My garage roof is totally knackered, the whole lot needs replacing including the joists.

The various companies are reluctant to provide an indicative cost without coming round to provide an estimate, at the moment I’m just looking for an idea of price per sq. metre for the various coverings.

As anyone looked into this and got an idea, of say price per sq metre for the different types? Total roof is 6.5×3.0 metres.

My garden slopes steeply above the garage and anything would be better than the crappy old asbestos sheeting! I really like the idea of the lightweight sedum roofs, apparently the cost is comparative to a good 3 ply felt roof but the green roofing websites are biased! I would be looking at the pre-planted sedum mat type roof.

Plus point of the Sedum roof is it would make the garage a bit of a feature whereas with a boring standard roof it would still be a bit of an eyesore!

Watching with interest. I can only patch my flat roof so many times…

Well from three companies I have one ‘guide estimate’ of £3250 for a GRP roof, including disposal of the old roof/asbestos. However its been 24hrs and they haven’t said when they can come round and do a quote yet…

(that company don’t do felt or green…I know felt would be cheaper than GRP)

How handy are you at DIY? When I was a window fabricator/fitter a few years back we did a couple of GRP roofs on the odd porch and they’re really simple to do. You can buy all the gear from CFS and they give pretty good guides on the website how to do the job!

We’ve laid a sedum roof to part of our new house. It’s lovely, but it is an extra cost – you need a completely waterproof single ply or grip roof to lay it on. You’re also adding a load of weight so you need to ensure the structure is strong enough.

Very easy to self lay though – price up the sedum element from somewhere like http://www.sedumgreenroof.co.uk (they’re not necessarily the cheapest)

As above, you still need a waterproof roof for green so it is likely to be more expensive. For a garage you might get away with a more basic waterproofing layer then rely on the green element to mechanically protect it. Not sure if anyone is doing that commercially but it’d be an easy and interesting DIY project.

GRP and EPDM are both relatively easy to DIY, materials are readily available as are on line guides.

Colleague of mine replaced a section of his roof with the EPDM rubber stuff & reckoned it was really easy to do. Worst bit was getting the large sheets of board up onto the roof that the EPDM sits on.

I looked into it, for re-doing our garage roof & loads of the websites have calculators to work out the material cost. You then need to add on the cost of the boards etc.

I am capable of doing it myself but logistically I am single-handed and as it includes putting in new joists it would take me ages whilst half the garage is in the dining room/garden!

I think this is one job where its best just to cough up and get it done in a day.

Well, plans moved away from Sedum to a basic roof, a few not so tempting quotes later (3250 for GRP and a light dome, 3150 for felt and a dome, 2000 for felt and no dome but I’ve got to dispose of the asbestos).

Now been referred to a guy who specialises in the metal profiled roofs, I was considering them as DIY before. Profiled metal outside, insulation, and then a bright white profiled metal inside.

And the price looks to be the lowest so far, and that includes certificated removal of the asbestos. The sheets need to run in one length, so its probably 3 or 4 continuous lengths of 6.5m. My dilemma now is it should be brighter as its white inside, but do I forgo some insulation and get a full length opaque panel to flood the garage with light? It’ll be double skinned but presumably a weak point for intruders, possibly a bit of a condensation collector as well? No plans to heat the garage…

Colleague of mine replaced a section of his roof with the EPDM rubber stuff & reckoned it was really easy to do. Worst bit was getting the large sheets of board up onto the roof that the EPDM sits on.

I did this for the whole of my garage roof. 6m x 3m garage, cost about £450 for the EPDM/glue/finishings and about £550 for the wood required to build a whole new roof frame on top of the garage walls. Took 2 days all in, and it was super easy.