On 10/05/2021 11:27, cf-leeds wrote:
I need to replace a very leaky old garage roof, which is currently in corrugated asbestos sheets (I think they're asbestos anyway). I'm aware of the disposal process for old asbestos roof and I have details of the local council disposal process for asbestos - I'm ok with all that.

My question is what's the best replacement for the roof.

It's a flat sloping roof with a single gutter across the back end of the garage - It's a prefab garage. (not a pitch roof).

I thought I'd just look online for some galvanised corrugated metal sheets, around the same dimensions at the old asbestos, but I find there are many products out there, including corrugated bitumen sheets.

Can anyone offer some advice on a good option here.

My main criteria are, easy to install, good-value, long lasting in terms of no discolouring, if they happen to be dark great for example. Is there anything that you'd definitely avoid ?

Any tips welcome.

Thanks in advance.

The problem with Onduline or Wickes own brand corrugated bitumen is that
it is only rated for 10 years life, especially if the slope is shallow
or the purlin spacing large. I need to replace my shed's roof this year,
admittedly that lasted 25 years, but we rent a stables where it has
failed badly at 10 years. Basically, it sags and then tears. It will
certainly last longer if you board underneath it with sterling board. I
have not quite decided whether to do that with mine, or whether to
convert to plastic coated steel, or perhaps to corrugated fibreglass
(which is a bit more expensive).

It gets slightly lighter in colour over time, not enough to matter IMHO.

Metal sheet comes in a range of thicknesses and geometries. The thinnest
(eBay) lasts pretty well, it is light and pretty easy to cut and fix. If
in a windy area you need to make sure the edges are well fixed down.