EWI Window Reveals

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FreeD

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I read recently a report cold bridging on EWI window reveals (where they aren't insulated, rest of the wall is) can reduce the effectiveness of a system on a house by upto 60%.

So I'm curious how do installers get over this...

Do they replace the windows for windows with wider frames? Bring the windows to the front of the opening? Cut back the brickwork around the window? Or is there some kind of super thin 10mm insulation available?
 
How wide is the frame? There are thinner boards you can use like 20mm for instance. Otherwise go as far as you can over the frame. Use foam instead of adhesive if necessary which will give you more space.
 
If you decide to use adhesive,spread it nicely over the reveal and put the board after. The thin ones are very easy to brake.
 
I read recently a report cold bridging on EWI window reveals (where they aren't insulated, rest of the wall is) can reduce the effectiveness of a system on a house by upto 60%.

So I'm curious how do installers get over this...

Do they replace the windows for windows with wider frames? Bring the windows to the front of the opening? Cut back the brickwork around the window? Or is there some kind of super thin 10mm insulation available?

10mm would do nothing at all. In fact it would be too flimsy to be part of a system that needs warranty over a 25 year period. 25/30mm boards are available but ideal to have the window re-placed. Im not sure 60% less performance is a real figure either. Windows on the whole a weak link if not upgraded
 
One of our current projects is ewi on a grade 2 listed house, we've got away with altering the outside with ehi, in that it's the same colour as the existing render, but they aren't changing the wood frame Windows, so regardless of the 90mm eps going on, the heat will just escape through the frames, some people won't be told.
 
We use a rigid 25mm foam board for reveals can't recall the manufacturer, but it's the same u value as 50mm phenolic.
 
One of our current projects is ewi on a grade 2 listed house, we've got away with altering the outside with ehi, in that it's the same colour as the existing render, but they aren't changing the wood frame Windows, so regardless of the 90mm eps going on, the heat will just escape through the frames, some people won't be told.
And when they realise and change the windows.......Oh dear lol
 
Problem is when your dealing with architects it's like banging your head against a wall, they seldom change there way of thinking.
 
Most of the Victorian houses I re render have around 20mm max to the window, it's hard enough getting the beads on, I still haven't offered insulated systems externally as I don't want to waste my time pricing it up and not getting them...allowing for new windows, new pipework, eaves extended, meter boxes moved, stonework reinstated, cills capped....
 
20mms enough with a thin coat, but not ehi.
to sell ewi to a private customer, they have to be half convinced on the idea before you even walk through the door.
 
on the back edge of the reveal we apply a coat of thermorend then scrim over the reveal.
 
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