but we can't delay on the panel installation and untested panel/tray combination, without fire membrane, means no MCS certificate and in turn no SEG payments from what I understand.

 

 

Blimey you must be cracking on! Last I saw you had just done the ground slab pour?

by contrast we started renovating in Jan, yet we still seem to be 2+ months away from the panels being installed. 

 

btw interesting question about the fire cert. I've not heard mention of this at all -- ask me in a few months if we actually get the cert.

 

Edited September 11, 2020 by joth

[Dan F]

6 hours ago, joth said:

 

Blimey you must be cracking on! Last I saw you had just done the ground slab pour?

by contrast we started renovating in Jan, yet we still seem to be 2+ months away from the panels being installed. 

 

Yes, I'm behind on the blog posts, but MBC are almost done.. just putting roof membrane on and fixing a few issues this week.

 

6 hours ago, joth said:

btw interesting question about the fire cert. I've not heard mention of this at all -- ask me in a few months if we actually get the cert

 

You can read more about this here: http://www.windandsun.co.uk/products/PV-Mounting-Structures/GSE-Integration-Roof-Integrated#.X1uJ3JNKjUY

 

But, for MCS certification you need a fire tested panel/tray combination or a AA rated fire-proof substrate.  You weren't going to use GSE though were you?

 

 

[joth]

16 hours ago, Dan F said:

for MCS certification you need a fire tested panel/tray combination or a AA rated fire-proof substrate.  You weren't going to use GSE though were you?

 

GB sol RIS, so no tray as such just an aluminium frame. These are only ever used together so presumably the fire test was done years ago and isn't much of a thought now. 

[Dan F]

@joth Right. I forgot to get a design/quote from GB sol, for some reason i assumed they just did the ov slate. Cau you share any data on price/watt and watts/m2 for panels only?

Edited September 12, 2020 by Dan F

[joth]

1 hour ago, Dan F said:

@joth Right. I forgot to get a design/quote from GB sol, for some reason i assumed they just did the ov slate. Cau you share any data on price/watt and watts/m2 for panels only?

They don't really do panels only, but they were about 1.2 £/W including inverter for a part roof RIS supply only, jumping up to almost 2 £/W for a full roof including installation (and it took some negotiation to get it down to that price). The full roof is extremely specialist as the frame and panels have to be made _exactly_ sized to fit so they're pretty reluctant to provide it supply only. Also the aluminium frame is very unforgiving of the slightest undulation in the roof. Altogether a terrible choice for a renovation as we're now finding ?

[Dan F]

@joth We are at £1.30/W including installation (including fire membrane!!) with a solaredge setup (optimizers, 3-phase inverter and consumption monitoring) and all-black REC Alpha panels.  So quite good vs PV Sol RIS seems, only thing that not great about the standard panels is we have hipped roof so never going to look at good a gb sol setup designed for the roof shape.