Corrugated shed roof replacement – what's best?

I’m having the sloping asbestos cement roof taken off the outbuilding / shed at the new residence to appease my fiance, but obviouslly I’ll require a replacement roof covering to keep the fleet dry and happy.

At present I have about 8 9 foot by 2.6 panels

It would be nice if it was a bit lighter inside but still low key from the exterior. Would doing the whole thing in the transparent stuff be weird? How easy is it for the scrotes to break?

This I likely to be a semi – temporary arrangement until the new garage gets built (18months -2 years)

Coroline/Onduline bitumastic sheets can be got for c.£10 each. You can get matching clear plastic profiles too to make a skylight panel (about £20-30 IIRC).

Cover width is 855mm (allowing for the correct overlap) and they are 2m long. The can be cut easily by hand using a jack saw. You can get matching ridge pieces as well. And dont forget to allow for capped roofing nails.

http://www.arielplastics.com/
http://www.onduline.co.uk/

Available from your nearest builders merchant, and also eBay.

Easy to install. Lightweight. Ive used it on my garage, and two woodstores.

if your asbestos is still watertight , whole and undamaged – and its a temporary arrangement

why change?

asbestos is only dangerous once you start fannying around with it.

undisturbed it will do you no harm

what ever you do stick on the roof i suggest insulating the underside with airgap + kingspan or similar – stops condenation forming 😀

I have that stuff stoner has on one garage and plastic correguated on the other.

dont really notice much difference between the 2 if im honest.

my asbestos roof on the othershed is gubbed , gone porous – so its the wood shed now – till i tear it down and make my kitchen bigger 😀

if your asbestos is still watertight , whole and undamaged – and its a temporary arrangement

why change?

I have been instructed to do so by her indoors. I have got a reasonable quote to get it stripped and disposed of (our council won’t take it, and anyway it’s too big to go in the car)

what ever you do stick on the roof i suggest insulating the underside with airgap + kingspan or similar – stops condensation forming

that’s the kind of info I’m looking for 🙂

The current sheets are 2.7m long – so in some materials I could just do a single span – however the onduline only comes in 2m sheets. This would work if I wanted to put in a row of rooflights, but will mean a lot more joins. Is that something I’ll regret in future?

You can cut the 2m sheets in half. Rather depends where your purlins are.

Joints arent really a problem. A row of rooflights would look quite cool. The plastic sheets need pilot holes though.

Is that something I’ll regret in future?

Not as much as disobeying her indoors, I’d wager.

Stoner has it.

depends where your purlins are.

Yeah I realise this might be an issue – I’m away at the moment so everything is based on a few fag-packet-esque scribbles – but I’ll need all the materials in place the day after I get back.

I’m also trying to hire a MEWP to get the asbestos guttering down off the back of the house, rpelace that, inspect the roof and prep and paint the bargeboards. Looks like a busy weekend.

If the rooflights are small shouldn’t be too much of an issue, but be aware of differential thermal expansion. Polycarb expands LOTS! seen roofs where the rooflights have buckled the fixings ripped through etc. If your going to use them ignore anything you read, they will expand and you will need to allow for this when fitting.

As for security they are all as bad as each other.

I am assuming you have timber purlins? just be aware that moisture can be an issue as the timber absorbs moisture and can release it where the sheets join, plastics should be ok on this front.

Be wary of spacing on your purlins when using onduline, it has a nasty habit of sagging if not supported enough!

onduline+1

I put the Wickes version of it on my shed after the felt started leaking. That was about 10 years ago and it’s still going strong. Easy to work with, cut with a normal saw etc. Wickes have a little info sheet on how to fit it with batten spacing requirements etc.

http://www.wickes.co.uk/bitumen-corrugated-sheet-950mmx2m-black/invt/240039/

Wickes DIY guide http://www.wickes.co.uk/content/ebiz/wickes/resources/images/gil/44.pdf

Onduline is good stuff. Don’t be tempted by the mini version though, the fixings aren’t as good (it’s a nail with no cap) and in my experience are prone to leaking (potentially down to my ham fisted installation!)

12mm ply it first, will solve any spacing issues and add a lot more security if that’s what you’re after.

wrightyson +1

Onduline on my shed roofs on the allotments has been fine until last year. Combination of heat and water with a shallow fall on two of the flat roofs has led to extreme bowing. Have placed extra purlins at 12″ intervals (they were 2ft and this was fine for 5 years), however the roof is still bowing and i need to replace the lot. Thankfully its really easy to cut and fit!

Just read your last post, 12mm ply sounds like a great idea for a shallow fall roof. 🙂

2ft spacing (610mm) is much wider than the recommended max of 450mm for a shallow slope roof to be fair 🙂

True! but I inherited the sheds to be fair… and they are of typical allotment standard!