Garage Roof Re-Covering

[M.J.S]

Howdy all,

A while back I asked about fixing a few leaks in the garage roof, and the general feedback was think about replacing it.

So I've thought about it and done some research and bitumen corrugated sheets seem to be the best way to go. Now can I just lay these over my existing corrugated cement (and possibly asbestos) sheets? Or do I need to remove the original roofing material?

I guess the 'proper job' would be to remove the old ones, but they would provide support and structure to the new sheets if they were to stay.

Anyone have any suggestions?

Thanks

[Meeja]

I am planning to do the same to my garage roof (13m x 9m - so quite a large area)

I plan to remove all of the original cement sheets (taking precautions in case of asbestos) and then cover the existing roof joist timbers with either 11mm or 18mm OSB ply (the kind of stuff they use for boarding up buildings), then fit the bitumen sheets over the top.

The ply will give more stability to the bitumen sheets, will probably help with soundproofing when working in the garage when it is raining hard, and won't cost the earth to fit.

[M.J.S]

Yeah I think thats the best plan, just seeing if its possible to leave the old ones there as getting rid of them will be a pain, another trip to the local tip, which with great customer service in mind closes at 6pm on a week day.

[Meeja]

Depends on your local council I suppose... worth asking them the question?

A friend of mine lives in adjacent local authority area to me, who periodically run a scheme whereby they will collect asbestos sheets from you, providing you prepare them properly (watered down and double poly-bagged)

He is letting me know next time they run the scheme, and I'm transporting my lot over to his house!

[Simpo Two]

How much would zinc be, a la Grand Designs?

[M.J.S]

Simpo Two said:

How much would zinc be, a la Grand Designs?

I've no idea! Not even though about it... I'm guessing though more than corrugated bitumen

[mrmaggit]

If you go with steel corrugated roofs, your local bird population will sound like they're just bought-out the cobblers of hob-nail boots.

Take toe current sheets off, then replace with whatever you decide.

[Mr GrimNasty]

The chances of the corrugations matching well enough for a direct overlay are zilch.
That bitumen stuff is a waste of time.
Strip the lot and do a proper flat roof with epdm or felt.

[Skyedriver]

Most tips won't take asbestos and if they do they charge a lot.
Best roofing material is glass fibre I reckon, long guarentee and if there's a problem it can easily be repaired
Price: Double garage (tandem), strip old straw boards, re align joists, new boarding, new fascias, glass roof £2650