We're are doing some home renovations on a budget and I was wondering
if someone could help me with some electrical questions.
1) What would be the best (easiest) way to run a new circuit to the 2nd
floor bathroom. Since it's an old house I would like to add a new
circuit for the wall receptacle and the radiant heat flooring I plan to
2) The floor heating will be drawing 1020W - 9.2 A according to the
manufacturer. Is there a problem having it on the same 20A circuit as
And depending on how old the house is, it may be balloon framed, so you
may have a straight shot from basement to attic for fishing the run,
and then it should be pretty easy to run to where it needs to go.
I'm not an electrician, but I would think you would want two runs, one
dedicated for the wall outlet, and a separate run for the floor
I'm sure the electricians here can set you straight on that one.
The house was built in 1958, the bathroom on the second floor and the
main panel is in the basement. Ideally I would like to run the new
wiring to the attic where I have access to the most of the bathroom
I though of 2 possible locations I may be able to run it:
1) I have a brick chimney on the side of the house for a fireplace that
has now been converted to a gas. I know the previous owner has run some
wiring up there for the gas fireplace on the main floor. This chimney
is visible in the attic.
2) There is an unused laundry shoot but this will only get me to the
second floor and on the opposite side of the house, where the bathroom
Thanks for all the information guys!
I've replaced the existing receptacles with GFCI units and the Nuheat
thermostat has a GFCI built in. Unfortunatly the main stack takes a
bend somewhere in the kitchen area and so I don't think I can manage a
run up that way. Blocking between the wall studs also makes wiring
difficult without breaking open the paster wall. I'll try my luck with
the chimney and if that doesnt work I'll probably end out trying a
conduit like someone mentioned before.
Once last question, I've go one receptacle that was left behind when we
got rid of one bedroom to expand this new bathroom. I've installed a
GFCI repalcement on it for now but I guess the safe way to do it would
be to rewire it or put a cover on it...
If it's not in a location that you need an outlet, put a blank plate on it.
Another possible route to the attic is through closets. If you find one on
the first floor directly under one on the second floor, you can drill a hole
in the corner through both and run a conduit
If you want to abandon the leftover receptacle, trace the branch to the next
previous receptacle and cut or remove the wire from that end. Now the wire
in the leftover j box is dead and you can tear it out or cover it up.
If you just remove the receptacle at the end and otherwise leave a live wire
inside, you can only cover it so that it can be accessed in the future if
needed (code says you cannot bury a live J box in a wall). GFCI is needed
only on the first receptacle in the branch, any others downstream are not
required unless you are trying to compensate for wiring that has no grounds
but still want 3 pronged outlets.
If you do go with conduit, use the NM gray plastic type, it is infinitely
easier to work with (bending and cutting) and requires fewer fittings (glue
joints not bushings) and need not be bonded (grounded) at both ends as would
be required with metalic conduit. Also it is not advisable to use NM
jacketed wire (like romex) inside the conduit, use seperate wires and it
will be much easier to pull and you can get more circuits in the same size
You might be able to snake 2 - 12/2 romexes along side the plumbing stack
that runs from the basement up to the roof. Shine a light upwards from the
basement where the stack goes up into the floor. Then go up in the attic
and look down along the stack to see if any light is visible.
If you see light then you may have a clear shot at pulling cables up to the
attic. Use a length of #10 jack chain or a good string with a piece of
chain attached to it and drop it down along side the plumbing stack from the
attic to the basement. If you're lucky the chain may pop right out into the
basement. If not, you may need a fish tape to try and hook the chain. A
helper would be handy for this project.
The bathroom receptacle is required to be on its own 20 amp circuit and it
is not a bad idea to have the heater on its own as well.
When running the cables in the attic, do not run them across the ceiling
joists. You can drill from joist to joist and run the wires through holes
or you can install running boards and staple the cables to the sides.
Current NEC, requires a dedicated 20 amp GFCI protected outlet in your new
bathroom and as your floor heating will require a dedicated circuit as well,
the easiest thing to do is run a 12/3 cable (two circuits) up from the panel
to the outlet box in the bathroom,(use a large box) and branch off of that
box with the second circuit to your heating control and heater
Marc - Wire is cheap when compared to the time to figure out and pull a run.
If it were me, I would pull one circuit for the heat, one for the outlet and
one for future use while I was at it. Conduit is cool but hard to retrofit,
compared to just pulling a wire or three.
1. You can see for yourself if there is a good path in the walls to run the
wire (with minimal hole punching) or you can run a conduit on the exterior
of the house and enter through the wall at the point you need it to be. I
assume your panel is up to the task of adding two more 20A circuits. A
bathroom must absolutely have a GFCI breaker in either the panel or the
first receptacle on the branch.
2. code requires a separate branch circuit for permanently connected heating
apparatus. You need a way to turn it off without turning anything else off.
At 110V your amperage is correct. Might be a bit less at 115V or 120V (for
the same wattage). Furthermore the load calculation must take the heater
into account at 100% of its rated ampacity while other loads (most
receptacles) only add 40% to the total current needed in the panel. This
may be an issue if you are adding to a 100A or 125A service or if your home
is very large and maxes out even a 200A box. In general if you have open
slots in the panel you can use them but if you are pulling out single
breakers to put in double ones to increase the number of branches you need
to pay attention to the limits.
Yahoogle "load calculation example" for more help
Can't say not knowing the construction. Sometimes it is easiest to go up to
the attic through a closet of along a chimney and then down to the bathroom.
Yes. The new receptacle must also have a GFCI. It is not advisable (and
maybe not to code) to have heating and a receptacle on the same circuit.
Doing it on a tight budget is OK, but do is safe and do it right.
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