Existing building, split into 2 occupancies. Second service permitted?

[Sparky2791]

We have a client who owns a warehouse building with a single 3000A service fed from a pad mounted transfomer. Metering is in the switchboard by way of a utility company metering compartment.

The client is splitting the building into 2 separate tenants and wants to feed the new tenant space with a separately metered service.

Working through the details of this if permitted and requirements.

The existing service would remain as is.

The ‘second’ service would be fed from the same utility transfomer with a new set of service entrance conductors. Feeds would come from this utility transfomer to an outdoor pad mounted metering compartment and feed into the building landing on the new service entrance disconnect at a new location.

Is this permitted by 230.2 provided there is a fire wall between the 2 spaces making each space its own ‘building’ as per the definition of a building.

Is that the only way this would be allowed?


Thanks for any replies!

 

[electrofelon]

We have a client who owns a warehouse building with a single 3000A service fed from a pad mounted transfomer. Metering is in the switchboard by way of a utility company metering compartment.

The client is splitting the building into 2 separate tenants and wants to feed the new tenant space with a separately metered service.

Working through the details of this if permitted and requirements.

The existing service would remain as is.

The ‘second’ service would be fed from the same utility transfomer with a new set of service entrance conductors. Feeds would come from this utility transfomer to an outdoor pad mounted metering compartment and feed into the building landing on the new service entrance disconnect at a new location.

Is this permitted by 230.2 provided there is a fire wall between the 2 spaces making each space its own ‘building’ as per the definition of a building.

Is that the only way this would be allowed?


Thanks for any replies!

It seems your options are 230.2(B) or (C) and 230.40 exception #1 (which would still be one service).

 

[electrofelon]

And just to clarify, if this were legally two buildings then there would be no need to apply any code section to justify it. 230.2 would be used if it was legally considered only one building.

 

[Sparky2791]

And just to clarify, if this were legally two buildings then there would be no need to apply any code section to justify it. 230.2 would be used if it was legally considered only one building.

In my case one building being split into 2 tenants so to meet the definition of a building and comply with 230.40 exception #1 the fire wall would be required between the spaces.

For 230.2 (B) seems if AHJ allows the 2 services the fire wall would not be required.

 

[Sparky2791]

It seems your options are 230.2(B) or (C) and 230.40 exception #1 (which would still be one service).

Well, after reading 230.40 exception no. 1 over a few times it seems that is exactly the exception to apply in my case and no fire wall would be required or special permission either

 

[electrofelon]

In my case one building being split into 2 tenants so to meet the definition of a building and comply with 230.40 exception #1 the fire wall would be required between the spaces.

Not sure what you mean by "meet the definition of a building". 230.40 exception #1 is for one building. At issue would be how your building department defines an "occupancy"

For 230.2 (B) seems if AHJ allows the 2 services the fire wall would not be required.

I agree

 

[electrofelon]

Well, after reading 230.40 exception no. 1 over a few times it seems that is exactly the exception to apply in my case and no fire wall would be required or special permission either

Just to emphasize what I said in post number 6, the NEC does not define "occupancy".. some areas I've seen it loosely interpreted just as a "tenant space", where in others it is a very specific thing involving firewalls and even potentially in to zoning issues.

 

[augie47]

In our area a second service would be allowed under 230.2(C)

 

[Sparky2791]

Not sure what you mean by "meet the definition of a building". 230.40 exception #1 is for one building. At issue would be how your building department defines an "occupancy"

Read the NEC's definition of a building. 'A structure that stands alone or that is separated from adjoining structures by fire walls'

230.2 starts with 'A building or other structure........ If I have a single building with 4 walls only one service permitted but if I build a fire wall down the middle of the building it can now be considered 2 buildings (per the definition of a building) so a service for each 'building' permitted or in this case a service to each tenants space.
Do you have the NEC handbook 2017? Look at Exhibit 230.6 see reference to fire walls in the exhibit. That exhibit basically mimics what we are looking to do but onlt for 2 tenants.

However,
The building is served by one pad mounted transformer like Exhibit 230.6 . If we pull another set of ungrounded service conductors from the utility transfomer and feed the new tenant space at a new location. Per 230.40 exception no. 1 it seems this is permitted without the fire wall provided you include the proper signage required by 230.2 (E)


Thoughts?

