California / Bathroom Exhaust

[Joe Reilly]

In regards the bathroom exhaust fans, Califoirnia Residential Code from 2013 state

"R303.3.1 Bathroom exhaust fans. Each bathroom containing a bathtub, shower or tub/shower combination shall be mechanically ventilated for purposes of humidity control in accordance with the California Mechanical Code, Chapter 4; and the California Green Building Standards Code, Chapter 4, Division 4.5.Note: Window operation is not a permissible method of providing bathroom exhaustfor humidity control."

The root of my question would be is a 'toilet only room', considered a part of bathroom when it comes to fans & windows ?


Using these guidelines, please help clarify these scenarios.

Let's assume this house was built in 2017.

An Exhaust fan is in the toilet room (which has its own door) and does not have a tub, nor shower in it; and the Shower / Tub area only has a window. Would the fan in this area be consider valid regarding the code ?

TIA

[Jerry Peck]

Only if you removed the toilet room door, and then make sure that the fan meets the cfm requirements for the size of the entire bathroom.

My guess would be that it is likely a cheap exhaust fan in the toilet room and insufficient for the bathroom size.

Just my guess.

[Gunnar Alquist]

Joe,

I agree with Jerry, but it would also depend on the local inspector. I suspect that some might see the fan and call it good, even though it is clearly in a separate room.

Like Jerry said, fans in toilet rooms typically do not move enough air to exhaust enough air.

[Joe Reilly]

Only if you removed the toilet room door, and then make sure that the fan meets the cfm requirements for the size of the entire bathroom.

My guess would be that it is likely a cheap exhaust fan in the toilet room and insufficient for the bathroom size.

Just my guess.


Thank you for the reply. That was my though, but to get any agent to believe you and think you are not being super pickey, well thats another story in itself.

- - - Updated - - -


Joe,

I agree with Jerry, but it would also depend on the local inspector. I suspect that some might see the fan and call it good, even though it is clearly in a separate room.

Like Jerry said, fans in toilet rooms typically do not move enough air to exhaust enough air.


Thank Gunnar, between you and Jerry I can always get a good answer.

[Jerry Peck]

Only if you removed the toilet room door ...

I was going to add (and guess I now am adding it) :) ... not just "remove the door" as some jerks will try to do, but to remove the hinges and jambs too. :D

I know you would already know that, but I was thinking of adding it because I would in my reports.

Door? There ain't no door there! (Yeah, sure, but you left it sitting against the wall next to the door opening. I may have been born at night, but I wasn't born last night.)

We've all seen that happen.

[ROBERT YOUNG]

Joe, would be a water closet or toilet room?

[Joe Reilly]

Joe, would be a water closet or toilet room?

The current fan is in a toilet room.

(Toilet only in the room)

[Gunnar Alquist]

Joe, would be a water closet or toilet room?

Robert,

Isn't a water closet another name for toilet?

[ROBERT YOUNG]

Robert,

Isn't a water closet another name for toilet?

Morning, Gunner.
I am use to referring the term water closet as a room with just a toilet or back in the day, a commode.

[ROBERT YOUNG]

The current fan is in a toilet room.

(Toilet only in the room)
Moring, Joe. Hope this post finds you well.
Sorry for the delayed response. I beg your pardon.
As well, I misread you post.
A toilet room is part of the bathroom when it is within the same space.
In my neck of the woods there are many century homes. The toilet room is separate room with a separate entrance door off the hallway. It is not incorporated within the bathroom space.
If the toilet room is in the bathroom. It gives the occupant more privacy.

The toiletroom has mechical ventilation and the bathroom has passive ventilation, a window I would not worry about it unless there is a buildup of condesation.
Leave the toilet room door open, except when in use, which I doubt is often. Just insure the toilet room door is open when the occuppent/s leave the bathroom.
As well, run the mechanical ventilation for the desired time required to exhaust damp moist air to the exterior which could be as long as 60 minutes.
PS: I would not open the window unless needed. Always remember to close the bathroom window afterwards.

[Jerry Peck]

A toilet room is part of the bathroom when it is within the same space.

Robert, a toilet room is separate from the bathroom are, just like the bathroom is separate from the living space adjacent to it.

Doors separate both from the other.

Yes, a toilet room is required to have mechanical ventilation. And, yes, a bathroom also requires mechanical ventilation.

Place the toilet (aka watercloset) within the bathroom area, and there is not "toilet room", it is part of the "bathroom". Place the toilet in its own closed off space with a door and it becomes a "toilet room" ... whether or not it is located within a bathroom area or not.