Help Interpreting NEC 240.24(B) - Each occupant shall have ready access to all OCPDs

[hbiss]

I have been hit with this several times when dividing up tenant spaces, it can be quite a expensive item for an estimator to overlook.

Well, if you didn't realize that the tenant panels have to be accessible to the tenant, that's on you. If they are and not made accessible that's on the owner.

Another pitfall would be a large resort property with individual dwellings scattered about, think ranch type resort or YMCA retreat center with about 100 dwellings that are rented there is one large 7200V service to the property, everything else is feeders.
240.24(B)(1) requires each house to have access to the service of the property, which would be a 7200V service.

I would think that each dwelling would have a panel with a main breaker within it. However, to require that they also have access to 7200V switchgear is preposterous. That's like saying that a homeowner should have access to the utility companies' substation.

Sometimes you have to think a little bit.

-Hal

 

[jaggedben]

Another pitfall would be a large resort property with individual dwellings scattered about, think ranch type resort or YMCA retreat center with about 100 dwellings that are rented there is one large 7200V service to the property, everything else is feeders.
240.24(B)(1) requires each house to have access to the service of the property, which would be a 7200V service.
There are been code change proposals around this to add dwelling units to 240.24(B)(1) but they got rejected.

I was recently at a resort type place, it's a bunch of cabins. Being who I am I noticed each cabin had a panel on the outside with a PVC pipe coming out of the ground, and then I also noticed a transformer next to a panel on a pedestal, walked up to it and it was unlocked and I opened it and saw breakers labeled for all the cabins in the group we were in. My point being, I guess, that depending how you design things there's no reason you are necessarily likely to end up violating the piece of code we're discussing.

Personally I think that if each cabin's panel had a main breaker (I didn't look) then there would be no violation if that panel on the pedastal were locked or otherwise inaccessible.

 

[tortuga]

I was recently at a resort type place, it's a bunch of cabins. Being who I am I noticed each cabin had a panel on the outside with a PVC pipe coming out of the ground, and then I also noticed a transformer next to a panel on a pedestal, walked up to it and it was unlocked and I opened it and saw breakers labeled for all the cabins in the group we were in. My point being, I guess, that depending how you design things there's no reason you are necessarily likely to end up violating the piece of code we're discussing.

Personally I think that if each cabin's panel had a main breaker (I didn't look) then there would be no violation if that panel on the pedastal were locked or otherwise inaccessible.

While that might look like a service its all feeders, 240.24(B)(1) requires each dwelling unit to have access to the 'service' of that property, that would be whatever is feeding the transformer a substation or switch-gear.

 

[jaggedben]

I have never understood the requirement to apply to the service if the occupancy is a structure fed by a feeder. That's ridiculous, frankly. But maybe this code language really does need an update.

 

[tortuga]

I have never understood the requirement to apply to the service if the occupancy is a structure fed by a feeder. That's ridiculous, frankly. But maybe this code language really does need an update.

Yeah a smaller scale example is this new trend of homeowners putting mother inlaw cottages, tiny houses or better known as Detached Accessory Dwelling Units (ADU) in their back yards. The way the permitting works now is they get their own address and are considered a independent dwelling unit, however some really are for in-laws or are short term rentals like air-bnb so the homeowner opts to include utility's saving the cost of a 2nd meter for water, power, gas etc.
The ADU's are supplied by a 100A feeder and have a 100A main breaker panel inside accessible to the tenants so there is no doubt they have access to their branch breakers, but
Since 240.24(B)(1) requires each dwelling unit to have access to the 'service' of that property inspectors are requiring the service equipment for the primary dwelling to be located outside.
Others and myself have had to appeal this up to the state level to get an exemption.
My argument was that an ADU meets the definition of a guest suite and thus is exempt.

 

[dlukert]

Well, if you didn't realize that the tenant panels have to be accessible to the tenant, that's on you. If they are and not made accessible that's on the owner.



I would think that each dwelling would have a panel with a main breaker within it. However, to require that they also have access to 7200V switchgear is preposterous. That's like saying that a homeowner should have access to the utility companies' substation.

Sometimes you have to think a little bit.

