I’m doing two bathrooms – first and second floor. Second floor bath is right over the first floor bath. I have plan on a chase for the stack (common for both baths?) and figured that would be a great location for the vent fan.
If the fans are in separate pipes (down draft to the basement and then out) should I continue the two pipe confuguration all the way to outside or can they be brought together (conserving materials) at some point without one fan backfeeding the other vent?
Cheers,
Paul
Replies
Take a look at Fantech. One fan, two rooms.
A great place for Information, Comraderie, and a sucker punch.
Remodeling Contractor just outside the Glass City.
http://www.quittintime.com/
Calvin - thanks. That looks like the best option. Less "messy" instillation and with a remote fan, less noise.
There are fantech distributors here that are in the HVAC business. Perhaps a good source if they're helpful. Be able to fab up any "goofy" adaptations to the normal install.
Best of luck.A great place for Information, Comraderie, and a sucker punch.
Remodeling Contractor just outside the Glass City.
http://www.quittintime.com/
Thanks for the link. I've saved the pdf for future reference.BruceT
Anytime Bruce.A great place for Information, Comraderie, and a sucker punch.
Remodeling Contractor just outside the Glass City.
http://www.quittintime.com/
Yeah, I was going to mention the central fan option. Besides FanTech, there is American Aldes. Maybe some more. I think the Aldes one has electronic dampers now so that the it doesn't draw on all sources regardless of which switch is turned on. I also recommend the EFI delay switches.
If you have two fans feeding a common duct you should add external butterfly valves on the output of each fan. The fans themselves generally include flapper valves, but they aren't all that effective.
Be sure to insulate those ducts...the Fantech really draws the moisture out and will condense in the duct in cool weather.
I've been impressed with my FAntech rig...watching the little water vapor tornado under the light is worth the extra money for the fan!!!
Yeah I wondered about the example installation picture where they showed the flex line going straight up through the attic and penetrating the roof with no insulation. I would have thought the best place to exit would be the soffit so all the condensation will run out that way instead of back down into your bathroom. Insulation is also a great idea.
In theory, if the flapper on the fan closes securely when the fan is off, then there will be no condensation in the duct. In practice, theory sucks -- some air will generally leak through unless the house is somehow maintained at a vacuum.
People never lie so much as before an election, during a war, or after a hunt. --Otto von Bismarck
They sell insulated flex duct but it is pricey and the insulation is thin. I had a 10 foot run thru the attic, in the mountains of Maine, so I wanted a better blanket...just routed the duct across the rafters and and laid unfaced batts on top, like an A-frame. Simple cheap and it works. Pitching the uninsulated duct towards the exit might cause icing in the winter or water stains in summer. Seems better to keep the exhaust air warm all the way out of the envelope.
Condensation is the reason I'm thinking down and out. Through the basement wall as long as the snow doesn't get too deep!had not thought about the insulation. Good point.
It's also possible in many cases to run the duct between joists, then out the sidewall, allowing the regular attic insulation to cover the duct.
People never lie so much as before an election, during a war, or after a hunt. --Otto von Bismarck
Good point about the icing and water stains. The temperature I am used to goes below 0 celcius twice a year so icing isn't too much of a concern, water staining, depending on where the exit is, would be an issue.
When you are done running all your mechanicals, make sure you seal up that chase air tight. You do not want to have air leakage from basement to attic.
Hmmm. Another good point.I do expect to be insulating the chase as it will also have the vent stack contained - also running from the basement.Did I mention this is an old Victorian era farmhouse previously with no insulation? Soon to have six inches in exterior walls.
You do not need to insulate WITHIN the chase, unless it is an exterior wall. In that case an exterior wall as a plumbing chase isn't the best scenario. It is better to be an interior wall.
<deep breath> OK, what type of insulation will you be using in the exterior walls and in that attic?
Exterior wall , 6 inch deep , current 4" cast vent pipe not in wall but close to. chase would actually be in corner of room(s). Not in wall because of post/beam construction.fiberglass insulation planned.
