Joining flat roof to existing pitched bungalow roof

[Mark Williams]

I am extending a bungalow where the existing roof is pitched in each direction. The extension roof will be flat GRP due to cost and my relevant experience. The plans are for the extension to extend the full length of the side of the house. Being a bungalow, my new joists will cut into the roof space to meet with the plate on the internal wall. At present the Sofit sits about 250mm below the plate. My issue is that if I just cut into the roof with the new flat roof I will cut into the hip and beyond the existing front facing pitch. I have seen examples of EDPM where the edge has sloped to follow the the hip but I am not sure how this would look at the front of the house. If I were to do this, then I suppose my options at the rear are to run level and cut into the hip with a view that it is at the rear and will not be seen so much or follow the hip as per the front and just gutter each side? I have considered a partial pitch on the front but I am looking to keep things simple as, bar some work with GRP I am not a roofer. I am also looking for a reasonably swift option as with winter coming I want to keep the time between cutting into the existing roof and finishing the GRP on the extension to a minimum.

Any thoughts really appreciated.

 

[noseall]

Joining a flatty onto a pitched involves chopping all the existing roof stuff that exists below the level of the wall plate. It is largely cosmetic in so far as the "A" framing is concerned in any case.
You then build this junction with ply layboards that extend up the roof far enough in order to sufficiently weather. You then fix an angle fillet (which the flat roof material must cover) onto the play layboard and this acts as your first tile kicker.

The images below show a greatly reduced fascia detail. This is a problematic issue with most modern flatties due to the latest warm roof spec'.

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• noseall
• 3 Nov 2014
• 2

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• noseall
• 5 Nov 2014
• 1

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• noseall
• 5 Nov 2014
• 1