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Barron747
Mar 1, 2008, 07:41 AM
I need to vent an bathroom exhaust fan in the attic. Can I run the duct up close to the roof ridge that is vented. I have no way of venting it to the outside wall since the bathroom is in the middle of the house

hkstroud
Mar 1, 2008, 08:09 AM
Should be all right. How about venting through soffit? Probably be better and easy to do.

Barron747
Mar 1, 2008, 02:22 PM
I can't get to the soffit. The angle of the roof and blown in insulation would be tough

hkstroud
Mar 1, 2008, 03:05 PM
OK, go for the ridge vent.

If you want to "box it in", you could just put a piece of plywood 12 to 16" wide with a hole for the pipe, in between two rafters, laying on a couple of firring strips affixed to the rafters.

massplumber2008
Mar 1, 2008, 05:18 PM
Hi Guys.

Hey, they make a soffit vent kit (available in duct work section of home depot) that only requires you to cut a hole in soffit and then install the flapper assembly. Pretty cool... I use all the time.. and inspectors like it, too.

Just my two cents.

Barron747
Mar 2, 2008, 06:39 AM
I do not have a soffit on that side of the house nor could I get to it because of the pitch of the roof. I just need to know if it is OK to vent it into the attic close to the ridge of the roof line that is vented

the1unv
Mar 2, 2008, 07:07 AM
I have used a 10' piece of PVC pipe to gain access to the soffit on several occasions. The only thing you need to watch for while venting through the ridge is moisture. It may cause some condensation issues, especially in cooler months. I would hook a short piece of flex tube to PVC and push it out to the soffit on one side of the house or another. Cut your soffit hole from out side, locate your flex tube, attach it to your vent (as massplumber2008) has suggested and you are in business. I hate to vent anything into the attic, I have seen a lot of "do it yourselfers" vent things in such a manner. Some have problems, some don't. I wouldn't want to take a chance.
Mike

amricca
Mar 3, 2008, 10:08 AM
You could use a thru-wall fan if you are worried about venting into the attic / have no soffit to vent to.

ballengerb1
Mar 3, 2008, 01:05 PM
I have to admit I have seen many builders vent fans to the soffit but this is very poor quality workmanship and it should not be done. You do not terminate a vent in the attic or the soffit. You need to vent through an outside wall or through the roof. You need to get the moist air to the exterior of the house. If you vent into the soffit the soffit just allows the moisture to reenter the attic. I know that many folks may differ with me on this one but believe me, the vent must terminate outside the house. The builder I see doing this tell me it's the way they have always done it, doesn't mean its correct though.

the1unv
Mar 3, 2008, 05:06 PM
I would like to point out that I never said to terminate in the soffit. They make vents that you cut into the soffit. The vent is cut in toward the very out side edge of the soffit. The soffit vent has fins that lay at an angle and direct the moisture past the edge of the soffit. This is a very common practice and a long way from poor quality workmanship. If I were building a new house it would be different,however, in a "do it yourself" situation I would much rather see an inexperienced person cut a hole in their soffit verses their roof.
Mike

ballengerb1
Mar 4, 2008, 02:26 PM
I apologize for not being more clear with my answer. I have seen way too many builders vent TO the soffit. They did not use a vent kit but ran a rigid 3" pipe to the soffit and added a 90 degree elbow down to the soffit intake. That is the shoddy part. Remenber folks the soffit lets air into the attic by convection year round. We do not run plumbing vent stacks to the soffit for the same reason.

Raymonator
Mar 15, 2008, 04:32 PM
I would like to point out that I never said to terminate in the soffit. They make vents that you cut into the soffit. The vent is cut in toward the very out side edge of the soffit. The soffit vent has fins that lay at an angle and direct the moisture past the edge of the soffit. This is a very common practice and a long way from poor quality workmanship. If I were building a new house it would be different,however, in a "do it yourself" situation I would much rather see an inexperienced person cut a hole in their soffit verses their roof.
Mike

Could someone use the same type of exterior vent used on cloths dryers (which also has fins that flap up when the dryer is on)
Also, if I understand you correctly, the hole for that bathroom fan vent, is made my cutting into the vertical 2x whatever on the lower cable part of the roof ?
My bathroom fan right now is connected to a flexible accordion stye pipe and just lays in the attic on top of the insulation. (Previous owner) I haven't had any problems with condesation, but would like to remedy the situation.

massplumber2008
Mar 15, 2008, 04:49 PM
Raymonator they make soffit vent kit for your situation (sold at home supply stores in ventilation isle).

Run flexible vent , as in dryer vent, and then install at soffit. Cut hole in soffit and install soffit vent.

This vent is different from regular dryer vent in this application as opens and closes at 45 degree angle The regular dryer vent would just hang down (and open) all the time. Let me know what you think... Mark


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elo35
Dec 17, 2009, 10:18 AM
I have my bathroom fan vented to the side of the house and the vent on the outside has a screen to prevent birds and bat from entering but the flapper that closes the vent (on the outside) does not close all the way and that will let bugs into the duct work. How do I get an outside vent that will closes and prevent both birds and bugs into it? The vent is on the side of the house not the roof or soffit.