The fan in the bath of a townhouse I’ve recently moved into seems underpowered. Looking in the attic I found that the fan vents through dryer hose to one of the roof vents. It comes close to the vent but is not a dedicated exit for the warm moist air from the bath. Here in northern Illinois I don’t think it’s a problem in the winter but what about the summer? Am I just introducing moisture into a hot attic? Is this set up code? Should I enclose the hose to the vent to make it a dedicated exit? Thanks for your thoughts.
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Its code to let it exit in the attic . Does not need to be vented outside the structure.
The hose is to get it above the insulation .
Tim
Which code?He is in North IL, which is possibly Chicago area land. And they don't use "normal codes". I would not be surprised to see then require SS ductwork and wet stamped analsyis by a mechanical engineer as the amount of air that it will move.But even IRC2000 does not allow this.The bathroom either needs an openable window OR a mechanical ventalation EXHASUTING DIRECTLY TO THE OUTSIDE..
.
A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
We do um all that way here in vented attics. No biggie.
I dont remember the code but I had to check for it .
Tim
Edited 9/8/2008 3:24 pm by Mooney
Worse in the winter. Moisture will condense out of the air and "rain" inside the attic.
Hook it to the ridge vent if you have one.
Chuck S
Bath humidity vented in proximity to cold building materials (like roof members in an attic) is a recipe for condensation and rot. If venting into an attic is not against code, it should be. (I never even remotely thought of doing this, so I never felt the need to look it up.)
You sound like you have two problems: 1) underpowered fan, leaving too much humid air in the bath area which can lead to mildew, rot, etc. in that area; and 2) improper venting.
If it wuz me (and it ain't), I'd be looking to install a new fan (I really like the Panasonic in-lines, since you have an attic you can locate it in) and properly venting it through the roof or gable.
Mike Hennessy
Pittsburgh, PA
In the Pacific Northwest this was absolutely not acceptable to not have a positive direct connection to a vent boot through to the exterior. NO ATTIC TERMINATIONS ALLOWED. Had many discussions w/ building inspectors ...
It's a bad idea ... winter wise as one other said. Warm moist air will condense on that sheet metal boot and freeze. I've seen softball size ice on roof nails because of poor attic ventilation .... then when it warms up you have some serious problems.
Solution? Definately direct connect to the boot and seal it!! Also, if your duct is mostly flex duct ... get rid of it as much as possible and do a hard duct up to the boot. Flex duct is nothing more than restricting air flow. Use it ONLY where you need to otherwise avoid it! Small puny bath fans need all the help they can get to do their job. Another option would be to upsize your fan cfm from say the little 20-40 cfm to say 80 ... or even connect multiple baths to a common fan in your attic ... like a nice Panasonic super quiet high volume fan. I bought one for about $120 ... 250 cfm. Can't even tell it's on. I like it! ... I tied it to 4 outlets and 3 switches ...