New house

[Ajr188]

Good morning.

I am in the process of roughing this tiny 660 sq ft house, that has 3 bed rooms. My question to you guys is can I put multiple bed rooms on 1 15amp circuit or do I have to to run each bed room separately. There is literally 4 outlets per bed room and one led light in middle of room.

 

[augie47]

Short answer: Yes
The NEC allows 600 sq ft per 15 amp circuit for bedrooms, etc.

 

[LarryFine]

The NEC allows 600 sq ft per 15 amp circuit for bedrooms, etc.

Is that a new real rule, or a theory extrapolated from the load-calc section?

 

[Johnhall30]

The load calc section at 3 watts/ sq foot would allow 480 square feet for a 15 amp circuit

 

[Chamuit]

I used to use 10 openings per circuit in lighting as a general rule. This meant 1 1/2 rooms per circuit.

The first house my wife and I bought had the hall bath, two bedrooms, laundry lighting, garage lights and receptacles, plus the exterior receptacles all on one circuit. So, you can see how far a circuit can be stretched. But, if the breaker tripped, half the lights in the house were out. Usually happened when the Christmas lights were plugged in. I ended up splitting the circuit into three by dropping a 3-wire in the middle of the circuit.

 

[augie47]

Is that a new real rule, or a theory extrapolated from the load-calc section?

210.11

The load calc section at 3 watts/ sq foot would allow 480 square feet for a 15 amp circuit

15 amps @ 120v = 1800 watts + 3 = 6-- sq ft.

 

[Johnhall30]

210.11

15 amps @ 120v = 1800 watts + 3 = 6-- sq ft.

You are only supposed to load a circuit to 80 percent.

15 amps x 120V x .80 = 1440 watts

 

[Ajr188]

So do I need 1 circuit per room or can I put more lol

 

[Johnhall30]

By code, you will need two 15 amp circuits to feed the lighting and receptacle load for this house

Not counting the other required circuits, such as the laundry area and kitchen small appliance circuits

 

[Chamuit]

I saw a note on a drawing that said that 1.5VA/sq ft could be used in some jurisdictions if home complied with energy efficiency requirements. That would double the square footage.

 

[Chamuit]

So do I need 1 circuit per room or can I put more lol

Remember, NEC is minimum, not best design.

 

[Ajr188]

What I wanted to do was split the circuits up even between the 3 bed rooms. This house is like the size of my garage very small

 

[kwired]

I'm in the camp that thinks one circuit is fine. Though I myself likely run a 20 amp circuit for all the receptacles and possibly a 15 for the lights, but also will include lights from other areas on that 15 amp circuit.

Particularly on a new home or major remodel. On an old home the chances of needing window A/C's or portable heaters might increase the possibility of installing more circuits though. New or major remodel the HVAC is likely covered well enough those portable units not as likely to be needed. Take those away and there usually isn't all that much for load in a bedroom, or if there is it is usually a short term load.

 

[Ajr188]

let’s try this.

How many circuits would you run for this house total!?

2 - 20 amp small appliance branch circuits
1 20 amp refrigerator line
1 20 amp bathroom circuit
2 15 amp outlet circuit
2 15 amp lighting circuit
1 2 pole 30 for dryer !?

Mind you this cottage has 100 amp panel

 

[Dennis Alwon]

let’s try this.

How many circuits would you run for this house total!?

2 - 20 amp small appliance branch circuits
1 20 amp refrigerator line
1 20 amp bathroom circuit
2 15 amp outlet circuit
2 15 amp lighting circuit
1 2 pole 30 for dryer !?

Mind you this cottage has 100 amp panel

I would probably have done what you suggested here. It is more than required by code. What about range and heating?

 

[kwired]

let’s try this.

How many circuits would you run for this house total!?

2 - 20 amp small appliance branch circuits
1 20 amp refrigerator line
1 20 amp bathroom circuit
2 15 amp outlet circuit
2 15 amp lighting circuit
1 2 pole 30 for dryer !?

Mind you this cottage has 100 amp panel

That is no problem for a 100 amp supply, seen similar to that plus electric range, AC, WH, DW/Disp and even some additional electric baseboard heaters in basement rooms all on 100 amp supply and never a complaint of tripping the main. Lived in house with exactly what I mentioned at one time.

 

[Ajr188]

That is no problem for a 100 amp supply, seen similar to that plus electric range, AC, WH, DW/Disp and even some additional electric baseboard heaters in basement rooms all on 100 amp supply and never a complaint of tripping the main. Lived in house with exactly what I mentioned at one time.

Oh yea I missed dish washer and heater.

Now my last question is even tho the panel is exsisting am I required to bring grounding up to code even tho I’m not filing the job.

 

[Dennis Alwon]

Oh yea I missed dish washer and heater.

Now my last question is even tho the panel is exsisting am I required to bring grounding up to code even tho I’m not filing the job.

Imo, if you enter the panel and add a circuit to it then you are responsible to bring it up to code. It is not defined in the nec but each state may have their own interpretation.

 

[kwired]

Oh yea I missed dish washer and heater.

Now my last question is even tho the panel is exsisting am I required to bring grounding up to code even tho I’m not filing the job.

What is the "grounding issue"? Improper GES installation isn't exactly part of the task of installing a new circuit, installing a new circuit to a feeder panel that doesn't have an EGC however - one can ask where should you connect the EGC?

Some jurisdictions maybe do have rules/allowances that take those situations into consideration where others don't address it at all and it ends up being inspector's discretion.

 

[Ajr188]

Imo, if you enter the panel and add a circuit to it then you are responsible to bring it up to code. It is not defined in the nec but each state may have their own interpretation.

If that was the case most service calls I do i would lose money on fixing other peoples violations…… hard to convince a customer they have to pay for that