Roof for a large shed

[Adrian]

We've got a large studio/shed in the back garden - roughly 6x10m. The existing roof is good old asbestos/cement sheeting, and there's at least one bit that's broken away on one edge - inside's got some localised black furry mank in that bit.

The inside of the roof is probably just hardboard attached to the timber, and there's a couple of thoroughly manky not-very-see-through corrugated clear plastic rooflights.

So, we need to do something...

I know that the "Big A" in the old roofboards is likely to get everybody's invoices perking up way in excess of the actual risk, but getting shot shouldn't be a problem, should it?

What would you suggest to replace it with? Doesn't need to be tile or slate, corrugated sheeting of some kind's just fine, but what? We're going to keep rooflights, but probably a bit more refined than just clear bits of roof.

[Tim Watts]

On Tuesday 06 August 2013 11:12 Adrian wrote in uk.d-i-y:

No.

I took some asbestos down the dump yesterday. Admittedly a small few broken bits (about 1.5 ft sq) but it was easy.

Had to double bag it (I wetted it first). Bag 1, tape, bag 2, tape.

Rang the council and found the nearest tip (not my local) that took it - and I did not have to ring ahead. Just saw the bloke, gave it to him, no hassle.

Some councils want notification of a drop first. Best to ring ahead.

Anyway, don't break it - hose it down, both sides, disassemble it with reasonable care, bag and double bag in manageable sizes. Take to dump.

Someone mentioned Onduline earlier - and I must admit I like the look of their products.

[Piers]

I have a bunch of onduline I need to get around to fitting onto a large shed at some point. Looks like good stuff.

But, it's not cheap, and if it's a relatively shallow pitch you need quite a lot of support for it.

[Andrew Mawson]

A friend roofed his field shelter in Onduline, and over winter it collapsed and fell to bits. Quite possibly his supports were not close enough but it failed totally and utterly. It also only comes in 6 foot lengths which is a pain.

I would recommend that the o/p uses a sandwich box profile sheeting system that give good insulation as well as water tightness. I put some 100mm thick sandwich box profile on my woodwork shed, it went up quickly and has proved a total success.

AWEM

[Tim Watts]

On Tuesday 06 August 2013 13:40 Andrew Mawson wrote in uk.d-i-y:

oh...

What's "sandwich box" profile sheeting? Is that like conservatory plastic roof stuff?

[Adrian]

I'm glad you asked that, 'cos google didn't help me much...

[Andrew Gabriel]

I was looking for insulated roofing on ebay recently, and there are several people selling the corrugated interlocking panels which are used to build refrigerated warehouses with very thick insulation. These panels are large and cheap per sq metre, but in my case, slope the wrong way (would need to cut across the panels multiple times).

[Tim Lamb]

In message , Andrew Gabriel writes

I used an Evolution *demolition* saw to cut double skinned box section roofing with a 75mm foam fill. B' noisy and you have to watch flying swarf but did the job.

I haven't yet tried a diagonal cut for hipped roofing....

>

[PeterC]

My shed has about 7 - 8 deg. slope so I used a full deck of 9mm WPB ply and

4 joist for 3m. The 60-yo shed next to it has no deck and 1 joist for the same figures. Asbestos cement was bloody good.

[PeterC]

I'm interested, as I have a shed to re-roof and Onduline would be v. difficult to fit on brick walls, low pitch and 1 joist in 3m.

[Tim Lamb]

Google Steadmans, Carlisle. I wouldn't call it cheap though!

One issue which I haven't resolved is the foam exposed at the eaves. The under sheet and foam fill is trimmed back by 100mm or so to allow rainwater to drip clear. Pre-formed foam filler strips are available to seal at the ridge.

[Tim Watts]

On Tuesday 06 August 2013 16:35 Tim Lamb wrote in uk.d-i-y:

OK - That is a bit "industrial" for my shed!

[harryagain]

You can get an identical appearing product which has non asbestos fibres in it. Or You can get box profile (galv and plastic coated steel sheet). Much lighter and easier to handle. Full length pieces, fewer joints. You do the measurements and they cut it off the roll for you and all the bits and pieces. Fixings crests etc. Many colours and qualities. They also do roof window stuff to the same profile. Most of them can give you an instruction book on fitting measuring up etc. Easy two man job.

[PeterC]

Yes, but one of the products looks like a direct replacement - I bet the builders 60 years ago didn't faf around as much as the info. suggests.

[Tim Lamb]

While Steadmans make the rolled steel stuff, I think they buy in the fibre sheet from

[PeterC]

Yes, it says that on the page - I suppose that fibre sheet is quite difficult to make to a satisfactory standard. The steel just needs the sheet material and big machines.

[Chris Bartram]

My local council supply bags on application. If you use those you can just take them to the tip IIRC.