-Hal

I'm still stuck on this - but how many commercial office buildings do you know of that allow tenants access to the electrical rooms? Every time I've tried to access an electrical room with a tenant they have to call the landlord/building maintenance

Can I remind you of Charlie's rule... the code says what it says, and it being 'preposterous' is not really relevant to what's actually in the code - I wish inspectors and AHJs would accept that argument sometimes

 

[dlukert]

Yeah a smaller scale example is this new trend of homeowners putting mother inlaw cottages, tiny houses or better known as Detached Accessory Dwelling Units (ADU) in their back yards. The way the permitting works now is they get their own address and are considered a independent dwelling unit, however some really are for in-laws or are short term rentals like air-bnb so the homeowner opts to include utility's saving the cost of a 2nd meter for water, power, gas etc.
The ADU's are supplied by a 100A feeder and have a 100A main breaker panel inside accessible to the tenants so there is no doubt they have access to their branch breakers, but
Since 240.24(B)(1) requires each dwelling unit to have access to the 'service' of that property inspectors are requiring the service equipment for the primary dwelling to be located outside.
Others and myself have had to appeal this up to the state level to get an exemption.
My argument was that an ADU meets the definition of a guest suite and thus is exempt.

tough argument if there's an oven or range in there...

I mainly work in the commercial world myself, and have only recently seen a plan reviewer enforce it, but I've got a meeting scheduled to discuss it with them further

I have never understood the requirement to apply to the service if the occupancy is a structure fed by a feeder. That's ridiculous, frankly. But maybe this code language really does need an update.

Couldn't agree more that this needs an update, but it seems like it's just so rarely enforced or thought about outside of residential - maybe that's the intent but it would be nice for that to be clarified

 

[tortuga]

My argument was that an ADU meets the definition of a guest suite and thus is exempt.

tough argument if there's an oven or range in there...

It was, however all I had to do is prove there is nothing mutually exclusive about the NEC definitions.
For example the standard 120V duplex receptacle on the wall behind your desk is both a 'outlet' and a 'receptacle outlet' per the NEC definitions. Once its defined as an outlet it still can meet other definitions such as receptacle outlet.
So there is nothing that prevents a unit from simultaniously being a dwelling unit and a guest suite if it meets both definitions.
A guest suite as defined in the NEC is:

An accommodation with two or more contiguous
rooms comprising a compartment, with or without doors between
such rooms, that provides living, sleeping, sanitary, and storage
facilities.

The definition of Dwelling Unit is:

A single unit, providing complete and independent living
facilities for one or more persons, including
permanent provisions for living, sleeping, cooking, and sanitation.

So one could create a truth table or vinn diagram comparing the two definitions and you can see nothing precludes one from also being the other:

​	Dwelling unit​	Guest suite​
Is a single unit​	TRUE​	TRUE​
Has two or more contiguous rooms with or without doors between such rooms​	Optional​	TRUE​
Consists of a compartment (part of a larger occupancy)​	Optional​	TRUE​
Has permanent provisions for Living​	TRUE​	TRUE​
Has permanent provisions for sleeping​	TRUE​	TRUE​
Has Sanitary facilities​	TRUE​	TRUE​
Has permanent provisions for cooking​	TRUE​	OPTIONAL​
Has Storage facilities​	OPTIONAL​	TRUE​

 

[dlukert]

It was, however all I had to do is prove there is nothing mutually exclusive about the NEC definitions.
For example the standard 120V duplex receptacle on the wall behind your desk is both a 'outlet' and a 'receptacle outlet' per the NEC definitions. Once its defined as an outlet it still can meet other definitions such as receptacle outlet.
So there is nothing that prevents a unit from simultaniously being a dwelling unit and a guest suite if it meets both definitions.
A guest suite as defined in the NEC is:

The definition of Dwelling Unit is:


So one could create a truth table or vinn diagram comparing the two definitions and you can see nothing precludes one from also being the other:

​	Dwelling unit​	Guest suite​
Is a single unit​	TRUE​	TRUE​
Has two or more contiguous rooms with or without doors between such rooms​	Optional​	TRUE​
Consists of a compartment (part of a larger occupancy)​	Optional​	TRUE​
Has permanent provisions for Living​	TRUE​	TRUE​
Has permanent provisions for sleeping​	TRUE​	TRUE​
Has Sanitary facilities​	TRUE​	TRUE​
Has permanent provisions for cooking​	TRUE​	OPTIONAL​
Has Storage facilities​	OPTIONAL​	TRUE​

that's a really interesting point regarding dwelling units and guest suites - I hadn't considered that before
I was more worried about where it specifically says 'dormitory units without permanent provisions for cooking...' which I assume was intended to apply to guest rooms/suites as well

 

[tortuga]

I also had to argue the 'Consists of a compartment' part, detached structures that depend on a parent structure for their primary electrical supply, such as Detached Accessory Dwelling (DADU) or Other Units such as cottages or cabins that are dwelling units can considered ‘compartments’ if they could not receive electricity directly from a independent utility meter (if they are on a feeder from a main service). But thats more of a stretch, and if an AHJ does not buy that then in like Bens cottage example, he had access to his feeder disconnect but per the letter of 240.24(B)(1) each occupant would be required to have access to the service switchgear for the entire campus, since a campus is not a 'Multiple-occupancy building'