On 12/05/2021 23:18, Steve Walker wrote:
On 12/05/2021 18:57, Chris Bacon wrote:
One thing I can't have, though, is the 5m wide front of the thing
looking like castle rampartd in miniature, so it needs some sort of
flashing to get over that.

What's used for this? Barge boards, yes, for the sides, which are like
sheet metal equal angle, but what about the ends? Surely if I just use
barge board, the 90° angle will be wrong, and it will allow water to
blow up the tiny slope, and run back under the roof sheets, which is
not what is wanted!

90° barge flashing should be fine. It flexes a bit, so should fit over
the high end with no problem - with sealant at the join or closed cell
foam strips pushed in, to stop rain blowing up and over the end behind
the flashing.

At the low end, sit it on the roof sheets, but set it back an inch - so
that the ends of the sheets are an inch back from the vertical of the
flashing and can drain to the gutter below, but are hidden.

In my case, I haven't done that, but with a low angle, I siliconed and
rivetted 10mm aluminium angle along the end of the bottom of the sheets,
as otherwise I found that water stuck, turned under and was blown along
the underside of the roof sheets, causing damp.

What angle fall did you have? I'm struggling to get more than 4.4°,
unless I go apex roof..

I see about the bargeflashing. I want a non-crenellated front, so that
sounds good.

In other words I don't want the front to look like this:

https://vsfgaragerepairsuk.com/asset...0-968x1291.jpg

But instead like this:

http://www.concretegaragecentre.co.u...6/03/Roof4.jpg


Most barge flashings seem to have 200mm of cover. That only allows 15mm
of fall between the edge of the bargeboard and the end of the box
section sheet.

What do you think about this technique:

https://www.youtube.com/watch?v=ixTvyav6NHc


I may have to just say "Buggrit" and go for an apex construction, as it
is, which would allow me to increase he eaves height, which is what I
want, then I wouldn't need barge flashings at the 6m sides, as I could
stand that, but not face on from the back kitchen window.

I'm on the horns of a dilemma. This building is a sectional garage
that's now in my back garden and will be made into a workshop.