Diy help, corrugated sheet joining on hips

Evening all,

I’ve been tasked with building a wrap around porch in what was going to be my man cave, for the wife’s childminding business 😠. I’ve built a frame around, inuding penning the little folk in, but I’m struggling with how I make the roof water tight. On one end, I have a flared end with 3 hips, and with corrugated sheets I can’t figure out how to finish the hips to make them watertight.

Do I use a mixture of butyl flashing tape, and say a shallow ride cap, or look at rafter capping bars (designed for flat poly sheets or other glazing)?

I know one answer is to use flat poly sheets, but my orders are to use corrugated, so I’m stuck…

Picture for an idea..

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A little upgrade for the #cabin #logcabin, off with the old lean to and on with a new full enclosed canopy (in progress) and fence all round. Big thanks once again to a brilliant mate @adyhdr for giving up his time again to help out, always good bantz on the job! #suimansion

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Thank you
Sui.

I’m pretty sure that basketball hoop is way below the industry standard height.

On a more serious note, corrugated sheets always look nasty after a year or two. And they look shit anyway.

Maybe a canvas type covering? That would fit the aesthetic of the shed more, I would have thought.

@mattyfez, the wife has spoken, she wants lots of light coming through. Perversely it was the honeycomb poly sheets was against due to the dirt getting in between the layers!

This is one of those, must find a solution irrespective of the other options times.. 🙄

Metal flashing surely.

You’ll be able to get hip lengths for this type of application, having said that the pitch looks very low so you may be better off with some flashband

If you decked and felted the hipped corner bit and used corrugated sheets for the rest that would still give loads of light to the windows- and having a bit of shade available is likely to be useful depending on the orientation- reduce sun-stroke risk etc.

How about some old school lead flashing? Maleable to shape, up out of kiddy reach and aesthetically pleasing to SWMBO?

Old lead roofer here 🙂 Trouble is with that suggestion that unless you put a wood core roll up the hips to hold the lead in place it wouldn’t sit very naturally on corrugated sheets. Additionally it’s a very low pitch, which will have a lesser angle on the hips. This is unlikely to cause problems for general rainfall, but with any wind it’s likely to blow under any detail of that nature. I would be looking to use something that bonds to the sheets, like flashband, although this is very ugly. A hybrid approach would be to source the roll out under tray from a dry ridge system (roofing merchants) which has tacky rubber edges and will adhere to the sheets, but a fabric centre so allows ventilation, and then try to source an industrial dry hip section, these are usually composite and are approx 200mm wide and can be available in 3-4m lengths. They are quite discrete and would mean that you could do the length of a hip in one section, negating laps.

Palmer77 sounds like he knows what he’s talking about 😉 but an alternative might be to try a Sarna flashing? Maybe with a drip tray under the length of the hip because it’ll be quite tough to guarantee water tightened without going completely overboard with flashing.
Whatever you do is going to be difficult especially as your pitch is so low.

Heh heh

Sarna

The devils choice 😉

I think the idea of felted hips sounds the tidy way. Say 300 mm wide (could go wider) to 150 mm each side then butt the sheets up to the small felted roof.

thanks all, yes pitch is very shallow, i think it’s around 5degrees.

@palmer77 thanks for the info, i had thought about trying out a dry ridge system, but use a valley tray underneath, i may even have some dry ridge stuff left over form my house roof somewhere.

do you think sandwhiching two of these would work,??

https://www.roofingsuperstore.co.uk/product/redland-rapid-hip-support-tray-12m-pack-of-10.html

When i say water tight, i really just means it’s got to just not leak like a sieve in moderate rainfull – it’s all open, so any gales will just run through the sides!

I’ll never get away with a felted hip!!

actualyl edit – i think i’ve just got what you mean… that may well work.

Hi, I was thinking that you could use something like this https://www.roofingsuperstore.co.uk/product/onduline-verge-1100mm-width-brown.html on top of the roll out part of this https://www.roofingsuperstore.co.uk/product/manthorpe-roll-out-dry-ridge-system-6m-pack-black.html on top of the corrugated sheets.

cheers palmer – do you think i’d then need to have a batten to separate the 2 sheets, so that the roll can be nailed down, or do you not need to do that?

i had 2 of those kits left over but binned them a while back (roofers fitted them)..

Yeah a batten wouldn’t hurt, maybe a noggin along the hip rafter, or out the batten on edge (so there’s space to lap the sheets onto the hip) if you want to fix the sheets there to prevent windlift