Patio on a flat roof?

[Al Reynolds]

Afternoon uk.d-i-y people,

While thinking idly about extending my house, I happened on the idea of having a patio on the flat roof of my extension. Only problem is, all the flat roofs I have ever seen in the UK have that felt and membrane option where you either (a) can't walk on it, or (b) wouldn't want to walk on it even if you could.

In Europe I have seen patios on roofs where they have a raised wall around the edges, slabs in the middle, and a drain out through the side, at the base of the wall. I think all of these buildings were of entirely concrete construction, so I imagine that the roof was reinforced concrete as well?

I googled a bit this morning, and found various references to GRP or glass fibre membrane roofing. One example is here:

Flash-only and no HTML version).

I'm still pretty much at a loss though - what do people here think is the best way of getting a patio on a flat roof? Can anyone fill me in on the important issues to consider? I'm very much at the drawing board stage at the moment, so any advice would be helpful.

Thanks in advance, Al

[Owain]

"Al Reynolds" wrote | While thinking idly about extending my house, | I happened on the idea of having a patio on the | flat roof of my extension. ...

| I lived in a student hall of residence with concrete flat roofs. I didn't have water stains on my ceiling but some did.

Have a felt or membrane roof with upstands sufficiently closely spaced for decking to go over the top.

Two concerns may be guarding (building control) and overlooking neighbours (planning).

Owain

[Lee]

Not a helpful answer I know, but the neighbours opposite have an asphalt (over wood) roof and have a garden shed up there and regularly hold barbecues on the roof! ;) Not sure what the insurance would say about it :)

Lee

[Derek *]

Giant Firework.

DG

[Dave Plowman (News)]

I had mine constructed on the top of the addition of a Victorian semi - it was originally a pitched tiled roof.

My architect recommended a ply base with asphalt then promenade tiles on top of this - they are lightweight glass fibre reinforced concrete and very very strong.

It's been totally problem free in something like 15 years. The exposed parts of the asphalt have to be kept painted with white masonry paint to prevent the sun melting it, but this is hardly a problem.

[Mark]

Yep I also have promenade tiles on a flat roof that is sometimes used as a sitting area. They're almost 20 years old now, outlived most other felt only flat roofs that I unfortunately own.

-- mark