[bradesp]

I'm building a beach home with 5 bathrooms, each is 5' wide x 9.5' long by 9' high yielding a minum CFM fan requirement of 57 CFM (for 8 changes per hour).

These showers will likley see heavy use by occupants in the humid summertime. Often there will be 2-3 showers in a row. To avoid excessive build up of humidity, I'd like to size the fan larger than the "minimum".

Is putting a 110 - 150 CFM rated bathroom fan overkill for this requirement or am I right to oversize the ventilation in this application?

Thanks!

bradesp

 

[bradesp]

FYI, the location is halfway between Wilmington, NC and Myrtle Beach, SC right about 1,000 feet from the ocean. Hot and humid in July/August, but actually quite decent the rest of the year.

Also, keep in mind this is a rental / investment property. I'm trying to keep things very simple and cost effective. Where I building there is a complete lack of knowledge surrounding "modern methods". So for example, if ERV did prove to be an outstanding way to remediate moisture in this scenario, you'd have a near impossible time finding a contractor in the area who has a clue about how to deal with things like this. No disrespect to the trades there, it's just VERY old school where I'm building.

 

[bradesp]

So, back to my original post, is doubling up on the 8 changes per hour a smart idea or dumb idea?

Thanks.

 

[bradesp]

Re: Large Size

So, back to my original post, is doubling up on the 8 changes per hour a smart idea or dumb idea?

Should no tbe a real concern to use 110 CFM fan for
additional summertime humidity reduction.
50 CFM more for 10 minutes = 500 CFM total.

Dan, Thanks. I have a choice between a 110cfm fan with 4" duct and a 150cfm fan with a 6" duct. AGain, my goal is to clear the hot, humid air from the showers out of the bathrooms as quickly as possible. The beneifit of the 150cfm fan is that it's actualyl as quiet or more so because of the larger duct size.

Thoughts?

Thanks.

 

[bradesp]

Phil,

Thanks! This is exactly the practical advice I was after.

BTW, do you have a suggestion on the brand/type of timer switch to use?