Slating query

[gaz116]

Hi, i wonder if i could get a bit of advice from the experts on here.

Next week i`m undertaking a Slate job. Last time i did any slating was a good few years ago and at the time i was just leraning the trade, so i`m not fully experienced in slate roofing.

Now, working the gauge out is not a problem , slate length - headlap divided by 2. My question really is can this gauge be adjusted slightly to account for the roof space, for example, say my set gauge leaves me 5 inch short at the top of the roof, can i adjust it slightly to fit. If not is the best method to "cut" down the top course of slates and top half slates?

Also, i`m not sure if the slates will be pre holed or not, if they`re not, it souldnt be a problem. But if they do come pre-holed whats the best way of coming to the correct gauge for the laths, if the normal gauge formula leaves me miles away from the drilled holes

 

[noseall]

cut down the top course.

...and don't forget the (if necessary) copper disc rivets.

 

[gaz116]

So cutting down is an acceptable method of fittting the top course then.
Makes life easier.

By all accounts the site agent on the job is a picky so and so. So i wanted to make sure the mehtods i used were correct.

Presentation wise i know i will make a very nice job, i just didn`t want something to come bite me in my arse afterwards.

 

[gaz116]

Right, i`ve just found out the slates on the job will be 500x250.
Also the required headlap is 90 mm.

Now, the thing i can`t get my head round is. The slates come pre holed at 300mm, which as far as i can fathom would give a gauge of 200mm.
but if i were to use the formula of:
Slate - headlap / 2 = gauge
I would get 205 mm. Now i know it`s only a 5mm difference and it shouldn`t cause any problems, but i`m just wondering if it will throw the slates out as i go up the roof.

 

[noseall]

you are governed by the pre-drilled holes or by gauge formula, i.e. length of tile minus lap divided by 2.

just set a few out dry to the formula and see how it goes.

 

[chappers]

don't worry about the odd 5 mm set out your battens to the holes and then cut down your eaves course to match.
As Nose says hold up a couple of courses on a dry run to get your gauge.
which ever you do so long as each batten is gauged the same it will stay the same up the roof

 

[gaz116]

Yea, that was pretty much how i was gonna tackle it.

Thanks for the advice.