I have this hole in the wall to outside with cables for the ACs.

This is in a high floor condominium. We don't have rats or any other such animals outside on the high floors.

I want to close it for better isolation. What is the best way to do this? 

Should I use PU foam spray? Any other ideas?

 

I suggest filled up with "insulation wool", easy to remove when u need to replace the aircon(s)

Can you access the "hole" from both sides, if yes I would suggest expanding foam that can then be trimmed up after curing. 

1 hour ago, Artisi said:

Can you access the "hole" from both sides, if yes I would suggest expanding foam that can then be trimmed up after curing. 

In theory it's possible that someone can do that. But I am not brave enough to do that at about 100m height. 

1 hour ago, rgrdns said:

I suggest filled up with "insulation wool", easy to remove when u need to replace the aircon(s)

Thanks, that sounds like a good idea.

The ACs are new, and likely I will be able to use the same cables again even with new ACs. But in principle I like when things are service friendly. And isolation wool is certainly easier to remove compared to stiff foam. 

A 100m high jeeze is it a condo? that  would be like 25 floors high.

1 hour ago, brianthainess said:

A 100m high jeeze is it a condo? that  would be like 25 floors high.

Imagine, there are even condominiums with 30 or 40 floors and even more...

 

On 2/16/2024 at 9:33 AM, OneMoreFarang said:

Thanks, that sounds like a good idea.

The ACs are new, and likely I will be able to use the same cables again even with new ACs. But in principle I like when things are service friendly. And isolation wool is certainly easier to remove compared to stiff foam. 

There wouldn't be much problem removing the foam, breaks up quite easily.

The bigger problem with the foam is getting it into the hole. The can is above the spray nozzle and upright, with aircon being close to the ceiling it can be difficult to get good access to the hole. When I did mine I sprayed on to a trowel and then filled the hole.

2 hours ago, OneMoreFarang said:

Imagine, there are even condominiums with 30 or 40 floors and even more...

 

Did you use a crane to take the photo?

What a sad photo that is.

 

Not one piece of nature available to the naked eye. Just concrete, glass, and about one million people. 

 

You could cover the hole with tape, then move onto the windows. 

On 2/16/2024 at 9:33 AM, OneMoreFarang said:

And isolation wool is certainly easier to remove compared to stiff foam. 

What is "stiff foam"? Some product they use in funeral parlors?

17 hours ago, Ben Zioner said:

What is "stiff foam"? Some product they use in funeral parlors?

or used in soapy massages?

Not done a 100m high fill before, but would use a fire rated expanding foam over insulation wool. Logic being, easier for weathering to remove the wool on the outside creating a niche for further avian erosion for nesting. Would second  @sandyf's trowel idea or wear a plastic glove to build up the hole rather than just nozzle it.

💡 Stick a large balloon in the hole and fill the balloon with foam. 

23 hours ago, brianthainess said:

Did you use a crane to take the photo?

Looks like the view from Marriott 57 Octave roof bar