Bathroom Vents

Bathroom vents are important for a lot of reasons but mostly to remove moistue when bathing.  They should be quiet, efficient for the room size, and strategically placed.  They should be vented to code and sealed off with no leaks from the unit to the exterior vent.  

I'm sure you know where this is going.  So my builder thought it would be a great idea to buy a bunch of - might I add, the WORST vent on the market - a 50 cfm (cubic feet per minute) with a noise level of 4.0 and place them in all the bathrooms regardless of the  room size or the ceiling height.  Couple that with the fact that the installer thought it would be good idea to shove a box in my ceiling and tape it in place and not even bother to fully hook up the exhaust duct work to the unit and if he did, it was never taped in place and leaked which basically sent the steam between my ceiling rafters.  I'm not sure if a 3" duct to the roof met code a few years ago but if it didn't, it's what he used anyway.

So I bought wonderful super quiet 50/80/100 cfm with a noise level of .9 when using the 100 cfm setting.  You have to listen to know that it's on in one application because it has a 4" duct from my unit to the roof jack.  The day we replaced our master bathroom vent I immediately knew I was buying 5 more.  I would've loved to have a heater/vents in all baths with tubs because I feel that when bathing on a cool morning when later in the day temperatures are going to warm up, it prevents the heat from becoming necessary.  At the VERY LEAST that should be a building standard for a mster bathroom, but nope, this builder only installed the cheapest vent on the market and located it on the vault furthest away from the shower.  I couldn't have installed a vent heater if I wanted and I did want to because there was no access.  So imagine a vaulted huge master bathroom with one tiny 50 com vent that did absolutely nothing.  It should've have failed inspection based on location alone.

Now that all the vents were replaced and properly taped for a good seal to the actual duct work using a 4" to 3" interface, the smaller rooms are noisier than my master bath probably on account of not having 4" duct work.  But in all they are quieter and do the job.  Any location where I have a shower, I used to 100 cfm setting but may back to down to 80 instead for a quieter experience.  

In researching duct diameter, use 4" since 3" is a waste of time and material and means you have a cheap vent.  Also, if you ever want to update anything, the new models are not 3" and you may have to replace all the duct work to the roof when you enter into renovation projects requiring permits - a very costly requirement.  Not to mention, my first arguement that is you want steam removed from you bathroom so get a decent model and use the 4" hose right off the bat.