 

[Sparky2791]

In our area a second service would be allowed under 230.2(C)

Would not apply in my case other that 230 2 (c) 3. but would need to get the special permission. 1. & 2. do not apply. Capacity is fine and voltage is 3 phase. I had an inspector argue with me and of course got his way (when don't they) on this section of the (NEC 230 in general) when it cam to adding a service for EVC's at a Honda Dealership. 'That was fun' said no one ever who argued with an electrical inspector about the NEC.

 

[augie47]

Apparently our AHJ is more lenient. If we have a structure with a 3,000 amp service they don't question the existing load but allow a 2nd seriv based on the "2,000" in 230.2(c),. In addition if we are allowed a 2nd service IF the existing service is 500 ft away based on 230.2(B)(2).

 

[electrofelon]

Read the NEC's definition of a building. 'A structure that stands alone or that is separated from adjoining structures by fire walls'

230.2 starts with 'A building or other structure........ If I have a single building with 4 walls only one service permitted but if I build a fire wall down the middle of the building it can now be considered 2 buildings (per the definition of a building) so a service for each 'building' permitted or in this case a service to each tenants space.

Absolutely, no disagreement there. In post #4 you said, "meet the definition of a building AND comply with 230.40 exception #1...." I guess I just found that confusing as to use 230.40 ex #1 you don't need separate buildings. You may need firewalls depending on your building department's definition of occupancy.

However,
The building is served by one pad mounted transformer like Exhibit 230.6 . If we pull another set of ungrounded service conductors from the utility transfomer and feed the new tenant space at a new location. Per 230.40 exception no. 1 it seems this is permitted without the fire wall provided you include the proper signage required by 230.2 (E)


Thoughts?

Yeah but same answer as above, might depend on your building departments definition of what constitutes an occupancy and any requirements for such.

 

[electrofelon]

Apparently our AHJ is more lenient. If we have a structure with a 3,000 amp service they don't question the existing load but allow a 2nd seriv based on the "2,000" in 230.2(c),. In addition if we are allowed a 2nd service IF the existing service is 500 ft away based on 230.2(B)(2).

Would not apply in my case ........ Capacity is fine

Interesting approach I never considered calling capacity a load calc versus going off the size of the service. I have always thought of it the way Augie and Augie's AHJ thinks about it.

 

[brantmacga]

I had a similar conversation this week with ahj in my town. What I was told is that a rated wall was not required, but if it isn’t a rated wall, I would need to group the services. If it is a 2hr rated wall, the services could be split. They have some building size requirements that determine whether a rated wall is required. The structure we were discussing is 10,000 sq/ft, and rated walls are not required. I can’t remember if the threshold was 10k or 12k sq/ft, but over that size would require sprinklers and rated walls between the tenants. It’s worth a call to your ahj to discuss building code requirements.


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[ggunn]

One thing to consider is the added load on the service conductors and transformer when you add a second kitchen, water heater, HVAC system, etc. to them.

 

[Sparky2791]

One thing to consider is the added load on the service conductors and transformer when you add a second kitchen, water heater, HVAC system, etc. to them.

The second service would have its own set of service conductors as we would need to install new. Additional loads would be dependent on what the second tenant uses their space for. Could actually be no load increase at all. If there is a load increase we need to file the loads to the utility company and they determine if an increase in transfomer size is necessary and they provide the upgrade.

 

[Sparky2791]

Interesting approach I never considered calling capacity a load calc versus going off the size of the service. I have always thought of it the way Augie and Augie's AHJ thinks about it.

Yes - Even if you have a 3000A service the capacity of the service needs to exceed the 2000A before a second service is permitted under this section. So we have to prove by way of electric bills that show peak demand we are over the 2000A. Just because the service is rated for 3000A does not mean the capacity requirements are exceeding the 2000A.

 

[Sparky2791]

I had a similar conversation this week with ahj in my town. What I was told is that a rated wall was not required, but if it isn’t a rated wall, I would need to group the services. If it is a 2hr rated wall, the services could be split. They have some building size requirements that determine whether a rated wall is required. The structure we were discussing is 10,000 sq/ft, and rated walls are not required. I can’t remember if the threshold was 10k or 12k sq/ft, but over that size would require sprinklers and rated walls between the tenants. It’s worth a call to your ahj to discuss building code requirements.


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It would seem that 230(B) (1) would allow it regardless. Not enough space to locate in one spot permits it to be located separately on the same building