New Garage Roof

BigHead26

Hi all,

I’ve got a garage with potential asbestos cement roof ( apparently built 20 years) that is cracking and leaking all over and needs replacing. As it’s my first garage I’d like some advice please on a replacement roof. It is a pitched roof with steel supports and have been given quotes for fibreglass and metal. What is the best material to use on this type of roof? I’ve read metal causes lots of condensation and fibreglass makes really loud cracking noises so am unsure of the best material.

Thanks for any help anyone can offer

Furts

Subject to any Planning implications, I would do neither of your scenarios. I would put on a proper roof with tiles and underlay. An easy, quick way where I am located is to get some trussed rafters made. They do the design, and they deliver them to the door. But a competent builder/carpenter could do a cut timber roof instead.

I cannot picture your pitched roof with steel supports, but you may be able to insert timbers, then underlay and tile battens, and get this structure to receive roof tiles.

Since a garage is not a Buildings Regulations matter there is no need to concern a Structural Engineer and design. But you can if you wish.

Crag30

I had my asbestos roof replaced with steel last year. The steel seems to have a coating on the underside to stop the condensation. Well I had no condensation over the winter even with fridge freezers in there.
Have found leaves etc don't hang onto the steel well, as a light breeze blows them off. It's considerably warmer in the garage than with the asbestos in this heat.

I'm happy with the result.

Gloomendoom

I have a porch canopy thing (open three sides) with translucent corrugated fibreglass panels. It lets light through which is good. I've never heard it making noises but it does get condensation on the underside in winter that drips.

I have corrugated steel roofing on part of the house. It's quiet but can't comment on condensation as the underside has an air gap plus 12" of insulation. The room underneath is decidedly cool even during the recent warm spell.

As a quick temporary measure to cure a leaking felt roof on my garage, I fitted some cheapish (Screwfix) white low profile corrugated plastic sheets. They let light through which is useful, but they are noisy in the sun and get condensation on the underside despite having a minimum 4" ventilation gap on three sides. Been on there 10 years now with no leaks.

The intention is to replace the current garage roofing with corrugated steel.