Flat roof for new extension

misc2013

We have had to change our roof design for new extension at the last minute due to the need to move our extension - long story. It was to be mono pitch but now due to the new position in relation to the existing house, that will no longer work. We were given 2 days to decide on a new roof as builder needs to know tomorrow. We're now looking at a flat roof with that "lip" around the edge, can't remember the term. I can't help but worry about leaks but people say modern flat roofs are not flat, flat. I see so many flat roofs on modern houses and extensions and they look great.

newbie2

If your flat roof has a 15 degree pitch, it will not be deemed to be flat. Are you getting fiberglass? If so I wouldn't worry too much about leaks. Fiberglass is very good. Be aware that a flat roof may effect your home insurance costs.

misc2013

newbie2 wrote: »

If your flat roof has a 15 degree pitch, it will not be deemed to be flat. Are you getting fiberglass? If so I wouldn't worry too much about leaks. Fiberglass is very good. Be aware that a flat roof may effect your home insurance costs.

Do you mean 15deg pitch majes5it not a flat roof for the purposes of insurance?

newbie2

misc2013 wrote: »

Do you mean 15deg pitch majes5it not a flat roof for the purposes of insurance?

Yes

BryanF

Op you have given zero info above. Is it pvc, bitumen,metal, grass? As per other thread, you’ve no drawing and no details. I think you know what you need to do.

99nsr125

Don't, just don't.

You need some pitch to get the water away.
Even if it's only 5 degrees

Gumbo

99nsr125 wrote: »

Don't, just don't.

You need some pitch to get the water away.
Even if it's only 5 degrees

The term flat roof is a common term. It’s actually laid to falls.

misc2013

BryanF wrote: »

Op you have given zero info above. Is it pvc, bitumen,metal, grass? As per other thread, you’ve no drawing and no details. I think you know what you need to do.

I was simply looking for an opinion on flat roof v pitch roof. What;s been suggested is either fibre glass or trocal. I believe flat roofs are not what they used to be but still.

BryanF

misc2013 wrote: »

I was simply looking for an opinion on flat roof v pitch roof. What;s been suggested is either fibre glass or trocal. I believe flat roofs are not what they used to be but still.

What length of warranty is the builder and manufacturer offering? Nothing wrong with trocal once installed correctly. Fibre glass again comes down to the details and whether it’s u-v resistant. I’ve installed 2 ply bitumen on my flat roof.

PMBC

Anybody heard of or remember Dry-dek? On the advice of a young builder friend more than 30 years ago I specd that for a 'flat' roof extension mother's place, sealed with hot bitumen and covered with 3 layers mineral felt. It still hasn't shown a leak; but the felt was changed 15 years to ?polybutyl. At the time a lot of people were using chipboard or felt covered ditto lol.
Anyone know of an equivalent product?

Gumbo

Worth checking with your insurance company as to what their requirements for a flat roof are. My father in laws place, his insurance company insisted it’s not covered unless it was reflected by a registered contractor every 10 years.

99nsr125

Gumbo wrote: »

The term flat roof is a common term. It’s actually laid to falls.

Thanks Dad

Seeing as we are veterans of flat roofs

Don't just don't, do it the normal way and just do it right the first time

BryanF

99nsr125 wrote: »

Thanks Dad

Seeing as we are veterans of flat roofs

Don't just don't, do it the normal way and just do it right the first time

Cut this out. Your last two posts are borderline trolling.

misc2013

Looks like the choice has been taken away. It was going to have parapet but it won't work against existing roof as existing pitch is too low.

dodzy

EPDM?