Wall Saturated

[nailer]

i hope someone call provide some advice. my shower stall(glass sliding doors) is just inside entrace of bathroom on right side. the entry area is only 3 feet wide(to left of shower) until you get to sink area and then the bathroom opens up 12 feet wide with additional 8 feet in length. There is a large jacuzzi tub on the left side of bathroom. my problem is when i shower the walls to the left of the shower become saturated with moisture. in addition the ceiling has dark patch about 6 inches beginning where walls meet ceiling. even after walls are dry you can still see the staining from the moisture. when we moved into house i did not see any evidence of moisture issues from showering on walls..we painted the bathroom a year after moving in. the bathroom did not have an exhaust fan when we moved in so i installed one when we painted the bathroom. it is rated at 110cfm and is in the middle of bathoom about a foot after emerging from entry area left of sink. the top of the shower doors have an opening about 8 inches and the top of the shower overhang is about 1.5 lower then the bathroom ceiling.
My first thought is that the fan is pulling the moisture out of shower and causing it to gather and condense in the entry area thinking exhaust fan is too far from shower. i tried several times now showering without exhaust fan on as it was before we moved in thinking that it would just collect on shower ceiling but it stills results in same situation on walls and ceiling. i am thinking of purchasing a new fan with about 300cfm in the inline style having two inputs and putting one directly outside of shower and other where existing fan is located. i will adjust so most of exhaust will be directed towards inlet outside of shower...thanks for any input on this issue

[Redwood]

Where does this exhaust fan exhaust to?
I usually shoot for 1/4 of the volume of the room for fan sizing.

[nailer]

Where does this exhaust fan exhaust to?
I usually shoot for 1/4 of the volume of the room for fan sizing.

vented horizontally in attic to soffit. its insulated as well

[Redwood]

Okay thats a good thing!
What is the volume of the room?

[nailer]

Okay thats a good thing!
What is the volume of the room?

ceiling is 8'..i would estimate volume at 850 square feet..."X" marks current fan location and problem areas arewall to left of shower(staining almost half down wall) and ceiling has approx 6 inch dark band around perimeter outside of shower area.

11.5'
---------------------------------
- -
- -
6' - - 8'
- -
- -
-------------- X -
6' - -
- -------
- -
6' - -shower
- -
- -

door

[nailer]

not sure if my drawing came through but think 3 feet corridor 6 feet long leads into 11.5 feet by 6 feet rectanglar space

ceiling is 8'..i would estimate volume at 850 square feet..."X" marks current fan location and problem areas arewall to left of shower(staining almost half down wall) and ceiling has approx 6 inch dark band around perimeter outside of shower area.

11.5'
---------------------------------
- -
- -
6' - - 8'
- -
- -
-------------- X -
6' - -
- -------
- -
6' - -shower
- -
- -

door

[Redwood]

I'm not sure what all that stuff is that you wrote but if the room is 850 cu. feet then I would go with a 200 - 225 CFM ballpark.

Check out this in-line Panasonic...
240 CFM in line Panasonic
Its quiet and moves a bunch of air.
Another consideration is how is air getting into the room?
You are taking it out how does it get in?

[nailer]

I'm not sure what all that stuff is that you wrote but if the room is 850 cu. feet then I would go with a 200 - 225 CFM ballpark.

Check out this in-line Panasonic...
240 CFM in line Panasonic
Its quiet and moves a bunch of air.
Another consideration is how is air getting into the room?
You are taking it out how does it get in?

i was actually looking at that model but the next stronger one with 300+ CFM and putting two outlets in one outside of shower and other above sink area.

[Redwood]

I just wanted to make sure you were looking at the Panasonic line...
I like them!
With problems like yours it may be wise to take the Tim Allen approach.
My main concern though is make up air.
With that much leaving the room you need to let air in also.
That may also be part of your problem now.
Try leaving the door open a crack next time you shower.

[nailer]

I just wanted to make sure you were looking at the Panasonic line...
I like them!
With problems like yours it may be wise to take the Tim Allen approach.
My main concern though is make up air.
With that much leaving the room you need to let air in also.
That may also be part of your problem now.
Try leaving the door open a crack next time you shower.

Yes i went through severals trials door open, door closed, fan on fan closed..still got lots of moisture build up..

[Redwood]

Well you existing fan is 1/2 the size of what you need so you should see quite an improvement.

[nailer]

Well you existing fan is 1/2 the size of what you need so you shoukl see quite an improvement.

yes i do not know what i was thinking when i chose that fan although now that i think about it, it had the most CFM with a heater etc....thank you for all you comments and assistance..

[jadnashua]

One thing to consider, and I think it was mentioned, is that the air you are dumping outside requires makeup air from somewhere - if you don't have a controlled place for it to come from, it will draw through cracks and poorly sealed places all over the house. A large exhaust fan means reconditioning a lot of air you've already paid for to condition, so limiting to what is needed is critical for economy.

Some, but not all, heat recovery ventilators will respond to those barrometric pressure changes and move makeup air into the house without losing all of the energy. To minimize the conditioned air loss, you may want to consider a humidistat on the fan, then it will only run when required, and limit the energy loss.