I am seeking a solution to a pretty serious mold problem. I recently bought a 1800 sf ranch that has a large front porch that is covered by trusses that overhang from the front of the house. The problem is that two bath fan vents come out in the porch ceiling and the dryer vent comes out of the rim also under the porch. The moist air from these vents is getting sucked up through the soffit vents at the outer edge of the porch and is condensing(and by the looks of it has been for a long time) on the back of the roof sheeting. The first two pieces of plywood are black and furry.
So here is my question: I plan on replacing the roof plywood, and reroofing the whole house. Where do I route the vents from the two bathroom in the front of the house and the dryer?
We get a lot of snow here and I don’t want to go out the roof and have the vents get buried by snow. I figure the warm exhaust would melt it and cause ice dams.
I also don’t want to go out the gable end because the house is log and I dont want water running down the logs either.
Am I stuck or is there a good solution to this. I love the house and want to stay for the long haul.
Thanks in advance for any help.
Replies
If you can wait a month...........
and want to invite a boatload of Breaktime Festers over for a cold one..............
You can benefit from some pretty ingenious minds to physically scope out your problem.
This years Fest-Saratoga Springs-July16, 17, 18th with a boat cruise of Lake George on Saturday.
If nothing else, you should attend. Check the Fest Folder here.
We get a lot of snow here and I don't want to go out the roof and have the vents get buried by snow. I figure the warm exhaust would melt it and cause ice dams
Even if the roof exhaust vents get buried in snow, they don't usually cause ice daming. Ice daming occurs because the attic air temp. raises high than the freezing outside air temerature and the roof deck warms from the inside. The resulting thaw water then travels down the roof untill it hits the colder roof overhang and soffit area, where it refreezes to form the ice dam. The exhaust from a bath fan in a properly vented and insulated attic will probably freeze within a foot or two of the vent and then thaw at the same rate as the surrounding snow cover.
I would reroute the fans to a higher point on the roof and make the roof pentration. Also reroute the dryer evnt to get it out from under the porch. That location is a prescription for a messy buildup of moisture and lent under the porch deck, (BTDT) The lent isn't a big deal if you can easily get under there durring the warmer seasons and clean it out, but if not it becomes tinder, and a big spong for any moisure trapped down ther. Plus little furry creatures love to nest in it :)
Roof vent
I thought about the ice dams because the bathroom ceiling fans are only a couple of feet from the front wall of the house. But, I never thought about going higher up the roof with the outlet. Thanks for the tip.
I am thinking about getting a more powerful inline fan and combining the two bath fans into one outlet higher up on the roof.
With the dryer, I am thinking I will just go the opposite direction and out the rim in the back of the house which has no overhang or deck. Should I close the soffit vent in that area above the dryer vent or is that overkill?
Thanks again.
Wood
Wire two timer switches (pushbutton-10,20,30 minute) to the remote fan. Moving warm moist air first and allowing the humidity in the room to get back to normal is a good idea. It clears the exhaust of the most moisture laden air. People that turn on the fan while showering and then shut it off when done will have more problems with excess moisture in that attic piping-condencing and maybe pooling/leaking where you turn to go up.
And unless it's an A-frame with the roof run to the ground, your soffit vents won't passively pick up the dryer exhaust
Thanks for the help. I think I will do exactly that with timer switches in both bathrooms and a inline fan in the attic. Venting out through the roof up higher.
I will route the dryer vent out through the rim in the back of the house with a straight run of smooth metal duct. The soffit vent will be 8 feet above that, so should be no problem.
The amount of furry mold on the roof plywood right now is disturbing. It is like a science experiment up there. I just want to make absolutely sure to avoid that in the future.
That sounds like a good plan. I tend to agree w/ the other posters. Even a gable end vent shouldn't result in 'water running down the side of the house' (generally speaking).
I used some nice Panasonic in line fans. like 250 cfm I think. Cost me $100 each and both served 2-3 rooms. VERY quiet. Very nice. The timer switches are perfect. Whoever is in whichever room simply sets the timer for what they need. If someone in the other room comes in 10 minutes later and sets theirs for 30 minutes, their switch shuts the system off.
Make a point of contacting Mike in Saratoga
Take a look at the RezFest thread in the Fest Folder and use the link to the Fest page-all the info is there.
A great opportunity to meet up with some of the people you sort of know here. A real good time for sure.
I have never seen a roof pentratig exhaust vent cause a problem, when installed right.
I live in a log home and find no problem with water running down logs from the dryer vent. That moisture disperses away into the atmosphere.
Now lint though, is another thing - you get to see a pattern grom the clingers
Thanks, Piffin.
Enjoy Saratoga/Lake George it is a great area. My family and I really love it.
I gotta ask....
Are you really 34 years old and retired? Or is that just a fantasy?
Yeah, well kinda
I am officially retired from my former career in sports, but I work part-time for money and more than full-time on this darn house.