Adhearing to neighbours pitched roof

[duchard]

I'm trying to kick start the planning of my new rear extension off (single storey) and wondered if my roof needed to be of the same pitch as my neighbours.?

They have recently completed their extension and it looks like the roof pitch is pretty low at around 22 deg. I suspect at this angle the roof build would need a better spec to comply with building regs. Would this cost considerably more that a normal 30/35 deg pitched roof?

I was hoping to use clay tiles to keep in match with my existing roof but not sure if the spec of them would allow for such low pitch.
They are using slate tiles which look good but I'm kinda under a tight budget with the project. I hope to go out to a depth of 12ft through planning permission which would be about half a metre over my neighbours extension.

Our houses are joined as a semis so not much room between them.

Anyone got any advice / help on this one?

 

[inspector01]

Most roof tiles are suitable down to 17 degrees with a suitable overlap. Check the supplier of you existing tiles to be sure, alternatively post a pic here and I will see if I can help identify them.

 

[^woody^]

You can use a tile at a pitch lower than its recommended one, if you form a watertight boarded and felted layer below the tiles.

Effectively you build a flat roof (albeit on a slope) and then tile on top of this.

You need to watch the eaves detail though, or you end up with a massively deep fascia