Screwing loose uPVC window to walls

[Oxbow16]

17 minutes ago, craig said:

It’s for exactly the reason mentioned, vertical DPC is “usually” installed and used to stop water travelling sideways.

 

I’m not a fan of it, as that means if water is getting to the point the vertical DPC is stopping it travel sideways. Then it has to travel somewhere and just shifting the problem rather than preventing the problem (if a water issue exists).

 

Hi Craig

 

Thanks for joining it and sharing your expertise   

 

Not a fan of it, but do you hate it enough that you would take hammer and chisel to the reveals and get it all out?  I hope not because that sounds like quite a big job!  And it's not the only window that has it.  Assuming for a moment that you're not proposing that and that whilst not ideal it's there now and so must stay, how do I do about doing the filling and foaming around the window?  Should the DPC you can see be on the outside side of the foam etc (pressed against the frame?), or on the room side?  The reveal is going to be tiled in the next week or two, so what foaming/filling I do will be the stage one to the stage two of tiling.  

 

Thanks for your help.  

[craig]

34 minutes ago, Oxbow16 said:

do you hate it enough that you would take hammer and chisel to the reveals and get it all out? 

No, leave as you’ll create bigger problems.

 

34 minutes ago, Oxbow16 said:

Should the DPC you can see be on the outside side of the foam etc (pressed against the frame?), or on the room side?

DPC should be bridging the cavity, some will attach to the side of the frame. Your wanting the foam to fill the void.

Edited November 20, 2021 by craig

[Oxbow16]

3 minutes ago, craig said:

No, leave as you’ll create bigger problems.

 

 

Thank Jesus, Buddha and Mohammed for that!

 

 

4 minutes ago, craig said:

DPC should be bridging the cavity, some will attach to the side of the frame. Your wanting the foam to fill the void.

  

Right, I think I get you.  So in the last two photos I'd be foaming/filling to the left of the DPC?  And the order of things looking from left to right would be - reveal, foam, DPC, window frame.  Is that right.  So to be el thicko, but I keep drawing a blank when I try to think about it logically myself!  

 

As for the large deep gap, I was thinking of using mortar for that.  Or could foam be used there too?  Wasn't sure if it was too large for foam.  Thanks again for all the help and guidance.

[craig]

Foam behind / in front of the DPC, sorry was looking at picture on phone so not a massive screen like the desktop I'm now on. The DPC should be to the other blockwork, to prevent transference to the inside, then insulatated (foamed). What they have done is put the DPC up the inside of the cavity (at least that's what it looks like). It's designed to prevent wet transferring from one porous material to another. Foam is used as an insulator.

 

The foam needs to be in front of the DPC. Was the DPC already in situ before replacing the window or did you put it in during the replacement? How it is shown, appears to show that the cavity is closed with blockwork or is the cavity fully open?

 

A good example

 

Ignore the arrow, it's pointing to issues with the DPC (i.e. there is none when there should be).This is another way to deal with the DPC by folding being the window and then foaming between window and DPC.

 

 

 

Edited November 20, 2021 by craig