Box profile roofing sheets, flashings.

In message <s7h4u3$nvk$ snipped-for-privacy@gioia.aioe.org>, Chris Bacon snipped-for-privacy@maildrop.cc writes

The suppliers of box section roofing (AS35?) will supply 1m wide expanded foam strips (ridge fillers) to go under your 90 deg. flashing strips.

Steadmans, Carlisle manufacture the stuff and their website is good for advice. Fixings can be got locally nowadays and a nearby source likely cheaper.

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:

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:

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.

Mine is 5.5°, but it is a side to side monopitch roof, rather than a front to back.

See below - if I do change to apex, I'd probably got for the foam infills rather than bending. Simpler, quicker and they'll stop water running up and over the edge, while also stopping draughts if you haven't fully boarded below. Indeed, I have used the foam infills on my (apex) shed roof.

Funnily enough, I have the same dilemma. I currently have my garage as a monopitch roof. High-side on the left and low on the right. However, I am looking at increasing the width (and length) from 11' to 13' (and 16' to 21') and can't make up my mind whether to stick with monopitch (which would drop the angle to 4.9°) or to go for a shallow apex (which would give me 9.8°).