First off i’m not a roofer. However i’ve done new and repaired quite a few.

At a gable end i’d not be too worried so long as the edge is fairly square and i was using nigh on half a slate, it’s pretty obvious if things don’t look right, if you have concerns you could fit much wider soakers in code 3, which would probably be easier than using the thicker slates you’ve found. This does assume that the roof is not very exposed / subject to extreme weather.

If it were at a verge , i’d be trying to find slate and halves.

One company I worked for did a lot of re-roofing, and slate and a halfs were always mandatory to ensure water-tightness. Regular slates were never cut down by more than a few mm.

As Tom suggests, buy new if necessary - they will blend in after a few years.

Hi and many thanks for all the replies...

@Artiglio - "i’d not be too worried so long as the edge is fairly square and i was using nigh on half a slate"

The edge isn't square unfortunately. The wall itself bends like a banana, and being a stone wall it's not flat either (protruding stone)... Perhaps worse still, it won't be anywhere near half a slate. It's pretty much thin slivers of slate. I will go up now though and double check/take measurements, as it's a while since I've been up there to look.

@Artiglio - "if you have concerns you could fit much wider soakers in code 3"

Wider soakers is something I had been thinking beforehand as well, just to go the full belts and braces approach. So I guess without slate and a halfs, that becomes even more important. I was planning to use either 225mm or 240mm lead, with 75mm upstands, leaving 150mm or 165mm wide pieces on the slates horizontally. Would that be wide enough do you think?

@Artiglio - "This does assume that the roof is not very exposed / subject to extreme weather."

The weather can be quite extreme where we are, but luckily it tends to come from the West and this gable end is East facing as quite shielded.

@fostertom - "What's wrong with new ones, apart from cost(?)."

Tbh, I just hadn't thought of that as an option. But now that you've mentioned it and I've looked into it, it would definitely be the cot putting me off! The backside has 20x12 slates. I've found 20x18 (450x500mm) and the cheapest I've found is around £25 per slate! I'd be needing around 10. Seems that's the largest they do, so that would still leave me without slate and halfs for the front, which need to be 24x20 or thereabouts. I didn't spend a long time looking, so they might exist. But didn't find any on first look, and live in fear of what the price of those bessies would be!

@Mike1 - "One company I worked for did a lot of re-roofing, and slate and a halfs were always mandatory to ensure water-tightness."

Was that using new or reclaimed? I've been asking about, and tend to get a chuckle when I ask for reclaimed slate and a halfs in the sizes I need. Most say not a chance in hell, and some expand that they never used slate and a half back in the day, which is why they don't exist in the reclaimed world.

@revor - "A bigger slate could be cheaper than slate plus 1/2."

It certainly seems that way. The only problem being as I said in the OP - that huge slates tend to be a lot thicker.



I had another thread recently in which I asked about doing the flashing in Z shape, which horizontals over the slates. It wasn't a popular choice. But if I can't get any slate and a halfs, would that not help as an additional layer of protection to lessen the amount of water reaching the soakers in the first place? That coupled with the wider soakers as discussed above?

Here's a link to that thread for future reference:

http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17853&page=1#Item_23

Thanks again

Posted By: greenfinger@Mike1 - "One company I worked for did a lot of re-roofing, and slate and a halfs were always mandatory to ensure water-tightness."

Was that using new or reclaimed?

More reclaimed than new, but there are no doubt geographical variations in availability.

@cjard - "How far across the top of the slate are you thinking to run your flashing?"

I was thinking somewhere around the 100mm - 150mm mark. But having re-read the above, and looked into it some more, I'm wondering if perhaps scrapping that idea and sticking to just having the vertical flashing will suffice.


On a more general note, I think I may have mostly found what I need. I can get some slate and a halfs for the back of the house where the slates are a bit smaller. And I will try to cut the slates to roughly follow the contours of the wall.

For the front, I have now measured up... Using what I can get, in the worst case scenario the slate will stop an inch short, so leave an inch gap (maximum) between the side of the slate and the wall. ***Is this acceptable or an absolute no no?*** To help mitigate, I plan to use soakers with a 165mm width across the tops of the slates

Many thanks

Posted By: greenfingeris it ok to have a one inch gap between the side of the slates and the abutment wall?

I think that would provide adequate support, though ideally you'd space several of the adjoining slates to spread out the gap, unless the gaps between slates are already excessively wide.

However I'd also increase the width of the lead by 25mm to ensure adequate coverage - so a minimum of 200mm wide (125 on the slope + 75 up the abutment) instead of the usual 175mm.

Don't forget to carry the underfelt up the abutment, below the soakers.

Many thanks @Mike1 and @cjard for the helpful replies.

The issue with spacing out adjoining slates is that the plan was just to re-do the leadwork. As such I'm planning to strip a couple rows vertically. Stripping back more rows - to increase gaps enough to add up to what's required at the wall - would make it a much bigger job, which I'd really prefer not to.

Yes, sorry - I should have been clearer RE the lead for the soakers. I was proposing to get 240mm width lead, so 75mm upstand and 165mm on the slope.

Posted By: Mike1

Don't forget to carry the underfelt up the abutment, below the soakers.

Thank you. Yes, this was part of the plan but appreciate the reminder! Would you come up the wall with the felt the same amount as the soaker (75mm)?

Posted By: cjardThe smaller the gap is the more large wind-blown debris will be inhibited from coming to rest on the soaker, but that's about all I can think of for differences

Hmm... Interesting to note. We live in a wooded area with plenty of leaves, pine needles, and debris about! I guess I'll just have to add it to the maintenance list to keep an eye on it and brush it down as and when....


Thanks again

Thanks for that @Mike1 - all encouraging stuff to hear :) Sounds like I've got a plan then....