Mech code says you can wye your fan ducts at the point of termination, but not before. Meaning if you use two fart-fans and run 4" for both down the chase, you can wye them together at the wall penetration, assuming after you get out the wall you've immediatley got your flapper.
Just a consideration. Hot air, and steam rises. Any problems with trying to push it down? I always vent out the roof.
-duke
"A wrongdoer is often a man who has left something undone, not always one who has done something."--Marcus Aurelius
Had not thought about possible problems with down and out.With the "Fantech' arrangement the air would be drawn down rather than pushed.
I really don't know either. I'd guess the closer you had the fantech to the source, the more the fan action and venturi would overcome any lift from heat gradient, but thats all just a guess. I'd be curious to see what the building science guys think.DCG Your Neighbor's Contractor LLC
"A wrongdoer is often a man who has left something undone, not always one who has done something."--Marcus Aurelius
I don't think warm air has enough "lift" to overcome mechanical venting. The additional elbows would be more of an issue, slowing down air flow. I try to keep roof penetrations to a minimum, and don't like venting out soffits either, so will go to some length to get a vent out through a sidewall.
Agreed, soffit venting is a big no-no, it allows soffit vents to pull wet air up into the attic. For the same reason though, if the roof is directly above the level of the bath being vented, a wall vent poses similar problems. And yeah, a good fan would most likely let you push the air any way you wanted, but how 'bout one o' them nutones for 14.95? Sounds like this guy is thinking Fantech, they're pretty good, right?DCG Your Neighbor's Contractor LLC
"A wrongdoer is often a man who has left something undone, not always one who has done something."--Marcus Aurelius
I suppose if the wall vent was right below the soffit you could suck moist air up into the roof vents. On my house I ran the vent out the gable end, which I think is ideal, but obviously not always possible.
Fantechs are excellent. The only problems are they are a bit on the pricey side, and they are so quiet it's too easy to leave them running. Their fan/light combo is something special.
I gotta check into the fantech for a place I'm building now. Does the fan justify the price compared to a good panasonic in your opinion? Every bath I've done in the past two years (9 in all) got the four button timer and matching dimmer from leviton. They get good responses in out market, now if they'd only make that timer in black. Are you reading this, Leviton? They want it in black!Let's hope they hear, eh?DCG Your Neighbor's Contractor LLC
"A wrongdoer is often a man who has left something undone, not always one who has done something."--Marcus Aurelius
Put it this way...to my clients, I always talk them into Fantech. For my own house I installed a Panasonic. Depends on your tolerance for noise and how important looks are. And how cheap you are.
We install a lot of Leviton products, but I hadn't seen the timer you're talking about. Is this it http://beverlyhillselectric.stores.yahoo.net/6230m.html? That looks perfect for my house.
Just curious, most people have light-colored walls in their bathroom, why do you want black?
that's the animal, the timer and dimmer match, though the timer's got red led and the dimmer green, not sure why Really nice to have a dimmer that's easy to hit when you don't want full blast light at 3:00am.black? we do quite a bit of metro/urban in seattle. Black w/ stainless covers looks very, very nice. Bold colors and materials like slates and granites go well with the stainless covers and the black looks best in those. easy faucet hardward match too.DCG Your Neighbor's Contractor LLC
"A wrongdoer is often a man who has left something undone, not always one who has done something."--Marcus Aurelius
black? we do quite a bit of metro/urban in seattle. Black w/ stainless covers looks very, very nice. Bold colors and materials like slates and granites go well with the stainless covers and the black looks best in those. easy faucet hardward match too.
Nice. I don't get to do much modern stuff, mostly serene Nantucket/Kennebunkport looking stuff.
I know Seattle is a big city, but have you ever run into Jeff Knudsen (designer/builder)? I worked with him one summer.
I think the soffit thing is relatively bogus. If you block the soffit venting within 2-3 feet of the outlet, that should be sufficient to prevent any significant reentry of the moist air.
People never lie so much as before an election, during a war, or after a hunt. --Otto von Bismarck
I'll agree with that, but how often do you think the soffit gets blocked?
You mean by the insulation guys? ;)
People never lie so much as before an election, during a war, or after a hunt. --Otto von Bismarck