Filling deep hole in wall next to window

[Xzam]

Hello,

I tried fixing a curtain bracket next to one of our windows but couldn't get any hold. Exploring further it turned out that there was rotten wood and hollow space behind it. So I continued and removed the plaster covering the hole.

There were dry wooden bits in it and plaster. I removed all of that and reached solid brick at the back of the whole (around 14 cm deep). I assume the wood is from the transition between window frame and wall. The window frame has seen better days (and probably we'll have to get the entire thing changed at some point next year).

In the meantime I would like to fill this hole so that I can finally put that curtain bracket in.

My original idea was applying something like this https://www.screwfix.com/p/ronseal-big-hole-ready-mixed-wall-filler-grey-1-2ltr/95289 but given the depth and size of the hole I would probably have to apply loads and in 3 layers (as maximum application is 50 mm).

The other thought I had was cutting a piece of wood to fit into the wall, fix it to the bricks with an anchor and then apply the filler on top of it and around it. Would just have to be careful to not place the "anchor" screws where I want to put the screws for the curtain bracket.

Would be good to get your suggestions and what you would do in this case.

Some photos below

Before opening the hole further (one piece of wood from inside)

Solid brickwall in the back

Depth: 14 cm

The window is to the right. Can see that the general wood of the outer window frame is not in a good state.

 

[RandomGrinch]

Hi,

I'm only a DIY'er so feel free to ignore!

I'm afraid I have a slight concern for the hole!
What age is your house and is that an external window?

On my Victorian house, I have a rubble filled stone wall. Above the window, the external skin of stones is supported by a brick arch, while the internal skin is held up by a wooden lintel. Something like:



My concern is, the rotten wood may be part of that internal lintel, or may have been part of the window frame supporting that lintel.

In your second picture, at the top of the hole, there looks to be a wooden beam (could this be a lintel?); as far as you can see, does that extend over the top of the window, and is it supported by anything else?

As I say, I am a DIY'er and could be wrong.
I'm sure others may have differing opinions!

p.s. You may want to move this post to the 'Building' section, if it is a structural issue.

 

[doog442]

Likewise not an expert but I've had a few random holes to fill over the years and used filler foam . You can sand the foam but I found it easier to apply a normal filler to smooth once the bulk of the hole had been filled with foam.

https://www.screwfix.com/p/soudal-gap-filling-foam-hand-held-750ml/46137

 

[RandomGrinch]

Likewise not an expert but I've had a few random holes to fill over the years and used filler foam . You can sand the foam but I found it easier to apply a normal filler to smooth once the bulk of the hole had been filled with foam.

https://www.screwfix.com/p/soudal-gap-filling-foam-hand-held-750ml/46137

As above, if there is no structural issues, then yes use foam.
And if you do want to attach a curtain bracket, foam in a wood block

 

[Xzam]

Thanks for your replies @RandomGrinch and @doog442 . I think you may be right about it being a lintel but for now, at least from my amateur point of view I don't see structural problems. And as mentioned, looking to get the whole window (a patio door) replaced in the next year anyway which could then involve assessing and fixing the lintel. There seems to be another beam which is quite solid above it. So maybe it's just a non load-bearing beam. The property is Edwardian, so might well be that it is constructed in a similar way to yours.

I think the idea with the Filling Foam sounds good. How would you go about foaming in the wood block? Would you still screw the wood block to the brick behind, then apply foam filler around it and then finish with surface filler?

Thanks

 

[RandomGrinch]

If you can see the beam above looks good, then that's probably fine for now!
The rotten one might be part of the window framing, and not the main lintel.

For the wood block, fix it in any way you can.
I would use low expansion, adhesive foam.
It is good enough to put a thin layer around the block, and that will be sufficient to hold it in place. Once cured, you can then fill up the gaps around the block.

If the block is set back a small distance, a piece of plasterboard could sit on top, flush with the wall. Then just use filler.
You may get some cracking at the joints, but hopefully, that will be hidden by the curtain and pole!

Good luck

 

[Xzam]

Just wanted to report on what I ended up doing in the end:

• bought some adhesive foam as suggested
• took some leftover and cut multiple wood sheets into the shape of the hole and screwed them together
  

• applied a base layer of foam and some smaller base plates to the back of the hole so that I have a reasonably even surface to glue the big block against
  

• after letting that cure cut of the excess and applied more foam to then set the big block
  
• after that cured fill in some of the remaining gaps with foam, then let that cure. Then I applied fine surface filler
  
  
• then sanded the surafce filler and finally painted over directly in the wall colour
  
  
  Pleased with the result and the curtain bracket is finally mounted. Thanks for your suggestions guys

 

[RandomGrinch]

Good result!
...and thanks for updating us