Min CFM for Bathroom Exhaust
Min CFM for Bathroom Exhaust
(OP)
Hi,
Does ASHRAE 62-XXXX have any values for exhaust from rest rooms in public buildings?
What is the min required from Building code perspective.
I am confused because some codes refer to Area, some to People and some to Number of stalls.
Thanks,
Does ASHRAE 62-XXXX have any values for exhaust from rest rooms in public buildings?
What is the min required from Building code perspective.
I am confused because some codes refer to Area, some to People and some to Number of stalls.
Thanks,





RE: Min CFM for Bathroom Exhaust
I use 10-15 air changes/hr for fan sizing; nobody wants to smell sewage.
RE: Min CFM for Bathroom Exhaust
5 cfm per person plus 0.06 cfm/ft^2
RE: Min CFM for Bathroom Exhaust
Standard Mechanical code was 2 CFM/ square foot of the public bathroom
Take the "V" out of HVAC and you are left with a HAC(k) job.
RE: Min CFM for Bathroom Exhaust
Take the "V" out of HVAC and you are left with a HAC(k) job.
RE: Min CFM for Bathroom Exhaust
RE: Min CFM for Bathroom Exhaust
www.vanderweil.com
RE: Min CFM for Bathroom Exhaust
RE: Min CFM for Bathroom Exhaust
It basically recommends a design criteria of either 2 CFM/SF, 10 ACH, or 100 CFM/water closet and urinal. It then shows some of the codes and their specific requirements, but it further goes on to say the following:
1. For toilet rooms with high fixture densities (stadiums, auditoriums), 75 CFM/water closet & urinal dictates.
2. For toilet rooms with ceiling heights over 12', the 10 ACH dictates.
3. For toilet rooms with ceiling heights 12' and under, the 2 CFM/SF dictates.
4. If toilet rooms are designed for 100 CFM/water closet/urinal, all three major codes and the 10 ACH can be met.
5. If women's and men's are essentially the same size but have different fixture count (typically less in the women's), use the larger CFM for both toilet rooms when using the CFM/fixture method.
Anyway, since it's an easy calc, I usually check all three and pick the one I like depending on the job. My particular local mechancial code calls for the 75 CFM/fixture at public spaces (less for residential).