fitting an extractor fan in isulated walls

[graduate_owner]

Hi all,
my daughter has asked me to install a 6" extractor fan in her bathroom. No problem, except the walls have been filled with loose polystyrene beads and if I just drill a series of holes and chisel out the core, I'm expecting a shower of beads and then cold spots in the walls. Any ideas how I can avoid this?

K

 

[MMUK]

What size is the duct? If it's 4" or 6" I'd core drill 110mm or 165mm respectively and fit a piece of underground soil pipe as a sleeve from inside to out.

 

[n0legs]

Find the spot for where the extractor is needed and drill a 10mm hole in 4 places through to the cavity, inject a can of expanding foam. Return the next day and cut a hole for the fan.
We used to use this method for installing meter cabinets in insulated walls, easy and very effective.

 

[dickm]

Find the spot for where the extractor is needed and drill a 10mm hole in 4 places through to the cavity, inject a can of expanding foam. Return the next day and cut a hole for the fan.

Sir, you are a ***** genius. Wouldn't have thought of that in a month of Sundays.

 

[graduate_owner]

I'll second that - what a brilliant idea. I'm sure a lot of readers will benefit from that little gem.
Thanks very much mate.

K

 

[n0legs]

Sir, you are a ***** genius. Wouldn't have thought of that in a month of Sundays.

I'll second that - what a brilliant idea. I'm sure a lot of readers will benefit from that little gem.
Thanks very much mate.

Thanks guys.

 

[mind_the_goat]

Find the spot for where the extractor is needed and drill a 10mm hole in 4 places through to the cavity, inject a can of expanding foam. Return the next day and cut a hole for the fan.

Genius =D>

 

[ColeyS1]

That's really clever. There nearly needs to be a thread of 'things expanding foam is usefull for' besdides the obvious gap/ draught proofing.....

Cheers
Coley

Sent from my GT-I9300 using Tapatalk

 

[graduate_owner]

Followed by a thread on uses for duct tape

K

 

[Mark A]

There was a thread on here a year or two back where people submitted their hints and tips. By any chance has anyone bookmarked it? This expanding foam trick should be added to it!