One-Family Dwelling

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cirelo132

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What exactly is the definition of a "One-Family Dwelling"? Specifically, I want to know if a unit in a high-rise residential condo, where each unit is separately metered, is a "one-family dwelling", for purposes of NEC 230.79(C).

Any thoughts?
 
While each unit might be separately metered, does each get a set of "service conductors" from the utility? Or does the utility provide one service to the condo building as a whole, with separate "feeders" (each with its own meter) being supplied to each unit? I ask because if it is the later, and I suspect it is, then you are not in 230 at all.
 
That makes sense. However, the reason I was even thinking of this is because 230.79(C) does not allow services less than 100 amps.

If the building has one set of service conductors from the utility, and the units are powered by individually metered feeders, then according to articles 215 and 220 can I use an 80 amp panel as the main panel for the unit?
 
A one-family dwelling is typically a detached structure located on a individual lot. A one-family dwelling is sometime attached to another one-family dwelling. These structures are usually under the provision of a "residential code", aka one- and two- family dwellings. Structure with 3 or more dwellings is usually under the general building code. The one exception is townhouses.
 
If a load calculation performed per 220 tells you the total load (i.e., 100% of non-continuous load plus 125% of continuous load) is below 80 amps, then you can certainly use an 80 amp panel for each unit. But can you find such things? I though the next size up from 60 amps was a 100 amp panel.
 
I believe what is being installed is a 100 amp panel, MLO, protected by an 80 amp breaker located at the meter.

Is there somewhere that has the specific definition of a one-family dwelling? The building is in Florida, so would it be somewhere in the FBC? or is that in the NEC? I am just curious...

Thanks for the help guys!
 
cirelo132 said:
Is there somewhere that has the specific definition of a one-family dwelling?
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Try NEC Article 100. There are four related definitions, beginning with "Dwelling Unit."
 
Here ya go....Enjoy !

Dwelling, One-Family. A building that consists solely of
one dwelling unit.

Dwelling, Two-Family. A building that consists solely of
two dwelling units.

Dwelling, Multifamily. A building that contains three or
more dwelling units.
 
Wow, I feel like an idiot. I was looking for that yesterday, and couldn't find it.

But hey, live and learn, right? Thanks!!
 
Hey Charlie B....I got one for ya....along those same lines say they combine two condo's together and each unit ( which is now being made one single unit ) has a panel in each side....and a different meter enclosure for each section.

So basically you now have one large condo with (2) panels each with it's own meter in the same floors electrical room.....got any problems with it?
 
I think you would have a problem with 230.2. You would not meet any of the exceptions. You might be able to talk the AHJ into letting it stand as an existing condition. Or you might be forced to turn one of the two panels into a sub-panel that is fed from the other.
 
lol.......well to be honest Charlie....they would need to change this installation and get it to be (1) meter....not many AHJ's ( or my boss anyway ) would allow the installation with (2) different meters....even if existing( atleast again in my specific area..not sure other areas )

Basically felt it would be interesting to add....since each of these are feeders from the electrical panel room to what was indivisual units but since they were individual units and are nowa single large unit.....they need to remove it from being (2) meters.....just figured you would find it interesting.....
 
FYI....that was the local AHJ's decision on the above back some time ago....but lets kink it a bit charlie....

What if the meters and main service disconnect ( and it does only have a single service latteral or exceeds 2000A and brings that exception in for an additional service....just for argument sake ) and so now you have a main disconnect ahead of the individual meters as well as individual disconnects for each unit....can a dwelling unit have multiple panels with their own meters......taking out the issue of 230.2
 
radiopet said:
. . . . can a dwelling unit have multiple panels with their own meters . . . . taking out the issue of 230.2?
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Sounds OK by me. But why would you need those extra meters? To be able to charge the Mother In Law for electrical energy in addition to rent for her portion of the house?
 
Charlie....this is a multifamily building( about 25 units per floor i believe ) and each floor has an equipment room with the meters for each unit. In this case it is a 25 story high rise condo/apartment community. In fact Mayor Douglas Wilder lives in the building....very pricy units.
 
radiopet said:
So basically you now have one large condo with (2) panels each with it's own meter in the same floors electrical room.....got any problems with it?
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I don't and here the AHJs do not either when it is a remodel / reconfiguration type situation.

It is also very common in strip malls, I recently combined 3 spaces into one large space they now have 3 - 200 amp feeders each with their own meter.

For the fire Dept we label them 'Main 1 of 3', 'Main 2 of 3' etc.
 
The City ended up having no problem with it........figured you all would have different views on it. Basically since we are dealing with feeders I have no problem with it either....not sure why but the POCO was throwing a fit about it if I recall from stories the guys tell me....back a few years ago I believe.
 
A One Family Dwelling is a building that has one dwelling unit. In the International Building Code, a condo is an R-2 use group which is Apartments(multi-family), Boarding houses, Convents, Dormitories, Timeshare properties, etc. So a condo is a dwelling unit. For the purposes of NEC sec 230.79(C) I think it refers to a building with one dwelling unit.
 
construct said:
A One Family Dwelling is a building that has one dwelling unit. In the International Building Code, a condo is an R-2 use group which is Apartments(multi-family), Boarding houses, Convents, Dormitories, Timeshare properties, etc. So a condo is a dwelling unit. For the purposes of NEC sec 230.79(C) I think it refers to a building with one dwelling unit.
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If the unit is served by a feeder assembly, not a service, see 215.2(A)(3). Study example D4 in Annex D to see how a building with 40 dwelling units can end up with a 434 ampere service -rounded up to 450 as per 240.4(B)- with feeders loads as little as 49 amperes. These certainly would not have to be fused at 100. :smile:
 
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