No Ceiling in Bathrooms

[PatBethea]

I'm doing the HVAC for a bowling alley. I went out with the mechanical contractor one day last week and discovered that the bathrooms are being built without a ceiling. The owner decided he would just build up 8' walls around the bathrooms, but not enclose them. My initial response was, "You can't do that." He said, "Why not?" I never could find a prohibition in the code to building a restroom without a ceiling. If anyone knows of one, please let me know. For the record, this is in FL.

Anyway, I need to reconfigure the exhaust from the restrooms now. Each consists of 7 water closets (and/or urinals). My first thought was to use two roof-mounted fans per restroom (~250 cfm each) and have each fan ducted down to a return grille mounted about 8' AFF. By doing this, I feel confident I'm meeting the "letter of the law", but I'm not so sure I'll meet the intent.

Not mentioned above, but relevant, is that the restrooms are located very near to the snack bar and small dining area. Should I maybe duct to a grille above each water closet/urinal? Increase the amount of air being discharged? Stick with my original idea? Anyone got any thoughts on this?

 

[AbbyNormal]

you do not need a ceiling, just extend the walls to the roof

Take the "V" out of HVAC and you are left with a HAC(k) job.

 

[PatBethea]

They do not plan on extending the walls to the roof. If they would do that, it would be a no-brainer.

 

[KiwiMace]

The airspace from a bathroom cannot be connected to an area used for food preparation. What do you mean by 'near'?

I would also be checking the fire separation part of the code for specifics regarding the two changerooms. I know in theatres there must be a 1hr rated separation between these spaces.

So the mens and womens have only an 8' wall between? In the age of youtube, this is unacceptable. While there remains 10 year old boys, there remains a privacy issue.

 

[IRstuff]

8' wall simply means that the mirrors need a 4' extension. Compared to normal restroom, it's a cakewalk.

TTFN

FAQ731-376

 

[PatBethea]

IRstuff, not sure what you're saying. I assume you're trying to be funny.

Kiwi,

You said, "The airspace from a bathroom cannot be connected to an area used for food preparation." Can you point me to a section in a building code (FL code is modeled on the IBC) where this is stated? How do you define "connected"? I agree with what you are saying, but if it is not a code requirement, I cannot require it. The men's restroom has a wall that will be approximately 8-10' from the snackbar.

No fire wall is required.

To date, neither the building inspector(s) nor the fire marshall have a problem with anything they are doing. I do not believe that any health inspectors have been involved yet.

 

[KiwiMace]

1210.5 interior environment.

 

[PatBethea]

Thank you. Now I guess it is all a matter of interpretation. Technically it does not open directly into the food prep area. I *know* that will be the owner's argument.

Assuming no officials enforce a change, have you got any advice with how to proceed?

 

[KiwiMace]

I think your exhaust system should pick up over the WC's and UR's as you would do if you had a ceiling.

You haven't mentioned make up air, heating or cooling. You need to arrange your supply and exhaust registers to avoid short-circuiting and get some meaningful turnover going.

 

[MintJulep]

Ten feet from the snack bar?

There are frequently auditory emissions associated with the biological process that might cut down on snack bar sales.

 

[willard3]

You are the Engineer: tell them that there will be an operable exhaust system in the enclosed bathroom or you won't stamp the drawings.

We all know what is proposed by the contractor and owner is not best practice.

 

[Wareagl487]

Not installing walls to deck or a ceiling will not meet section 918.6 of the 2006 IMC which states:

918.6 Outdoor or return air for a forced air heating system shall not be taken from the following locations:

5 A closet, bathroom, kitchen, garage, mechanical room, boiler room or furnace room.

Without either walls to the deck and/or a ceiling, you can not guarantee the air introduced will not mix with return air of the system IMO.

I find it surprising the code does not address privacy issues in requiring either wall to the deck or non-accessible ceilings to be installed.

Andy W.

 

[AbbyNormal]

Probably the code does not address it because no one is dumb enough to want to have a bathroom without a ceiling.

They sell Mexican food at the snack bar?

Take the "V" out of HVAC and you are left with a HAC(k) job.

 

[PatBethea]

Abby, that's the conclusion that some contractor friends and I all arrived at.

 

[kdxbob]

FBC 426.3.2.2 Public bathrooms shall be completely enclosed...