Flat roof levelling and using EPS/CNC

[Ronnie Chowdhury]

Hi all

I'm trying to figure out how to build up my flat roof with the correct layers. The surface is concrete beam and block, with a parapet, 400mm high 300mm wide along the edge. The proposed roof design is a taper for the rain water to the back of the house. The total size is 125sqm.

I also own a (hobby) CNC machine (1.2m*1.2m) which is relevant below.

1. Tapered insulation from celotex/kingspan etc is expensive. Can I buy flat sheets and cnc them to the design required? I know you can cut them to fit, but the foil backing is not removed then. With the tapering the foil would be removed as the pitch is cut out?

2. An alternative I thought was to use EPS100 foam (thicker layer needed i know), but this is easy to cut to shape.

For reference: Below the EPS would be the VCL and above the EPS I'd put OSB and then the final roof layer - EPDM.

Does anyone see any problems with this idea?

 

[chappers]

build the fall with tapered furring pieces made from timber

 

[Elastomeric]

As above. Using EPDM means you will need firings/Osb/vcl/insulation/osb/epdm.

 

[Elastomeric]

As above. Using EPDM means you will need firings/Osb/vcl/insulation/osb/epdm.