Roof anchors

[SRE]

It's sealed underneath with a roof sealer that stays semi fluid. So the flashing sits on a sort of floating seal - our roofers are working on slate every week that's why we subcontract them and that's the way it's done by the professionals. We had 2 slate roofs in a week - don't want to see another for at least another couple of weeks!

 

[d1ssc]

Using a lead flashing with slate imo is the only way to do it right, being a roofer i strongly wouldnt advise drilling thro the slate and trying to use sealant. These anchors that go thro the slate with the rubber washers wont stay watertight for long if even atall and they will perish with the weather, any movement or probibly just trying to tighten them up will crack the slate...... wasnt very impressed that on the pv course they were advising using these types of anchors!!!

 

[d1ssc]

Sorry to be goin on but we would have had the lead up under the slates in your picture, then they wouldnt need sealed, it would be just like fitting a vent or a flue pipe, ive took a lot of good info from reading on this forum, being a non spark hopefully this might help some of you guys back!

 

[SRE]

No worries about going on about something - we're all learning from each other. Our roofers have been doing this for over 20 years but it doesn't mean it's the best way. I'll tell them what you said, I seem to think there was a good reason for not doing it this time but I can't for the life of me remember what it was.

 

[Worcester]

No need for sealing if it's done properly, this is an example using the Azur fixing.

Also there really should be very little lead left showing when done properly.

Check out these actual install pictures: https://picasaweb.google.com/worces...authkey=Gv1sRgCJz0hr728c_EqgE&feat=directlink

Gordon

 

[SRE]

We had real trouble getting the Cambrian slate out to cut it - any suggestions how we could get it out without breaking every slate? It's held onto the roof with 2 pins rather than normal nails. That's why we decided to use so much lead but leave the existing slate in place. Otherwise it was going to be 70 replacement slates as well as the 10 we broke during the installation - it was like treading on eggshells!

 

[Worcester]

On Slate we ALWAYS use professional roofers, that have a special knife / gizmo called a "Slaters Ripper" ( Toolstation > Digital Catalogue) that slips under that tile and cuts through the pins - nails SHOULD be copper / aluminum, occasionally we've come across bodged jobs where they've used galvanised nails and they can be a pain to remove, patience and experience!

The nails you see the guys putting back in are Aluminium NOT galvanised ..

ALso trimming the slates is done with a specialist tool (http://www.toolstation.com/documents/catalogue/catalogue38/catbox.html?pg=143&code=92704) that nibbles away at the slate and also punches the new nail hole without breaking the slate.

Without expection, we send ALL our new guys away on the PV Installtion course run the REAcademy (Solar Panel Installation Training from Renewable Energy Academy, Specialist Training Providers in Renewable Energy Installations) the same guys that run the Sharp Academy (Sharp Renewable Energy Academy - Sharp) , the courses are expensive, however it pays itself back on the first job with improved safety, more efficient jobs, less mistakes / repairs etc

Gordon

 

[SRE]

Yep we also always use professional roofers for every job not just slate, the slate ripper just doesn't work with Cambrian slate, it's fine with the others. Our guys have worked on slate roofs in a national park for the last 20 years and are very experienced.

Unfortuntaley Cambrian slate is very different to all of the other types of slate we've dealt with. Most slate is pretty straightforward to sort out with the aid of the usual slate ripper. The problem with the Cambrian slate is that you don't actually put nails into the slate as with other types of slate. It has a plastic lip that the slate sits on and it's the nails (which are more like screws and twice the normal length) that are the problem - they can't just be pulled off in the usual way with the slate ripper and even with patience and 20years experience they don't come off well. The guys who manufacture the slate actually re-roofed as there was a fault with the roof and they couldn't get the old ones off without breaking them.

It never ceases to amaze me how many installers don't use experienced roofers, but we're not one of them, the slates even beat the manufacturer!

 

[Worcester]

@SRE,
Don't know if this will help for the future, fourtunately we haven't come up against those (yet)

Cambrian Slates Repair Instructions:
http://www.monier.co.uk/fileadmin/b..._Repair_Kit_-_Fixing_Instructions_Shawell.pdf

Gordon