Bathroom fan replacement (v. quieter + more CFM)

[Stereodude]

Has anyone replaced a bathroom exhaust/ventilation fan with a quieter unit?

I'm nearly certain that the unit in my master bathroom is undersized. I can't find a CFM rating on it anywhere, but it's small (compared to the units with a proper CFM rating) and quite noisy. From the calculation based on the CFM of the bathroom I should have ~120CFM. I'm guessing the one there is maybe 70CFM. After a trip into the attic this morning I was able to determine that I have 4" flex duct. The quiet 130CFM+ models generally are intended for 6" ducting and the reviews say they get noisier if you use a 6" to 4" adapter. I don't want to mess with trying to put in a 6" outlet in the side of the house and have to deal with fixing/messing with the siding, so I'm pretty sure I will stay with the 4" ducting.

This 110CFM Delta Breez unit caught my eye. It's for 4" duct, should have a decent CFM increase from the existing fan, is quiet, not too expensive, & pretty power efficient. It is physically larger (there's no free lunch). It looks to be 4" taller than the existing fan housing as well as being longer and wider. I will need to enlarge the hole in the drywall, but I can handle that. Of course the existing fan is located pretty close to the edge of the roof and there's not a lot of height above it so working on it in the attic will not be ideal, but it looks like most of a retrofit install is done from below.

 

[Stereodude]

So I looked closer at the existing fan. It's rated for 50CFM at a noise level of 4 sones. No wonder I'm unhappy with it.

 

[DrunkenBastard]

My past research indicated Panasonic units were best for noise levels. I've got some builder grade shitboxes that are ridiculously loud. Will be my next house upgrade.

 

[Stereodude]

My past research indicated Panasonic units were best for noise levels. I've got some builder grade shitboxes that are ridiculously loud. Will be my next house upgrade.

There are a number of companies claiming to have .3 sones bathroom fans now. I think Panasonic was the first though.

 

[ddrueding]

I had an old, undersized unit that was an unusual size that I didn't want to mess with. I bought an in-line unit that I mounted to a rafter and wired it in parallel with the existing unit. Easy to do and very effective.

 

[Handruin]

Oddly none of the bathrooms in my house have fans. My house was built in 1985 which I would have thought that fans were a thing in the 80's but I guess not for this builder.

 

[Stereodude]

Oddly none of the bathrooms in my house have fans. My house was built in 1985 which I would have thought that fans were a thing in the 80's but I guess not for this builder.

You don't have any issues with moisture build up from the shower?

 

[Handruin]

No, nothing that would promote mold, mildew, etc. There are some days when showering where the bathroom does get really humid/foggy but if the HVAC turns on the room clears out pretty quick. There is a vent port in the ceiling for the forced air but it doesn't vent outside. When I get to renovating my bathrooms I may look into adding a bathroom vent.

 

[LunarMist]

The vents are where the cameras are hidden.

 

[Stereodude]

The vents are where the cameras are hidden.

Is that what you've done at your house to spy on people in the bathroom?

 

[LunarMist]

No. I have an old, noisy fan.

 

[Stereodude]

No. I have an old, noisy fan.

That precludes it from having a spy camera?

 

[LunarMist]

That precludes it from having a spy camera?

Why in world would anyone do that? They would spy on me in public or some location where I'm doing something of interest, not that there would be much. In the bathroom, I'm just having a typical toilette.

 

[Stereodude]

Why in world would anyone do that? They would spy on me in public or some location where I'm doing something of interest, not that there would be much. In the bathroom, I'm just having a typical toilette.

I don't know. You brought it up. I figured you were posting from experience.

 

[Chewy509]

@sd, I think LM was implying he was installing the hidden cams there for his own use...

 

[LunarMist]

No. I did not mean to imply that I had one.
I replied in the wong dimension.

 

[Will Rickards]

lol

 

[Stereodude]

I bought two of the 110CFM Delta Signature fans. I'm going to change one in another upstairs bathroom also. I haven't had any desire to spend time in a hot attic installing them just yet so they're sitting in boxes for now.

 

[Newtun]

Let us know how the cameras are working.

 

[Stereodude]

Let us know how the cameras are working.

Will do. I've got to get them into the other dimension first though.

 

[jtr1962]

Oddly none of the bathrooms in my house have fans. My house was built in 1985 which I would have thought that fans were a thing in the 80's but I guess not for this builder.

We only have one bathroom and it doesn't have a fan. I always thought fans were a thing if you had a windowless bathroom. We have a bathroom window, and if it gets , we can open it and turn on the whole house attic fan.

 

[DrunkenBastard]

I think the fan is primarily for moisture control from a shower/bath than for smells. To prevent mildew/mold. In a NY winter I wouldn't be opening a window to vent, cost of propane is high enough as is.

 

[LunarMist]

Will do. I've got to get them into the other dimension first though.

I meant it was in the wrong thread. Presumably the fan only fits in one orientation since only the four normal dimensions apply, unlike some situations that require projections into more.

I have multi-toilets and can leave one with it's fan on for a while and use the other.

 

[Clocker]

I know this is late, but in case anyone is interested in a fan, I looked at a ton of them before I settled on replacing my bathroom fan (that was a rattle trap and died) with this Panasonic model. I'm really happy with it. Much much better than the Broan fan that it replaced.

https://www.lowes.com/pd/Panasonic-0-8-Sone-110-CFM-white-Bathroom-Fan-ENERGY-STAR/1000616105