Does multi-occupancy require multi-service

Status
Not open for further replies.

wire_nut

Member
Location
Indianapolis
I am donating my time and license to a Quaker Meeting House that was 30 years ago a side-by-side duplex house. Now half the structure is a (very small) place of worship and the other half contains two dwelling units for the caretaker etc. The three occupancies share one service and even branch circuits may not respect the boundry between the three occupancies. During renovation is there a code requirement (or a practical reason) to rewire the structure with three separate services? Also if the structure remains with one service what load calculation do I use? Can I calculate the general lighting load for the meeting house at 1 VA/Sq foot as a church and the dwelling units at 3VA/Sq foot? per 220.12 and then combine? Same question for general use receptacles per 220.14. Do I need a meeting with the AHJ or is this kind of mess clearly covered in the NEC?
 

Npstewart

Senior Member
There are only special cases where a separate SERVICE is required, such as in the case of a fire pump. Most times, separate services are frowned upon, and almost always require special permission and labeling. I would however SUGGEST a separate service in this case because a church might require 3 phase power if you have air conditioning systems over 5 ton. SEE SECTION 230.2 (B) multiple services are PERMITTED but it doesn't say REQUIRED, for multiple occupancy. This being said, ive never seen a mixed residential/commercial project that didn't have separate services.

If you are taking residential however, and making it a place of assembly, chances are the wiring will have to be ripped out in the areas where it is considered assembly. You will need to re-wire the assembly area per the NEC, using a wiring method approved for assembly, which means the current romex cable will not be acceptable.

I would DEFINITELY suggest having a meeting with the AHJ, the building may require fire sprinklers, and will definitely require fire walls between EVERY separate occupancy. Also, because you are renovating such a large portion of the building, most of it will be required to be brought up to code. Get them on board ASAP, make them feel like they are apart of the project, it will go a long way in the end.
 

Npstewart

Senior Member
Oh and yes, you would use different load calcs, using 3VA/ft^2 + appliances etc for the residential, and you would use the commercial load calc for the commercial areas.
 

Npstewart

Senior Member
Last, I wouldn't allow any branch circuits from the commercial part to be feeding anything in the residential (or) the other way around. Each occupancy/tenant should have their own panel. If a breaker flipped etc, the person should be allowed to access it at any and all times.. OK im done, back to work.
 

steve66

Senior Member
Location
Illinois
Occupation
Engineer
If your state or location has adopted an energy conservation code, that might require separate meters.

And its always good to have the utility involved when making decisions like this.
 

wire_nut

Member
Location
Indianapolis
Gracias

Gracias

Thank you both for many helpful suggestions! I need to look more closely at the definitions and requirements for places of assembly.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
Thank you both for many helpful suggestions! I need to look more closely at the definitions and requirements for places of assembly.
Check with the AHJ on the classification of the structure. NM may be allowed but places of assembly rooms would need to be wired with MC or emt, etc. The rooms themselves not the entire building would qualify as a place of assembly.

No reason for more than one service as long as it is understood there will be one bill from Poco.
 

wire_nut

Member
Location
Indianapolis
The definition of "Place of Assembly" in 518.1 refers to "...portions of buildings or structures designed or intended for the gathering together of 100 or more persons..." Since this Meeting is usually between 10 and 20 worshippers there may be some wiggle room with the AHJ. But I don't want to assume how the AHJ will see it!
 
Status
Not open for further replies.
Top