Wet verge on cottage

[Cottagedoup]

Hello new to forum.

We've just found ourselves proud owners a bunch of derelict cottages and are isolating onsite working away during all the madness. The cottages are stone rubble walls, we got the roof done up to the underlayer and are working on fixing the stone supporting the purlins, using nhkl3.5 for the building work.

My question is about wet verges. We're had to take the crumbling verges off and are replacing the rusted corrugated with natural slate. Can someone give me a breakdown on how to pour the wet verges for best results. I had assumed you'd lay the roof and then set up form boards and pour the wet vere over and round the edges, but some online info seems to say bed the slates in the mortar. I'm not quite sure if that's correct or what the workflow would look like doing it that way. I'm thinking of using nhl 5 and sharp sand for the verges. I've no Portland cement onsite and the shops are all closed up for the virus.

Any input or thoughts appreciated.

 

[Johnny Allround]

Hi Cottage, take some photos of the problem areas there’s people on here that will point you in the right direction.

 

[datarebal]

Nhl 3.5 bed the verge you don't pour anything. Normal good practice protect the lime from frost, rain and sun until a good set

of course assuming you created an over hang with the new slate?
or do you have cottages common in places like Donegal, tin roof with a concrete parapet gable?

 

[Cottagedoup]

So i hope these photos make some sense. I'm trying to figure out what's the working process for bedding the last row of slates in the lime mortar, as well as how far the slate should extend over the 2ft rock wall. Should the slates end where the purlins end (i.e half way across the wall) or should the battens extend the last set of battens so the slates cover the more of the stone wall.

The workflow question is this is guess. When i'm setting up the slates does it makes sense to start one or two slates away from the verge to get them set and running to the ridge, and then mix up a big batch of nhl 3.5 and set the slates that will be over the wall into a bed of mortar all the way from edge to ridge. i assume i'd come back later and set more nhl 3.5 on top of the slates and add the coping stones after they are set... or does that entire operation of bedding the slates and putting lime on top and setting the coping stones need need to happen at once.

The photo is not of my cottage but is what i am to achieve,

 

[Cottagedoup]

replying to detarebal, yes i've got something similar to what they do in donegal, way down south in west cork. instead of tin and concrete i've slate and limecrete.

 

[datarebal]

Ok, The photo you uploaded looks like the actual slate under the stone copings is actually slightly higher than the roof slate. Weathering wall to slate roof looks like it maybe a lead or zinc secret gutter. the slate under the stones is added weathering to prevent moisture soaking the wall. A dpc in fact.
so you could slate up to the wall using either a secret gutter or soakers , bed the dpc slate on top of the stone wall
I am just guessing from the picture.
I've done a few in Donegal removing the tin, reducing the wall height and slated over with an overhang as one might.

 

[Cottagedoup]

Thanks I've been able to clear things up a bit doing more research last night. I think it makes sense to do as you said and just slate over the wall and then either make up and embed some metal to clamp down every third slate as they do sometimes, or if the pandemic goes on for another couple months do some fancy stone copings over the slates.
I guess the only thing i'm still figuring is how far the edge of the wooden battens should be from the end of the wall. I'm guessing that just enough so that you can get a proper nail in the last slate.

 

[datarebal]

what size are the slates?
you can firm things up with some board in between the battens, it will give you a better choice of fixings

 

[Cottagedoup]

the slates are 250x500..
by some board in between the battens do you mean a board running up the roof perpendicular to the battens set under the battens on top of the wall?, or boards run in in plane with the battens running the same way, not sure i can picture it

 

[datarebal]

tight up under the battens. They will strengthen up the verge which will be a little vulnerable to wind damage. unless you use slate and halves?

 

[Cottagedoup]

ahh grand yep that makes sense... I'll run a couple extra battens underneath to strengthen up the verge. I'm going to embed some metal in the walls and fashion up some steel bars to hold down every other slate too, which should help with edge wind- lift. I didn't get slate and half's in my order unfortunately.