Roofing problem.

johney

Hello folks,

this is probably for the more experienced people here as it's an unusual issue.

took over the renovation in my spare time of an old cottage and am left with a little problem.
The front wall did not run parallel with the back wall. There was a difference of 150mm in the gable widths.
I got around this issue by placing a new wall plate on top of the joists over back wall and squaring up the back wall plate to keep the roof square. However, now there will be a difference in the soffit width if I keep the facia square with roof. Or I can keep the facia parallel with the back wall but will have to cut the first row of slates a different length which will look terrible.

Any ideas.

Thanks in advance.

Calahonda52

keep the slates the same

Roger Mellie Man on the Telly

You'll read a tapering fascia more than cut slates from eye level.

johney

thanks lads,

the issue is there is a 5 inch difference which is quite a bit in the soffit.. Was thinking of maybe leaving 3 inches difference in soffit and 2 inches in slates? 2 inches on first row over whole length of house would probably not be noticed, at least not by a lay person.

Thanks a lot

Thespoofer

Are you going to externally insulate/render by any chance?
I was in a similar situation couple of years back where one wall was leaning quite badly so I rasped the back of each insulation board before fixing to get it level ( from top to bottom). Maybe you can do the same from side to side.

Will be a bit of work but worth it, also you may need to do only the one wall.

I ended up doing the whole exterior!

Le shovelle

Your thinking along the right lines but 3 inches is still a lot in the soffit.
1 1/2" in the soffit wouldn't be noticed.
Spread the remaining difference out over approx 10 row of slates. Dont alter the bottom row, start on the 2nd or 3rd row up.
Also make sure to work out your spacing from the ridge down as it should be square to the rafters.
Old houses sometimes need a little humoring :-)

johney

thanks Le Shovelle,

it seams like you know what you are talking about. Does that mean that after a couple of rows up, I will start to increase the slate sizes tapering gradually by a mm or 2(depending) and I will also have a gradual taperig increase of distance between battens?

thanks again for the help

Le shovelle

I've been thinking about this earlier and I think you need to move the wall plate out until it runs parallel with the wall meaning your roof will be wider at one side.
This will mean measuring every rafter individually from the birds mouth to the plumb cut at the ridge but keeping the rafter tails or overhangs the same.
This ensures your fascia board will be level and soffit will have the same overhang.
Roll out your membrane and fix first two battons as normal.
Work out the spacing for rest and pull a chalk line on the membrane every time.
Try and lose the difference in spacing before the final two battons at the ridge.
I hope this makes sense

johney

thanks again Le Shovelle,

the roof is already built and it's ready to felt and slate. Haven't put on any facia yet as this is the stumbling block.The front of house is perfect. The difference is at the back and is not really seen.

Thanks again.