Crappy roof junction detail...

[Mulberry View]

I'm fighting for my life trying to get our house water-tight, after the relationship with our Architect broke down, hemorrhaging money trying to get other Architects to fill in the blanks. I built the shell as per the plans and sadly didn't think hard enough about the next steps. This is what I have at my roofline...

 

 

That's a 200mm timber hard-edge upstand, it contains the Celotex for the warm room. This is how the Architect detailed it...

 

 

Clearly we cannot render directly onto Timber. I spotted it after the shell was built and so added an extra 50mm around the perimeter of the roof in a late-stage adhoc amendment, to enable an overhang big enough to take a secondary layer of EPS that I would add to the whole building to cover everything up and give a single layer to render onto.

 

However, I'm now second-guessing it, does the timber need ventilating? Would I be better to utilise a rain-screen system here? I'm thinking of vertical tile-battens with render board attached and render onto that with an airflow passage behind it.

 

Any help is VERY much appreciated.

[Russell griffiths]

Go and get a length of anthracite coloured upvc facia, use this as a mock up. 
cut a couple of pieces to cover that wood up 

try fitting flush to the wood and see how it looks with the render

try adding a 25mm batten to that timber then the upvc, see what you think. 
 

if any of these ideas are good i would then chuck the upvc away and get the profile you want bent up and powder coated 

render comes upwards and finishes with a stop bead against the aluminium, get a coloured stop bead, or spray them, unless your having white render of course. 

[Oz07]

Presumably this timber showing around the edge is no less ventilated than any of the other pieces? That section shows another piece inside of this.  Good question though I bet most people would just cover it up without a thought. 

[Mulberry View]

3 hours ago, Russell griffiths said:

Go and get a length of anthracite coloured upvc facia, use this as a mock up. 
cut a couple of pieces to cover that wood up 

try fitting flush to the wood and see how it looks with the render

try adding a 25mm batten to that timber then the upvc, see what you think. 
 

if any of these ideas are good i would then chuck the upvc away and get the profile you want bent up and powder coated 

render comes upwards and finishes with a stop bead against the aluminium, get a coloured stop bead, or spray them, unless your having white render of course. 

 

All very well, but there's about 60 metres to do. It'd have a lot of joins too.