Replacement bathroom fan

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Replacement bathroom fan

Post by Nilzor » Sat Mar 16, 2019 2:09 pm


I am replacing the old bathroom ceiling fan and had to remove the whole housing unit.

I was able to get the old one out but now I realized the vapour barrier is not intact. Me yanking out the fan didn’t help, but to me it seemed this wasn’t properly installed to begin with.
I also noticed the insulation to be moldy.

- can I live with this or is it advisable to remove the drywall ceiling and re-do this?

- if I only line the hole for the new fan with 6mil sheathing how do I manage to efficiently plug the hole for the duct and electrical?

Thanks for any advise,


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Re: Replacement bathroom fan

Post by markbrown » Tue May 07, 2019 5:20 am

would you share some photos so that i can have complete idea.

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Re: Replacement bathroom fan

Post by Shannon » Tue May 07, 2019 7:11 am

Do you have access to the fan from the attic? It will be easier to install a vapour barrier usually from the attic than to remove and replace all the drywall as well if you don't need to. Most times people never did anything more then cutting the vapour barrier around the fan and taping it to the housing. The problem with this method is that the housing its self has a few holes in it and is not sealed.

What you are seeing as mould may actually just be dirt and dust on the insulation because of air flow in that area where there was a poor air/vapour barrier?
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