I am doing some engineering research for the electrical renovation of an existing early 1980's vintage, 8 story, ocean-front high rise hotel. The owner is converting it to time share condominium uses. My question is about what electrical equipment is allowed below the base flood elevation, what equipment is required to be above this level, and what Code, or governmental regulatory standard addresses these issues. Thanks for the input
FEMA will identify flood hazardous areas. Local building code will tell construction methods. Local zoning will adopt the FEMA standards. Electrical equipment below the flood zone will be in a wet location, and all equipment will have to be gasketed and watertight. What we usually do is to build the house on stilts, and keep all electrical equipment above the flood level. Any wiring below has to have a "W" in the insulation.
Re: Flood Zone Requirements#57415 10/14/0511:38 AM10/14/0511:38 AM
If it was really true that anything below flood plain was required to be "water tight" I would need gasketed boxes in my living room. (FF is at 9' above sea level.) They don't do anythinbg special in South Florida. If the wiring is outside it gets done the same as any other outside wiring. If the area is a "utility space" (a euphamism for living space below flood) it uses normal inside wiring methods. In Florida "flood" is <11' above sea level. On a piling house it is very common to have the bottom floor enclosed with "blow out" walls and calling it utility space. They get wired with romex and blue Carlon nail ups.
Re: Flood Zone Requirements#57416 10/14/0512:35 PM10/14/0512:35 PM
In Honolulu, the requirement is to make all circuits below the fz level be protected by a gfi. So like South Florida, most new houses in the defined flood zone are up on stilts and the outlets and switches and so forth that are at grade level, have to be gfi protected. Where this whole thing is retarted is that the poco still demands the meter/main to be 5-6' ft high off of grade level, which I think sort of negates any branch circuit protection if the water levels get over the height of the meter/main can.
Re: Flood Zone Requirements#57418 10/15/0508:26 AM10/15/0508:26 AM
In NJ, new construction needs all mech equip. to be installed above Fz area. It is common to see HVAC units on 2nd floor decks, on roofs, or on raised platforms. We are having flooding rains yesterday and today as we speak in one of the towns that I inspect. As for equipment that goes under water, it has to be re-examined by a listing agency or replaced. An EC can give a letter saying that it is OK, but I don't know of many that will do that.
Re: Flood Zone Requirements#57419 10/16/0509:23 PM10/16/0509:23 PM
Mike is talking about vitrtually the same rules as they have here. On a piling house the meter can is going to be at grade. That reader is not climbing stairs all day. They won't move the bushes over. The GFCI (remember "utility area")sort of negates the idea of "replacing all the wiring" after a flood. If it holds the GFCI it is dry "enough".