Fixing to new slate roof

[BruceB]

I quoted and got a job to put solar pv and thermal on a (demolish and) new build with straightforward interlocking concrete tiles. However I have had an email mentioning in passing that they have changed to Marley Duo Edgemere interlocking slates! I have used Schuco anchors to date on other installations. Anyone know the best one to use for this? Schuco make a slate anchor and a plain tile anchor, but I cannot get my mind around how they work. It appears the slate one actually lies on top of the slate, which seems wrong making a slate loadbearing. Or have I misunderstood? Do we do our roofs different from the Germans, because it looks to me like standard concrete tile anchor would work.
Regards
Bruce

 

[funboy57]

Why would it be load bearing. Use the Shucco fixing with the neopene gasket, pilot hole the slates with a dill bit not on hammer slightly over sized than the screw your using. Apply mastic to hole, screw the slate anchor down but just pinch up at first, then manually use screwdriver to bite down a bit more, your are fixing to rafter, noggin or what ever, do not over tighten or you will crack the slate, job done. I done a few like this, they have lasted through last years snow etc. no problem.

 

[Solus Direct]

Hi Bruce,

We are a Solar PV wholesaler of Schuco and other makes of brackets. The slate bracket is a little awkward and the best way is to cut out the slate over the rafter, fit the bracket and lead flash over it.

Funboy57 is right, the best way to do it is with an hanger bolt and drill through the slates into the rafter. The majority of our customers do it that way and have had very few problems.

Let me know if you need any help on this

Mark
Solus Direct

 

[BruceB]

Well you may be right that is the best method - I know a few on here have recommended it. It just seems a pity to be drilling holes in brand new slates if there is another way. What I was actually asking about was the Schuco slate anchor SCH-256313. I have tried to attach a picture.
Regards
Bruce

 

[SRE]

We do loads of slate and NEVER drill through it regardless of how old it is. Fix the anchor to the spar, take a notch out of the slate so it fits snuggly back on top and flash it in with lead. We always use experienced roofers they and our customers would be horrified at drilling through slate and using sealant to bung the hole up. I'm sure it's in the MCS info that this isn't regarded as good practice. Of course others will disagree

 

[funboy57]

Well each to there own I suppose, the mastic is not used to bung up the hole its there to provide expansion and contraction around the fixing screw/bolt. The bracket shown by BruceB has a neoprene gasket underneath it,THAT provides the water seal not the mastic.

 

[BruceB]

I had no idea the Schuco anchor I had shown had a neoprene gasket! Where do you know that from? Are there some installation instructions that mention it?
Regards
Bruce

 

[funboy57]

If that is the slate anchor it has a gasket underneath the flat side that fixes to the roof, the gasket is full length of the anchor which helps not only to seal around the fixing holes but provides some cushioning. How do I know? I`ve used them.

 

[MCS Renewables]

We use them as well.
They look like this.
Solar thermal installers have been using them for years with no problems.
You just need to be careful with drilling to ensure you dont miss the timber !
No sealant required for waterproofing but good for peace of mind.

 

[Worcester]

Would you do that on a £1m house?

And accept the potential liability?

 

[MCS Renewables]

Would you do that on a £1m house?

Yes and we have done. These approved fixings will not leak as opposed to cutting slates and bits of lead. They are designed for this purpose and are superb.

MCS registered since 1st April 2010, over 112 jobs on houses worth up to 5.4 million, no leaks yet !

probably get one tomorrow now ..... thanks !

 

[SRE]

The point is the leaks will come 4/5 years down the line not now. The constant wearing of the wind loosens the washers eventually and that's when the leaks happen. Our roofers have patched up quite a few of the solar thermals that were installed 6 years ago under a project that I used to run.

Last time I looked lead flashing was what most UK housing used to keep waterproof ....

 

[Worcester]

@SRE,

That's precisely my concern, I know lead isn't cheap, and I know baxi use a similar system.

Can someone show me the TUV or Building Research Labs test certificates, most building materials need that and more (Agreement Board), instead of colloquial, 'it works mate'. Show me the proper, tested, (freeze/thaw, hot/cold , wind/slack) results that simulate 25 years and I'll change my mind, untill then I reckon you're building up a massive potential liability, that no warranty clause will exclude you from.

I attended a recent MCS Inspection for a friend of mine, and the Inspector specifically asked to see the test certification for the mounting systems they used....

Good old Mississippi "Show Me" state..

This is your opportunity to convince me..

 

[Ecodan]

Hi,

I am new on here as well as to PV instalations. I am currently finalising my MCS instalation. I have the Schueco hanger bolts as recomended by some for my own slate roof. However the more I think about it the lead flashing seems the better option. Does anyone know which code lead to use or if anyone sells a preformed flashing?

thanks in advance

Dan

 

[DomB]

We've got our first slate job next week.

Our roofer said he'd prefer to cut out slots for for the anchors to fit into and then lead flash over them. The anchor distributor has said to use Code 3, 150mm lead, to have some lead sealent to hand and to cover the lead with patination oil to finish.