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buckrogers
Mar 17, 2008, 03:50 PM
I'm starting a pretty large basement project and some good advice on my circuit plan will be welcome.

My house is pretty new (less than 3 years old) and I believe I have 200A on the distribution board. The new planned living space in the basement is about 1400sqf.

This is my first attempt at a circuit diagram.
20A - 14 Lights Bar/Game/Hall
15A - 12 Lights Fam/Gym/Store
15A - 11 Lights Office/Hall/Bed/Util
15A - 8 Outlets Game/Fam
15A - 10 Outlets Office/Hall/Bed
20A - 9 Outlets Gym/Bar.Store
20A - Bath Lights and Outlets

Two questions to start with:
1) Any suggestions for a better circuit layout?
2) How many circuits (breakers) can I add to my existing system?

Thanks
Chris
New Hampshire

xxluvmexxhatemexx
Mar 17, 2008, 04:17 PM
You may need 2 to 3 circuit breakers

donf
Mar 17, 2008, 04:20 PM
Chris,

#1 - Call a licensed electrician to review your plans. Apart from red, blue and black lines running all over the place without description. Is Red = 20 amp, Black = 15 amp, Blue = ? Where is the SEP with respect to the basement. Have you put together a better set of plans to submit to the LRA for your permit application? Did you do any load sizing from the calcs in the NFPA section 70 code book? Where is the GFCI for the bathroom and bar?

You need to add a specs page detailing the electrical circuits gauge wire to be used where the outlets are to be and the loads to expect for them.

2) See the open panel door, count the blank slots. That's the number of spare slots you have.

I'm going to pull your pics into photoshop to see if I can make more sense of them by blowing them up. Do you know what formulas you need to do the circuits in the basement?

Stratmando
Mar 17, 2008, 04:25 PM
I see maybe 7 to 8 or more, not counting a 2 pole?(240 volts? For Water heater). Have each room on its own circuit.
Don't forget computer, speaker, alarm, anything else now. Doesn't get easier or cheaper than now.
Supposed to do Load Calculations, You are probablay OK, I see 2 Pole breakers, the rest single pole.What do you currently have?

buckrogers
Mar 17, 2008, 08:05 PM
Thanks for the replies. I'm not as far along as you may think, I just started with the electrical planning. I was hoping to get some expert advice from this forum before going too far.

First thing, I'm limited to the image size I can upload, so here are some better images:
The basement circuit layout (http://xtremescan.com/images/misc/electrical.jpg)
Existing home panel (http://xtremescan.com/images/misc/IMG_4158.JPG)
Existing panel description (http://xtremescan.com/images/misc/IMG_4157.JPG)

The different colors are just to clarify my different circuits for now and have no special meaning. Black are the outlet circuits (and the bathroom), blue are lights, orange TV. I worked on a safe capacity of 1440 watts for 15A and 1920 watts for 20A.

I'll explain how I came to these
20A - 14 Lights Bar/Game/Hall (blue)
14 rececced lights (75-100W). I can probably splitt this in two 15A circuits
15A - 12 Lights Fam/Gym/Store (blue)
12 rececced lights (75-100W).
15A - 11 Lights Office/Hall/Bed/Util (blue)
11 rececced lights (75-100W).
15A - 8 Outlets Game/Fam (black)
The game room will not have any appliences. The Family room will have a TV and radio.
15A - 10 Outlets Office/Hall/Bed (black)
Nothing big planned for this circuit. One or two computer maybe).
20A - 9 Outlets Gym/Bar/Store (black)
The gym will have a TV and treadmill. This circuit includes GFI outlets in the bar. Should I use a separate circuit for a small bar fridge, or will the 20A do?
20A - Bath Lights and Outlets (black)
The bathroom has it's own 20A circuit for the GFI, lights and fan.

Donf, sorry, not sure what the SEP is you refer to. I'll be using 14-gauge wire for the 15A circuits and 12-gauge for the 20A. Any advice on making my diagram easier to read? My books don't have many examples.

bolt in blue
Mar 17, 2008, 09:15 PM
A couple of thoughts for you. In this day and age, I wouldn't run any new 15 amp outlet circuits. 15 amps might be fine for you now, but when you put a few desktop computers and a color laser printer in the office or a true home theater in the family room, you'll be kicking yourself for not running 12 gauge wiring.

What edition of the National Electric Code (NEC) is in effect in your jurisdiction? I found out that my county in VA uses the 2002 code from the building department's website. Unless they have made changes to the code (which they should tell you), you will almost certainly need to have the bedroom outlets on an arc fault circuit breaker. You'll likely also need to have the bedroom lights on an arc fault protected circuit. Remember the hardwired smoke detector. If the rest of your smoke detectors are hardwired and linked, you'll probably need to have this one connected with them as well.

About your wet bar: they're treated the same as kitchens by electrical code. That means that you'll need two 20 amp circuits for small appliances along the counters. You can have the refrigerator on one of these circuits (it still has to have a countertop outlet on it to count), but most people around here recommend putting it on its own circuit as a safeguard against food spoilage in case of an unnoticed breaker trip. Every segment of counter over 1' in width will need an outlet. Plan on reading up on the kitchen electrical requirements - there's a lot of them!

Hope your project goes well. Looks like you have a lot of construction ahead of you. Wish I were motivated enough to get a project that big done around here!

stanfortyman
Mar 18, 2008, 04:11 AM
About your wet bar: they're treated the same as kitchens by electrical code. That means that you'll need two 20 amp circuits for small appliances along the counters. You can have the refrigerator on one of these circuits (it still has to have a countertop outlet on it to count), but most people around here recommend putting it on its own circuit as a safeguard against food spoilage in case of an unnoticed breaker trip. Every segment of counter over 1' in width will need an outlet. Plan on reading up on the kitchen electrical requirements - there's a lot of them!A wet bar is most certainly NOT treated the same as a kitchen. There is NO two 20A circuit rule and no rules regarding refrigerators.
The only common rule is the GFI rule, and even this is not the same. Wet bars use old "within 6' of the sink" rule for GFI protecting receptacles.

