Multiple Occupancy

[augie47]

This is elementary but suddenly I've had a brain cloud......
Existing building with UG service and loadcenter located inside the building.
An addition is added to the building with only a 2 hr firewall separating the two tenants,.
230.40 allows the loadcenter for the second tenant to be located in that tenant space.
Is there any provision that allows a separate UG service to the added space ??

 

[Elect117]

Two "separate" tenet spaces implies two services to me.


1) No wiring between the two separate spaces.
2) Utility is okay with putting in the second service. Might require the second building have a separate address.
3) Each tenet has access to their respective main.

 

[augie47]

I;m having a difficult time justifying that under 230.2 as, with no firewall, it is considered one building.
I can justify multiple service conductors to each tenant but not not more than one actual service.

 

[Elect117]

230.2(B)(1) and 230.3.

I would humbly disagree. I think you have plenty of leg to stand on to call for a second service. The building dept. or utility might instead ask for a multimeter gear or similar style but unless they do, I think you are good.

The NECs definition just requires firewalls be present to call the addition a building.

 

[jaggedben]

How would a 2hr firewall not be a firewall?

 

[augie47]

How would a 2hr firewall not be a firewall?

Our building inspection department does not consider a structure to be a separate "building" unless separated by a 4 hour fire wall,
They consider 2 hr to be a tenant separation wall.

 

[electrofelon]

230.2(B)(1) is kinda strange. I would find it extremely rare for there to be "no available
space for service equipment accessible to all occupants". Seems there is an implication there that the service equipment is inside, which would be much more plausible for there not to be common space, but it doesn't say inside, and is there really no rom outside? And then there is the one service 230.40 ex #1 option where the service disconnects can be in each respective unit and not grouped, so I would have a real hard time as an inspector granting special permission for that one.

 

[jaggedben]

Our building inspection department does not consider a structure to be a separate "building" unless separated by a 4 hour fire wall,
They consider 2 hr to be a tenant separation wall.

You mean for other codes' use of the word building? Or specifically for the NEC?

Regardless, I think the NEC actually gives them the leeway to have that interpretation, tbh. The NEC definition is an embarrassment, it makes no sensible distinction between a building and a structure.

 

[electrofelon]

You mean for other codes' use of the word building? Or specifically for the NEC?

Regardless, I think the NEC actually gives them the leeway to have that interpretation, tbh. The NEC definition is an embarrassment, it makes no sensible distinction between a building and a structure.

I find a similar gray area with the term "occupancy". I have had some inspectors simply consider a tenant space an occupancy, but a given jurisdiction might have a very specific definition, and a tenant space is often not an occupancy in these places.

 

[jaggedben]

I find a similar gray area with the term "occupancy". I have had some inspectors simply consider a tenant space an occupancy, but a given jurisdiction might have a very specific definition, and a tenant space is often not an occupancy in these places.

Occupancies are extensively defined and dealt with by lots of other codes. I think it makes sense for the NEC to essentially defer on that, so that it can be understood consistently with those codes. Or at least, consistently within any given jurisdiction. I think a partially similar approach would make sense for 'building'.