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How to vent a bathroom?

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Joined: Aug 22 2003

We desperately need to add venting (a fan/light/perhaps heater unit) to our bathrooms.

All the ceiling vents I've seen (e.g., we like the panasonic ones for their quietness) seem to need to run ductwork through an attic.

Is there a product that can vent through our wood ceiling/roof?

We could do a wall vent, but the exterior wall is in the shower, so it's not ideal. We could lower the ceiling by 7"-12" so as to be able to install a ceiling fan and run the ductwork out the wall, but our ceiling is only 8', and we really don't want to lose any height (especially in the shower area, which already has a raised floor)

How have people successfully vented their Eichler bathrooms?


Joined: Mar 20 2003

Hi Jessicar-

I put a fan in each of my bathrooms when I replaced my roof with a foam roof.

It was pretty tricky and a bit funky but it works and it's pretty solid. I am very happy with the results.

1) In the hall (main) bath, I replaced the old fan with a Panasonic Whisperlite.

2) In the master bath, there was not fan so I replaced the light with a fan/light combo. Panasonic has one but I choose the Nutone Quiet Test. I bought both at Bayshore Electric in San Carlos (if you live in the Bay area). Both brands were about the same in terms of sound (very quiet at less than 1 sone) but the Nutone had a brighter light.

I used both original electrical lines so we carefully unattached the original fixtures then used this electrical line (on the roof) to hook into the new fans. That way I could use the existing wall on/off switches.

I also switched one on/off light to a 60 minute timer. Ventilation experts recommend running the fan for 60 minutes to properly ventilate the bathroom. Basically, running it only during a bath isn't adequate since there is still alot of humidity left in the bathroom.

It's also necessary to properly size the fan. Since Eichler bathrooms are small, you probably need one of the smaller fans. I believe I have one in the 50 CFM range- the guy at Bayshore looked at me strange since they never usually sell the small ones- who has a smaller bathroom than an Eichler?? You can size the fan properly by checking the Home Ventilating Institute's website at:

If it was any stronger, my kids would complain that is was too cold and breezy during a bath. People don't use fans if they create too much breeze or are too noisy. Right now the smaller one works great for removing the humidity without being uncomfortable. Bathrooms fans are essential to keeping the indoor humidity below 50% in the home- especially for those with 3 or more people in the home.

I ended up putting the fans on the roof and Able Roofing puts a wooden box with a metal vent cap over it. I guess another competing foam roofing company does the same thing. Then the whole thing gets foamed over. It's pretty hard to describe but I have photos if you want to see them. You can email me at lynndrake2001ATyahooDOTcom and I can send them to you.

Good luck, Lynn

Joined: Apr 2 2003

>> I also switched one on/off light to a 60 minute timer.

Lynn, I'm interested in the 60 minute timer you installed. Where did you get it and what does it look like? I have a triple switch plate in the master bath area and would love to put a timer on the bath's light/fan switch.


eichfan at rawbw dot com

Joined: Mar 24 2003

Lynn, I'm interested in the 60 minute timer you installed. Where did you get it and what does it look like? I have a triple switch plate in the master bath area and would love to put a timer on the bath's light/fan switch.

I installed the Decora LE6260 MW on both my bathroom fan switches. I got them at and you can see what it looks like at:

It's fabulous for the fan application, installs pretty easily except for the crowded eichler electrical boxes.


Joined: Mar 20 2003

I purchased the timer at Orchard Supply Hardware. It's a pretty standard timer - all mechanical and a manual turn dial. It ticks faintly. It's about 1.5" x 2.5" and fits into a switchplate and cost about $12.


Joined: May 8 2004


Just checking if there are any updates to techniques or new suggestions on ventilating an Eichler bathroom since this dialog below. Is NewTone 8210 and Whisperlite still the way to go?

We're remodeling the bathroom and want to include ventilation. This bathroom is tiny even by Eichler standards. On the wall, we'd have no more than 7 inches from the top of the new door to the support beam. In as much as we're reluctant to bore through the roof, that may be what we'll have to do.

So any recommendations on the following appreciated:
1) For going through a ceiling and two levels of roofs (including a bitumen roof), what would you recommend?
2) Did I see correctly that some fans have a light / fan combination?
3) Should the fan be hooked up to the light switch or install a separate circuit?

Any success stories appreciated. thanks,

Joined: Apr 10 2006

Hi, For bathroom exhaust fans we installed the Panasonic models through the roof before we had Durafoam install a new roof. They have recommendations on their website for through roof installs, basically you have the contractor make a box that encloses the fan and it just sits on top of the existing roof. When the roofers come they will seal it all up. The pdf for this is here:

And you can see other Durafoam recommendations here:


Joined: May 23 2011

SInce there is no space between the ceiling and the roof for a bracket, it sounds like the only possibility is to build out of the roof with the fan like the others have done. I would get a contractor or roofer who is familiar with Eichler homes or other homes with no attic, to take a look at what they can do. Usually the light/fan vents have two controls for the light and the fan.

Regina - Need help from a San Francisco handyman

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