bathroom fan into attic

Jun 8th, 2021 9:22 am

#1

fred999 [OP]: Sr. Member; Mar 3, 2009; 503 posts; 35 upvotes

Jun 8th, 2021 9:22 am

I was thinking about putting in a fan in the bathroom, exhaust into the attic.

But I`m wondering about sending humid air into the attic - doesn`t seem like a good idea.

It would probably be better to connect to one of the vents in the roof.

Does anyone think it would be ok to just vent into the attic, without connecting to a roof vent? Could the attic handle a bit of moist air?

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Jun 8th, 2021 9:27 am

#2

coffeeguy: Member; Apr 14, 2009; 237 posts; 116 upvotes; Vaughan

Jun 8th, 2021 9:27 am

You will be creating a mold factory, it needs to be vented out of the attic.

+6

Jun 8th, 2021 10:00 am

#3

l69norm: Deal Expert; Jun 12, 2007; 16403 posts; 5140 upvotes; London

Jun 8th, 2021 10:00 am

$$$$$ mold remediation = remove / replace shingles + remove/ replace roof decking plywood + remove replace attic insulation + seal wood trusses

Bathroom fan needs it's own dedicated / sealable vent thru the roof

Last edited by l69norm on Jun 8th, 2021 10:50 am, edited 2 times in total.

+2

Jun 8th, 2021 10:02 am

#4

hammer: Deal Addict; Oct 4, 2001; 1404 posts; 71 upvotes

Jun 8th, 2021 10:02 am

how about out the wall

All is not golde that outward shewith bright...lydgate

Jun 8th, 2021 10:07 am

#5

drey: Deal Addict; Sep 13, 2003; 1283 posts; 112 upvotes

Jun 8th, 2021 10:07 am

definitely a bad idea to vent to attic.
im not an expert but i think based on my prior search about venting, out to the wall may not be a great idea if your vent is close to your soffits as the moisture can creep back into the attic. best is to vent out the roof, you're saving your family and wallet from any unneeded financial expenses for repairs

+1

Jun 8th, 2021 10:09 am

#6

walleye*guy: Deal Addict; Mar 30, 2004; 2344 posts; 1065 upvotes; Edmonton

Jun 8th, 2021 10:09 am

Your fan has to vent to the outside. Through the roof or through a wall, doesn’t matter. Do not use an existing vent unless there is nothing else attached. Not hard to put a new vent in a roof.

The bitterness of poor quality remains long after the sweetness of low price is forgotten....

+1

Jun 8th, 2021 10:27 am

#7

ds2chan: Deal Addict; Dec 11, 2003; 2415 posts; 987 upvotes; Toronto

Jun 8th, 2021 10:27 am

I saw one of those reno shows on HGTV and the contractor said bathroom fans have to be vented outside. That's all I know about bathroom fans. I'm not sure if it has to be horizontal to the ground or just outside at the closest spot on the roof though.

If you don't know stuff like this shouldn't you hire somebody to do this for you (instead of guessing)?

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"You're only as dumb as you look"

+1

Jun 8th, 2021 11:28 am

#8

BDSL: Deal Addict; Sep 22, 2009; 2020 posts; 670 upvotes; Markham

Jun 8th, 2021 11:28 am

Always vent outside or you risk mold inside your attic.

+1

Jun 8th, 2021 11:30 am

#9

golden: Deal Fanatic; Jan 15, 2004; 6592 posts; 1137 upvotes

Jun 8th, 2021 11:30 am

Must not vent into the attic. Definitely will have mold issue. Connect it all the way to the roof and install a vent. You can also have the vent comes out on the side depending on your house. My basement bathroom vents to the side of the house.

+1

Jun 8th, 2021 12:15 pm

#10

TLSRULZ: Deal Addict; Apr 18, 2005; 2611 posts; 992 upvotes; Mississauga

Jun 8th, 2021 12:15 pm

hammer wrote: ↑ how about out the wall

If its the second floor , roof is the new normal. I had mine venting into the soffit.. and when I did my home inspection the inspector made a note of it. When we did the bathroom reno, I got it redone into a roof vent.. Contractor said it was just flexible dryer hose that was just sitting on the soffit loosely held onto the fan.. he just touched it and it all came off...

+2

Jun 8th, 2021 12:47 pm

#11

BDSL: Deal Addict; Sep 22, 2009; 2020 posts; 670 upvotes; Markham

Jun 8th, 2021 12:47 pm

You will need an insulated hose. You don't want condensation collecting inside the hose.

+2

Jun 8th, 2021 1:12 pm

#12

davidmr: Member; Sep 29, 2015; 277 posts; 81 upvotes; Winnipeg, MB

Jun 8th, 2021 1:12 pm

fred999 wrote: ↑ I was thinking about putting in a fan in the bathroom, exhaust into the attic.

But I`m wondering about sending humid air into the attic - doesn`t seem like a good idea.

It would probably be better to connect to one of the vents in the roof.

Does anyone think it would be ok to just vent into the attic, without connecting to a roof vent? Could the attic handle a bit of moist air?

Do you have a HRV or ERV that is ducted to the bathroom?

Jun 8th, 2021 2:25 pm

#13

fred999 [OP]: Sr. Member; Mar 3, 2009; 503 posts; 35 upvotes

Jun 8th, 2021 2:25 pm

Thanks everyone - out the roof will be the way to go... then I`ll need to trust the guy to seal the vent properly to prevent leaks

Jun 8th, 2021 2:45 pm

#14

GoodFellaz: Penalty Box; Jun 24, 2015; 4954 posts; 1490 upvotes; 0 downvotes

Jun 8th, 2021 2:45 pm

i had a dryer vent that came loose and was not just venting hot air in the basement ceilings but also left a huge messy pile of lint everywhere, in every nook and cranny of my basement ceiling took for ever to clean

Hi