help needed! Window reveal continued...

[Dougalogic]

Help please!
I am in the process of tiling a window in the bathroom and decided to pull out all the woodwork
(see http://www.tilersforums.com/tiling-forum/56647-tiling-window-reveal.html)
so I could put backer board in. However, I have now pulled out all the wood from the reveal and found the wall is a type of concrete cavity - the window being flush in the external skin. How the hell do I attach backer board when it will only be supported on the side nearest to me?!

 

[bugs183]

Can you bridge across the gap with some thin strips of galvanised metal such as wall ties? Can these tuck under the window frame?

 

[Dougalogic]

that might work but not sure how level it would be. also how to attach the board to the metal (especially up the verticals)?

 

[bugs183]

Mm bit of a tough one that as you're not supposed to bridge the gap. You may have to get some cavity closures from the builders merchants and use some low expansion foam to fix it all together, bit hard to say with no photos.

 

[Muse2k8]

Yeah if you can post some pics it will help.

 

[Mike]

can you fix a batten (horizontal) on the outside wall under the window then fix a cement board across the sill

 

[widler]

stick some DPC down the inside of the wall,next to the window,using sticks like REMOVED or other good adhesives,and cut some lengths of plasterboard and stick them on the DPC with drywall,making a plasterboard batton to stick your backerboard too with adhesive

 

[Dougalogic]

will try and get a pic tonight. a batten sounds best but could be tricky to get in at the outer wall. also the inner wall is something like a concrete fill and is no where near straight on the cavity side. also for this reason I'm not sure if a cavity closure would fit in..mind you I've never used one, is the bit that slots into the cavity foam? i.e. could I squeeze it in?

 

[Dougalogic]

stick some DPC down the inside of the wall,next to the window,using sticks like Removed or other good adhesives,and cut some lengths of plasterboard and stick them on the DPC with drywall,making a plasterboard batton to stick your backerboard too with adhesive

never used sticks like REMOVED, how strong an adhesive is it? Can I stick backer board to damp proof course with it?

 

[Muse2k8]

With sticks like "excrement" you could stick your wife to the ceiling and the ceiling would give way before the glue would!

It's magic stuff

 

[Gazzer]

With sticks like "excrement" you could stick your wife to the ceiling and the ceiling would give way before the glue would!

It's magic stuff

:lol::lol:

 

[widler]

With sticks like "excrement" you could stick your wife to the ceiling and the ceiling would give way before the glue would!

It's magic stuff

see,im just not clever enough to think to spell it like that

 

[Muse2k8]

It makes it clearer than REMOVED lol

 

[widler]

It makes it clearer than REMOVED lol

ha ha i know

 

[Dougalogic]

a couple of photos attached. may go for the gluing option as don't think my drill will be able to get through the concrete for a wooden batten. any other suggestions welcome!

 

[DHTiling]

Fill with expanding foam and then dry line onto that.

 

[Dougalogic]

thanks Dave. how solid is expanding foam? you reckon it'll be more sturdy than gluing a batten on the exterior wall?

 

[Dougalogic]

also, can you recommend a brand or are they all about the same? cheers
d