I'm putting an addition on my house and want to do the electrical myself,
I'm allowed by code in NJ. I've done a little in the past but nothing this big.
Approx. 800 sq. ft, BR, LR, Bath & Landry room. My ques. is how many
outlets/ceiling light fixtures can I put on one breaker, is there a formula,
or rule of thumb? Do any appliences need there own?(like washing machine)
I have allready had a 200 amp upgrade done and have plenty empty
breaker slots. Thanks in advance for any advice.

 

There are hundreds of rules you must follow, but how many outlets you can put on one breaker is not one of them (unless there is a local NJ code for this). Rule of thumb says no more than 8 on a 15-amp circuit and 10 on a 20-amp circuit.

All the rooms you mention have very specific rules. Bedrooms need AFCI in many areas. Bathrooms usually need their own 20-amp circuit with GFCI protected receptacles, at least one within 36" of each sink. Laundry areas need dedicated receptacle circuits (but not necessarily dedicated to the washing machine).

The above paragraph just barely scratches the surface. Find at least three good (and recent) books on home wiring and read them cover to cover.

 

The bathroom will need its own dedicated 20A circuit. The laundry room will also need a 20A circuit for the washing/drying machine. As for the rest, there is no limit, but you need to use common sense. Typically it's about 10 outlets on a 20A circuit, but it's not the number of outlets that matter, it's what you plug into those outlets. Lights are the same, some lights have one one light bulb, some have 20 light bulbs.
I would run a 20A circuit for the bathroom, a 20A circuit for the laundry room (washer/dryer outlet), a 20A circuit for the bedroom and 2 20A circuits for the LR (1 for the general purpose outlets/lights, including any hallways and laundry room lights and 1 for the entertainment center (if you have one).
Depending on how comfortable you are with electrical work you can run multiwire circuits to save some wire.

 

Thanks for the quick reply, I thought it had something to do with
calculating total wattage on the breaker. for a follow up ques.
does an outside outlet need to be on it's own breaker, or can
I tap off an outlet in the LR, and put a GFCI out there?

 

Yes, you should calculate the total wattage and compare it to the breaker capacity. But of course a receptacle uses no power by itself so there's always the question of what you count it as. In commercial work, the code tells you how to count it, but not so in residential work.

You can legally tap off the LR, although it might not be a great idea since the LR circuit was designed for the outlets it currently it has. Depends on what you plug into the LR and what you plug in outside. Don't forget the vacuum cleaner.