living, or green, roof

[Frank9755]

Anyone know about these, where you have a flat roof and have sedum, moss or grass growing on it? Helps to prevent storm run off and improve insulation of building + good for bees, insects, etc.

We're thinking of having an extension done and it would be good to include this if not too hard.

[Brucey]

building needs to be stronger than normal by ~50kg/sqm to ~250kg/sqm, depending on the approach used. On top of that you have to allow for the possible extra weight of snow, lots of rainwater sitting up there, folk wandering around etc as normal. So a system that is usually about 45kg/sqm (about as light as such roofs get) needs to be supported by a structure that is strong enough to take about three times that.

cheers

[Aunt Maud]

Yes, I've put two on so far.

One on my workshop which has a 6" growing medium for meadow flowers and one on mums extension which has a 4" growing medium for sedum and drought resistant flowers.

I used a Firestone butyl rubber pond liner both times for the waterproofing. It's fast and easy to lay and has a 30 year guarantee and factory sealed seams, just roll it out on top of your insulation and you're waterproof in 30 minutes. I have felt underlay on top and below for added protection.

The gutter detail at the front needs careful detailing. I used a hidden gutter with Lindab steel guttering both times. A quality gutter and easily fabricated with a holes and tin snips. I can't stress how important it is to get this right first time, so you need to over engineer it to make sure it's done properly.

As Brucey said, you'll need to beef up the roof with a bit of steel and 2"x8" joists.