Hi,
We have a tricky situation. We have a dormitory with apartment-style dorms. There is a common living area/kitchenette with four student bedrooms (with private baths) off a common corridor. The bedrooms and living area/kitchenette meet ASHRAE 62.1-2007 reqs for naturally ventilated spaces.
Question 1: The students eat their meals at a common cafeteria and so the kitchenettes are equipped with an electric hot plate, microwave, and fridge and are used for preparing snacks, coffee, etc. Do we need to provide exhaust for the kitchenette? It is not a true kitchen/will be used sparingly and is part of a space being naturally ventilated.
Question 2: Do we need to provide mechanical exhaust for the bathrooms? Typically in residential applications we do provide mechanical exhaust, but in this case the client would like to omit the exhaust since it is not required by code and the bedrooms are being naturally ventilated.
Thank you for your insight.
Andrew Mitchell, P.E.
PrincipalMitchell Gulledge Engineering, Inc.
LEEDuser Expert
126 thumbs up
October 10, 2013 - 10:56 am
Michael, table 6-4 requires exhaust of 0.30 cfm/sf in Kitchenettes and 25 or 50 cfm for private toilet rooms depending on whether the exhaust is continuous or intermittent. Also, make sure to check the ventilation section (normall Chapter 4) of your state mechanical code, there most likely is a requirement for bathroom exhaust.
Michael Wironen
Ecology and Environment, Inc.20 thumbs up
October 10, 2013 - 11:00 am
Thanks for the response. This project is in Africa, so a lot of typical code requirements (and assumptions) don't apply.
LEED Interpretation 10248 suggests that the kitchenette will not require mechanical exhaust since it is part of a naturally ventilated space. It looks like mechanical exhaust of the bathrooms will definitely be required.
Rudolph Carneiro
HVAC consultantOptimized Systems
26 thumbs up
October 10, 2013 - 12:42 pm
Bathrooms do not need to be mechanically ventilated per the standard. Natural ventilation of bathrooms is acceptable. ASHRAE 62.1-2007 is set up so that it is possible to substitute the exhaust requirements of table 6-4 for natural ventilation. In michaels case however, it seems that mechanical ventilation of bathrooms that dont have operable windows to the outdoors would be required.
Michael Wironen
Ecology and Environment, Inc.20 thumbs up
February 21, 2014 - 3:42 pm
We just got our review comments back. No problems related to the bathroom (we ended up going with mechanical exhaust) or the kitchenettes, but we did get a comment on the corridor connecting the bedrooms to the living/kitchen area. This corridor is open to the main space but is more than 25' from the operable windows. Since it is unoccupiable circulation space within an individual dwelling unit, does it really require fresh air per the requirements of 62.1-2007? I've never been asked to provide this on any previous projects. Thoughts?
Erica Downs
LEED ConsultantThe Green Engineer
254 thumbs up
March 3, 2016 - 5:06 pm
Hi Michael -
Did you ever resolve your hallway/circulation space natural ventilation issues? Our project has a similar situation. If you can share, I'd sure appreciate it!
Thanks.