I am building (I am the buyer, not the builder) a house in NC and was told that NC code requires the dishwasher to be on a circuit that can be turned off with one of the lightswitches in the kitchen, whats the basis for this?
I was happy to see AFCI's for all of the bedrooms.
In Alaska where I just left all "fixed" appliances are now required to have a means of disconnect as per 422.31(b).
This means that dishwashers, garbage disposals, waterheaters, range tops, wine coolers, built-in fridges, wall ovens, and any other fixed in place appliance that you can think of has to have a disconnect within sight. This can be a disconnect, a switch, or a cord and plug.
While I am not famliar with the local N.C. code this would seem to be an attempt to comply with the above referenced code article. You should consult your local AHJ (Authority Having Jurisdiction...your city, county, or state inspectors that have authority there and see if another means of disconnect is adequate. In order to comply with this most dishwashers nowadays are "plugged-in".
I think perhaps what the installers/electricians/whomever it is doing the install were trying to tell you is not that you would have a wall mounted switch that shuts off the dishwasher alongside the light and disposal switch. But rather that they needed to install a switch inside the cabinet where the dishwashers feed originates from. An alternative is for them to install a receptacle at the outlet and a cord on the dishwasher. As long as the cord length/wiresize is kept within the code limits.
Whoever qouted this code rule is correct but don't forget that there are several ways of complying with it. Since this is new construction you must comply with the "new" code as upheld in your area.
If that’s true I would say that the NC inspection authority must be way behind the times and incapable of reading and applying the current NEC. 422.31 is completely overwritten by 422.33 if you use the cord and plug connection allowed in 422.16 in compliance with, 400.5, 400.7, 400.8 and 210.21[B]. Most appliance manufactures recommend this type of connection. It is easily done and generally considered as a much safer and more professional installation. Once the cord is removed, the appliance is completely disconnected from the power source and there is no unsupported cable of unknown length flapping around below the appliance. Someone should also explain to them that running a cord though an adjoining cabinet is not restricted by 400.8 because they are not considered walls of the structure. Some interpret 422.16 to say that you can install the receptacle in the same space occupied by the appliance and not even be able to get at it once the dishwasher is installed and still comply with the definition of accessible in Article 110.