# Vestibule not Required in SPACE Less Than 3000 Square Feet



## nitramnaed (Apr 11, 2016)

Quoting from the 2015 IECC about vestibules:

"C402.5.7 Vestibules. Building entrances shall be protected

with an enclosed vestibule, with all doors opening into and out

of the vestibule equipped with self-closing devices. Vestibules

shall be designed so that in passing through the vestibule

it is not necessary for the interior and exterior doors to

open at the same time. The installation of one or more

revolving doors in the building entrance shall not eliminate

the requirement that a vestibule be provided on any doors

adjacent to revolving doors.

 Exceptions: Vestibules are not required for the following:

1. Buildings in Climate Zones 1 and 2.

2. Doors not intended to be used by the public,

such as doors to mechanical or electrical equipment

rooms, or intended solely for employee use.

3. Doors opening directly from a sleeping unit or

dwelling unit.

4. Doors that open directly from a space less than

3,000 square feet (298 m2) in area.

5. Revolving doors.

6. Doors that have an air curtain with a velocity of

not less than 6.56 feet per second (2 m/s) at the

floor that have been tested in accordance with

ANSI/AMCA 220 and installed in accordance

with the manufacturer’s instructions. Manual or

automatic controls shall be provided that will

operate the air curtain with the opening and closing

of the door. Air curtains and their controls

shall comply with Section C408.2.3"

My question is on the word "SPACE".  I've always interpreted this to mean the room you are entering.  I have a 5000 square foot retail space thats divided up into different rooms (Office, storage, toilet rooms, etc) making the display area less than 3000 square feet.  The AHJ is saying that space means the entire leased premise, I disagree.

Comments?

Thanks!


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## steveray (Apr 11, 2016)

I agree with your interpretation.


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## TJacobs (Apr 11, 2016)

I agree with your interpretation.  I do not include areas with a closable door.


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## JBI (Apr 11, 2016)

Since the requirement is based on a loss of 'conditioned air' from the conditioned space to the exterior of the space, I too agree with you (though 'interpretation' is not up to an applicant or DPR, so you actually have an 'opinion' that I agree with). Understanding why a code section exists is instrumental in understanding how to apply the provision.


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## nitramnaed (Apr 11, 2016)

Building Official has decided to back off.  He now agrees that it should be the room not the leased premise.  :applause:

Thank you for your feedback!


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## Keystone (Apr 11, 2016)

Glad to read the BO changed his/her thought process, it's important to remember we're all human and make mistakes, do you know what prompted the change?


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## nitramnaed (Apr 12, 2016)

Misinterpreted the original submittal which had the client involved.  I think it was just mentioned in passing and the client freaked out.  Once we had further discussions we were all on the same page.


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## Keystone (Apr 12, 2016)

Ahhhh. The all to common, to many hands in the cookie jar. I personally make it an unwritten policy to avoid contact with multiple persons regarding a job. The misunderstanding, lack of knowledge or motives can and has created a circus at times.


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## ADAguy (Oct 3, 2016)

Use of an experienced "expediter" can often prevent just such issues, but not always.


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