Extension pitched vs flat roof

[Ash101]

Hi all,

We are doing a 6m deep rear extension and could really do with your thoughts _/\_

Our adjacent (party wall) neighbour currently has a 3m extension with pitched roof.

We are looking to match the neighbours pitched roof (with pitched internal ceiling below) and then transition to flat roof (with flat ceiling below) for the remaining 3m. The pitched part of the roof is to have a large skylight/velux to let light back into the original house. Now I searched everywhere to see what this may look like and all i could find are either pitched ceilings or flat then leading to pitched, not pitched then flat.

Would be very interested in hearing peoples thoughts and ideas and whether there’s a reason for not being able to find something similar on the internet.

Thanks

 

[Bonni]

A golden rule in life, flat roofs leak.

If you did the flat roof in that rubber stuff, there's screws and fittings to fix it down so far up the pitched roof under the lower course of tiles. I'm a builder and I would never have render, box gutters, or a flat roof.

 

[freddiemercurystwin]

Nonsense you dinosaur.

 

[johnny2007]

A golden rule in life, flat roofs leak.

In the old days, maybe.
A flat roof built properly doesn't leak and lasts a long time.
Fibreglass roofs, left untouched would probably last as long as tiled roof.
Op, around my area I have seen plenty of deep extensions similar to what you describe.
That's because the pitch for tiles is not achievable all the way as there are upstairs windows.
Have you spoken to a good roofing company, not the millions of riff raffs pretending to be roofers?

 

[Koolpc]

A flat roof done properly will last decades....

 

[Ash101]

Thanks all, I think we’ll go with a pitched roof, it will end up between 15 and 20 degrees.
We will go for a sloping/vaulted ceiling beneath (to get the feeling of headroom/space) which will then transition to flat - hoping this looks nice from inside as I’ve not seen any photos of anything similar in all my searches on the internet!

 

[robinbanks]

Our adjacent (party wall) neighbour currently has a 3m extension with pitched roof.

as in pitched up to the boundary line so the boundary is the ridge?
And your extension is wider than theirs so when you copy their pitch your angled part finishes before it reaches the wall?

There are many examples of pitched roofs that dump onto flat roofs; any flat roof extension could end up thus