Insulation and ventilation

[Idiyh]

Hi everyone,
I'm trying to insulate the gap between the sunken gas box that depresses into the wall outside and the inside of the property.
It looks like whoever did it smashed the bricks and so there is a void.... Can you advise how to do it. Thankyou
The first 3 pictures are under the kitchen units. How best is it to insulate these areas while still providing adequate ventilation please?
Thes last picture shows the void... Pictures might explain better.

 

[foxhole]

Just sand cement mix. No point insulating under kitchen units.

 

[JohnD]

Except to stop cold draughts

 

[Idiyh]

Except to stop cold draughts

Thankyou... I don't get drafts it's just cold... Its so frustrating... Any idea how to keep it warmer behind the units

 

[Idiyh]

Just sand cement mix. No point insulating under kitchen units.

Hey foxhole,
Thing is, is there is a big void where someone previous has put little white like polystyrene balls in the gap... Seems useless looking at it.
Any ideas to build on what you said... Thankyou

 

[foxhole]

Hey foxhole,
Thing is, is there is a big void where someone previous has put little white like polystyrene balls in the gap... Seems useless looking at it.
Any ideas to build on what you said... Thankyou

The white beads are probably cavity insulations spilled when the hole through the wall was done.

 

[Idiyh]

The white beads are probably cavity insulations spilled when the hole through the wall was done.

Looks like you are on the money.... So my next question is how to contain them and close it up without bridging gap for cold and damp to cross?
Thankyou

 

[foxhole]

Like I said sand cement, you won’t get bridging across beads.

 

[Idiyh]

Like I said sand cement, you won’t get bridging across beads.

Thankyou,
So in the picture the RED lines indicated the gap width that travels down the wall.
The BLUE line indicates the smashed electric BOX. Where do you suggest to seal it up because the mortar would simply fall in the gap?
Thanks

 

[foxhole]

Wet mortar sticks, you could add a thin sheet of timber to seal the box.

 

[Idiyh]

Wet mortar sticks, you could add a thin sheet of timber to seal the box.

Foxhole.... Imagine you are looking 90 degrees down a cavity wall. If you Mortar it perpendicular to it, it falls in.
Do you think it's also a good idea to pack it with polystyrene balls too?
Thankyou

 

[Idiyh]

Hey guys, do you recommend filling this hole with micro insulation beads and then putting some kind of thin ply over the hole to prevent drafts and bugs and anything getting in?
I want to seal it properly but not bridge the cavity gap otherwise moisture will travel across it right?
Thankyou

 

[Mr Chibs]

Expanding foam then.

 

[Idiyh]

Mr chips... Think about it.... The house cavity spreads all round the house, so the endless foam I would need is unimaginable..... Any other ideas please that might actually work?

 

[Deleted member 174758]

Sand and cement? Oh-oh, I see @foxhole already suggested that