This flaming garage pent roof is giving me a headache. It's a 6m deep,
5m wide building.

I have found that I can't use 3" (sinusoidal) corrugated iron, 'cos the
height peak to peak of the stuff is only 19mm, and I've a 6m run, and it
is likely (!) to leak, 'cos it needs a minimum 10° slope, and I've only
got ~4.4. So it's got to be 34/1000 box profile, which is said to be OK
down to 4°.

There are still disadvantages from my perspective, but I think I can
live with them.

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!

So what's the done thig with this stuff? I'm getting pretty thirsty I
can tell you.

In message , Chris Bacon
writes
This flaming garage pent roof is giving me a headache. It's a 6m deep,
5m wide building.

I have found that I can't use 3" (sinusoidal) corrugated iron, 'cos the
height peak to peak of the stuff is only 19mm, and I've a 6m run, and
it is likely (!) to leak, 'cos it needs a minimum 10° slope, and I've
only got ~4.4. So it's got to be 34/1000 box profile, which is said to
be OK down to 4°.

There are still disadvantages from my perspective, but I think I can
live with them.

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!

So what's the done thig with this stuff? I'm getting pretty thirsty I
can tell you.

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.

--
Tim Lamb

On 12/05/2021 18:57, Chris Bacon wrote:
This flaming garage pent roof is giving me a headache. It's a 6m deep,
5m wide building.

I have found that I can't use 3" (sinusoidal) corrugated iron, 'cos the
height peak to peak of the stuff is only 19mm, and I've a 6m run, and it
is likely (!) to leak, 'cos it needs a minimum 10° slope, and I've only
got ~4.4. So it's got to be 34/1000 box profile, which is said to be OK
down to 4°.

There are still disadvantages from my perspective, but I think I can
live with them.

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.

"Chris Bacon" wrote in message
...
This flaming garage pent roof is giving me a headache. It's a 6m deep, 5m
wide building.

I have found that I can't use 3" (sinusoidal) corrugated iron, 'cos the
height peak to peak of the stuff is only 19mm, and I've a 6m run, and it
is likely (!) to leak, 'cos it needs a minimum 10° slope, and I've only
got ~4.4. So it's got to be 34/1000 box profile, which is said to be OK
down to 4°.

There are still disadvantages from my perspective, but I think I can live
with them.

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!

So what's the done thig with this stuff?

With mine there is a tool that turns up the end so it forms
a dam and the flashing down the inside of the barge board
across the 5' wide front goes down into that. But my decking
has very narrow upstanding bits, it isnt so easy with the
decking with wider verticals, but still possible.


I'm getting pretty thirsty I
can tell you.

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.

On 13/05/2021 16:47, Chris Bacon wrote:
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..

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

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

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.

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.

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°).

"Chris Bacon" wrote in message
...
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

That one shows the dam done by bending up
the end of the high side I was talking about.

Works very well for me, no water gets
blown back over the dam in a big storm.

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.

On Fri, 14 May 2021 06:58:17 +1000, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

FLUSH the trolling senile pest's latest troll**** unread

--
Norman Wells addressing trolling senile Rodent:
"Ah, the voice of scum speaks."
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