Accessory Use--Does it count towards your plumbing fixture count?

[Juliet]

A little confusion here about Accessory use and the plumbing fixture count--does accessory use areas count towards the plumbing fixture count?

 

[Paul Sweet]

Accessory uses do count. You have to count the fixtures required for each use then add them up. I've always been able to add fractional numbers of fixtures for each use, then round up to the next integer for the sum.

 

[Tim Mailloux]

I've always been able to add fractional numbers of fixtures for each use, then round up to the next integer for the sum.

the IPC code commentary actually shows this approach in a nice calculation format that I have implimented as an office standard.

 

[Yikes]

Juliet, I'd say it depends on the accessory use.

For example, we often design R-2 apartment complexes with A-3 recreation / community rooms for the exclusive use of residents to have their own gatherings. These rooms are accessory to the dwelling units.
At most we have 1 or 2 single-accommodation toilet rooms serving these community spaces, just for convenience.

The idea here is that if a resident needs to use the restroom, they all have the ability to return to their own nearby apartment. In practice, most residents will likely use the bathroom in their own apartment prior to visiting the community room.

In this situation, the AHJ utilizes their authority under (California/Uniform Plumbing Code) Table 422 footnote 7, and sections 1.8.7 and 301.3 to assign the community spaces an occupant load of zero for purposes of determining minimum # of fixtures.
I've been doing this for years, and have never had an AHJ require toilet rooms for community spaces intended for private use.

If, on the other hand, the apartment complex allowed the community space to be rented out to the general public, then it would be totally appropriate to provide the A-3 occupancy with its own restroom facilities.

 

[YongMNLad]

Juliet, I'd say it depends on the accessory use.

For example, we often design R-2 apartment complexes with A-3 recreation / community rooms for the exclusive use of residents to have their own gatherings. These rooms are accessory to the dwelling units.
At most we have 1 or 2 single-accommodation toilet rooms serving these community spaces, just for convenience.

The idea here is that if a resident needs to use the restroom, they all have the ability to return to their own nearby apartment. In practice, most residents will likely use the bathroom in their own apartment prior to visiting the community room.

In this situation, the AHJ utilizes their authority under (California/Uniform Plumbing Code) Table 422 footnote 7, and sections 1.8.7 and 301.3 to assign the community spaces an occupant load of zero for purposes of determining minimum # of fixtures.
I've been doing this for years, and have never had an AHJ require toilet rooms for community spaces intended for private use.

If, on the other hand, the apartment complex allowed the community space to be rented out to the general public, then it would be totally appropriate to provide the A-3 occupancy with its own restroom facilities.

Yikes, I appreciate your common sense approach to this. Curious if you would expect the same approach of an office building with small meeting spaces. If the spaces are less than 750 sf and say 48 occupants, should the 48 occupants be included in the plumbing fixture calculation? Or could the same consideration be applied where the meeting space occupants would be the same as the offices?

 

[Tim Mailloux]

Yikes, I appreciate your common sense approach to this. Curious if you would expect the same approach of an office building with small meeting spaces. If the spaces are less than 750 sf and say 48 occupants, should the 48 occupants be included in the plumbing fixture calculation? Or could the same consideration be applied where the meeting space occupants would be the same as the offices?

what about visitors / client coming into office for meetings? The IBC does not recognize the concept non-simultanious use as far as I know.

 

[Yikes]

Yikes, I appreciate your common sense approach to this. Curious if you would expect the same approach of an office building with small meeting spaces. If the spaces are less than 750 sf and say 48 occupants, should the 48 occupants be included in the plumbing fixture calculation? Or could the same consideration be applied where the meeting space occupants would be the same as the offices?

At our own office design, we did as Tim suggested in post #6 - - we counted the conference room occupants s being in addition to the office space occupants. As Tim said, we have visitors that come to our office for presentations.
That said, I could see someone making the case that a conference room woudl be for internal use only, so as not to double-count the occupant load.

Years ago I had another project, a youth center at a church. Their ministry concept is that they had a large assembly room where all the youth would gather to hear the main speaker, and then they would break off into "small groups" of about 15 kids + mentors and go into surrounding rooms so they could discuss their thoughts in private. Those small rooms surrounded the perimeter of the main assembly room, and they could only be accessed through the main assembly room. In other words, it was extremely unlikely that the breakout rooms and main room would be used simultaneously by different people.

In that scenario, solely for purposes of plumbing fixture count the AHJ agreed to base the # of occupants on just the occupant load of the main assembly room, not the breakout rooms. The main room was also based on standing occupancy, while the breakout rooms would have been tables and chairs.
There's never been a line at the restrooms since it was built.

 

[steveray]

Yep.....and this is why I "let them" use the gross number for fixture count in an office building lets say, but when it comes to egress stuff the conference rooms need to have been figured at 15 net....