Solar Limpets

[Gavin A]

@Gavin A, you should watch the video of a hanger bolt when doing the wind and snow loading tests on any roof material. I've witnessed many tests of materials, loadings and fixings in test labs that accurately represent real world conditions, and it's scary what happens to the whole lot (they test them to failure)

I'd be interested to see that video if you have a link.

I'd be surprised though if any wind or snow loading on any individual bolt is worse than our installers using them to stand on while working on the roof.

 

[ktech]

I'm purchasing solar limpts for two jobs. One is going in next week. So will report back on how it goes. Service from the supplier seems excellent. They have offered to come to the first job and show us how it's done. At no charge! So I guess they have confidence in the product.

 

[Worcester]

Just finished the 10kWp job, limpets went in fine, overall much less hassle than cutting, grinding tiles, and like the fact that no gaps at all left at the end. We used K2 medium rail (have more than a few lengths in stock from our more usual type of commercial installs) so we set the brackets at 400 / 800 on the bottom rail corners of each row and then spaced at 1200. Also staggered the brackets to get an even rafter loading. Would definately use then again.

P.S. because we spaced at 1200 and had budgeted for 800 we've got about 45 or so left over so if anyone needs an odd number (they sell in boxes of 25 we're happy to split) drop me a pm.

Also we put an extra row in at the bottom which we later removed to to act as the first staging point for putting the first row of rails in. It didn't tkae a lot longer and definately saved a lot of broken tiles (these were a weird 11" x 7" size) so by not breacking many, and taking out for spares more that 80, we were also able to replace all the existing broken tiles (there were quite a lot before we started) the customer also has a pile of spares for other parts of the roof.

Carl from Solar Limpets came out and spent an hour or so going through the best way to insatll them and passed over a few tips to make life easier, by the time he'd left they'd put in the brackets for the equivalent of a normal 4kw install!
One neat idea was to use an additional limpet for the cable entry.
(We replace any broken tiles as they place the panels just in case any others get broken during that process)

 

[The Solar King]

I am looking at these as well. Karl kindly sent me a sample so my roofer can have a look. Like Worcester, I am maybe a little uncomfortable over the slate mounting, but went to look at a job today that would be ideally suited to this route. Slate roofs in Scotland are a nightmare as the slates are nailed directly to the close boarding (sarking) with no battens. You can easily end up using several hundred pounds worth of lead for soakers and flashing on a 4kW install. The alternative is hanger bolts through a lead flashing sealed up with lead mate or some form of roof integration. None of this is cheap so the method suggested by Solar Limpets is very seductive.

I understand from Carl the product is undergoing full BBA approval, which is beyond that required by MCS012. If they approve the product for use in this manner on slate I will be a happy bunny as life will get a whole lot easier.

Interested to know what others think.

 

[SolarCity]

Gordon, that looks great.

I will probably wait until the BBA approval comes. If that comes then I'll be giving them a blast.

 

[ktech]

Following on from previous post; Clive came with us site - in the pouring rain. Very well explained system. Clive spent a good amount of time letting us know about the system and demonstrated the way to fit.
100% this method means no more roof ladders or expensive lead and is a 100% system effective for PV mounting. We will stick with it on any slate roof. What more can I say!

 

[dansk]

doing my first limpets next week, they arrived the other day and got to say they feel like a strong bit of kit.

 

[ktech]

The die hards might want to stick to slate with £150 + of lead and untold hours of labour but for us this is a quicker solution for slate and actually a faster fit than normal tiles + the end solution is excellent for the customer. We will no longer be charging a premium for slate installs that we have done in the past. Win win all around.

 

[whinmoor]

Do the limpets come with rail and all the mounting kit? If not, what rail did you use?

 

[dansk]

mine didnt, we use renusol with upright brackets on the limpets

 

[Worcester]

Here's their website: Solar Limpets-roof hooks-solar pv-solar installation-slate roof hook - Home Page

They are 'just' the roof hook, the straight bracket works for side fixed rails, the 90 degree angled bracket works for bottom fit rails, both portrait and landscape and also for side fix rails in landscape (rails up the roof) with a stainless steel adapter bracekt.

 

[dansk]

Worcester - All arrived ok the other day, never got time to say thanks

 

[zeljuga]

We used Limpets first time in May on 10kwp job. Carl came or round and guide as trough. Good time saving product.Our Joist finder Bosch D-tect 150 did not give good results, so in the end on Carl suggestion cheaper detector prove to be much better choice for job.

 

[dansk]

ohh - which one?

 

[zeljuga]

Bocsh 120 gsm ,spot on for job.