Slate hooks vs. limpets?

sharpener
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Slate hooks vs. limpets?

#1

Post by sharpener »

I have two potential suppliers for the kit on my slate roof. One is suggesting "slate hooks", which AIUI hook over the battens and the slates are then put back on top. The other is offering "slate limpets" which he says screw through the slates from above and are sealed with CT-1 mastic. Neither sounds to me like the perfect engineering solution.

Does anyone have any experience with either system that they are willing to share?

TIA
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spread-tee
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Re: Slate hooks vs. limpets?

#2

Post by spread-tee »

The hooks don't involve drilling holes in the slates and using mastic to bodge a repair. If you have a friendly roofer removing and replacing a few tiles is not a lot of work, or you could DIY if you are confident at height.
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Petertc
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Re: Slate hooks vs. limpets?

#3

Post by Petertc »

When we did a slate roof , we used hooks and solar slates for the flashing, made the job easier and looked good as well.
I have a feeling that back then 7 years ago, solar slates would only sell to businesses not individuals. That may have changed, or it might have been to do with the discount ? A lot of water under the bridge since then :D
sharpener
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Re: Slate hooks vs. limpets?

#4

Post by sharpener »

Petertc wrote: Tue Oct 04, 2022 6:37 pm When we did a slate roof , we used hooks and solar slates for the flashing, made the job easier and looked good as well.
I have a feeling that back then 7 years ago, solar slates would only sell to businesses not individuals. That may have changed, or it might have been to do with the discount ? A lot of water under the bridge since then :D
When you say "solar slate" do you mean something like this? https://www.gb-sol.co.uk/products/pvslates/default.htm
They are much more expensive/kW than ordinary panels.

Or do you mean something that covers the hook and makes good the gaps, in which case could you post a link if you can find it @Petertc?
16 x 230W Upsolar panels S Devon, 4kW Steca, 3.9 MWh FITs/yr
8 x 405W Longi panels, 250/60 MPPT, 3.3 MWh/yr
Victron MultiPlus II-GX 48/5000/70-50
10.65 kWh Pylontec Force-L2
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spread-tee
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Re: Slate hooks vs. limpets?

#5

Post by spread-tee »

I thought the idea of using hooks was that you don't need any flashings as there are no penetrations through the slates?
That's how we do it anyway.

Desp
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John_S
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Re: Slate hooks vs. limpets?

#6

Post by John_S »

sharpener
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Re: Slate hooks vs. limpets?

#7

Post by sharpener »

spread-tee wrote: Wed Oct 05, 2022 9:09 am I thought the idea of using hooks was that you don't need any flashings as there are no penetrations through the slates?
That's how we do it anyway.

Desp
Any chance of a link please?
John_S wrote: Wed Oct 05, 2022 9:45 am These things?

https://www.solarslateplate.co.uk/
Looks a much better engineering solution, but expensive? What if the rafters are not under the middle of the slate as shown?

The solar limpet installation videos here https://www.solarlimpets.co.uk/ make it clear it is a product designed for rosemaries and the slate application seems an afterthought, the method for locating rafters looks a bit hit-and-miss as well.
16 x 230W Upsolar panels S Devon, 4kW Steca, 3.9 MWh FITs/yr
8 x 405W Longi panels, 250/60 MPPT, 3.3 MWh/yr
Victron MultiPlus II-GX 48/5000/70-50
10.65 kWh Pylontec Force-L2
zappi 7kW EVCS
Villavent whole-house MVHR
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spread-tee
Posts: 604
Joined: Mon May 31, 2021 7:16 pm
Location: ville of spiky things

Re: Slate hooks vs. limpets?

#8

Post by spread-tee »

Our roofer has used these, or something very similar, he gets them from his usual supplier to order.

https://voltaconsolar.com/solar-panel/p ... VGEALw_wcB

He normally slides a few tiles up so he can see the rafters and battens then fixes the hook to preferably the rafter, or if not to the tile batten. Then we fix a nogging between the rafters inside the loft to support the batten. Once he gets the ladders up it doesn't take long

Desp
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Petertc
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Re: Slate hooks vs. limpets?

#9

Post by Petertc »

sharpener
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Re: Slate hooks vs. limpets?

#10

Post by sharpener »

Thanks all, very helpful.
16 x 230W Upsolar panels S Devon, 4kW Steca, 3.9 MWh FITs/yr
8 x 405W Longi panels, 250/60 MPPT, 3.3 MWh/yr
Victron MultiPlus II-GX 48/5000/70-50
10.65 kWh Pylontec Force-L2
zappi 7kW EVCS
Villavent whole-house MVHR
5000l rainwater system
Vaillant 12kW HP
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