Just use common sense when wiring areas such as this.

Stratmando
Mar 18, 2008, 07:26 AM
Oh yeah, Smoke detectors and Arc Fault breakers, We can't, and I don't use #14.

bolt in blue
Mar 18, 2008, 10:33 AM
A wet bar is most certainly NOT treated the same as a kitchen. There is NO two 20A circuit rule and no rules regarding refrigerators.
The only common rule is the GFI rule, and even this is not the same. Wet bars use old "within 6' of the sink" rule for GFI protecting receptacles.

Just use common sense when wiring areas such as this.

My bad. Good to hear they have more common sense somewhere else than they do here! One of my coworkers had to jump through a lot of hoops with his wet bar to please the Loudon County, VA electrical inspector.

donf
Mar 18, 2008, 03:33 PM
Buck,

I'll be happy to dl the pics and take a look at them. Please bare in mind that folks like TKRussell, Stratmando, Keepitsimple, Labman and Stanforty are much more experienced at sizing circuits so bare with me if they correct my work, accept the corrections as Gospel.

As far as a general rule of thumb, the NEC uses a max of 10 outlets for lighting branch circuits at 15 Amp, using #14/2 AWG. (10*120*15) = 18,000 Watts.

Receptacle outlets are also suggested at a max of 10. It's your choice whether to use 15 or 20 amp breakers. My suggestion is to go to 20 amp
(10*20*20) = 24,000 Watts per branch circuit. You can use 15 amp receptacles on a 20 amp line. The conductor would be a #12/3 AWG.

In fact, if you want to save misery down the road and you do not mind the additional cost of the wire, you can wire everything using #12/2 so you do not have to tear out the #14/2 if you upgrade.

CAUTION: If you use #12/2 conductors for your lighting circuits, make sure you select 15 amp breakers and 15 amp loads.

You can use the standard 15 amp receptacles for your plugs and switches.

Gotta-run now.

stanfortyman
Mar 18, 2008, 04:48 PM
As far as a general rule of thumb, the NEC uses a max of 10 outlets for lighting branch circuits at 15 Amp, using #14/2 AWG. (10*120*15) = 18,000 Watts.We use the actual rating of the fixtures in figuring number of lights on a circuit. For instance, on a typical 15A lighting circuit you can have 19 recessed fixtures with a maximum wattage of 75 watts. Most of us don't go to this maximum number though.





Receptacle outlets are also suggested at a max of 10. The NEC proposes NO maximum for residential receptacles. We just use common sense in figuring circuits.
Commercial is different.





CAUTION: If you use #12/2 conductors for your lighting circuits, make sure you select 15 amp breakers and 15 amp loads.Don, you're really going to have to explain this one to me. WHY would you need a 15 amp breaker on #12 wire??

donf
Mar 19, 2008, 02:55 PM
Stan,

I'll go back and research my references, but I know I read the estimates in either the NEC or Ray Mullin's, "Residential Wiring"

WRT24 #12 v #14 wiring, that's just a statement of cost. An earlier poster had suggested that Buck wire everything with #12 AWG rather than using #14 AWG. If Buck were to do that, then he needs to be aware that the CB needs to be a 15 Amp breaker and the load cannot be more than 15 Amps.

Stratmando
Mar 19, 2008, 04:37 PM
I think #14 is a sign of Fruegelness, you limit what you can do. Once walls are up, it may be destructive to get a 20 amp circuit there. Why Limit what you can do throughout the house? Anyone know the difference between a 15 and a 20 amp breaker and wire? Is it worth it not to run #12.

donf
Mar 20, 2008, 08:18 AM
Okay,

First I will defer to Stan on the issue of 10 lighting and receptacle outlets.

However, using the formula, 3x1467/120 = x/15 = number of lighting circuits,
I came up with 3 lighting circuits. And using Stan's 75 watt average, and balanced runs, I came up with 3 circuits. Circuits 1 and 2 would carry 15 lighting outlets. Circuit 3 would carry 16 lighting outlets.

Stan, I didn't attempt to recalculate your outlets because your drawing brakes down at a point inside the Gym, on the left side by the closet door. It just stops there. Then you start a second string which also dead ends.

The problem is that although I found four separate "Blue" circuits. Only one circuit has power supplied to it from the SEP (Main Panel),the rest of your blue lines never go near the Main Panel.

I found 4 TV lines. 3 origination from the Main Panel. These cannot connect to the main panel. The satellite or cable would be the source for the TV's input signals. Not the Electrical Panel. Also, I question your design of the family room. You only have one outlet receptacle behind the TV. That would be fine if all your are going to put there is the TV, but if this is a Home Theater set up, you are going to need more outlets then that.

One final suggestion, use this diagram you have to plan your circuits. For example, on the lighting, use L1 for the circuit name and then designate each outlet with an L1.X to keep track of where you are. Since we are using Stan's load calculation, of 75 watts per outlet, I would suggest that you use the actual wattage values for each outlet. This will let you balance your lighting circuits a little better.

SEP means the Main Panel. It is usually located adjacent to the entry point of the service cables from the Power Company. In your drawing it is located on the right hand side of the Game Room wall,

One last thing, I did not find any black lines leaving the Panel Box, so where are you going to draw your feeder supply for your lights?

stanfortyman
Mar 20, 2008, 12:10 PM
I think #14 is a sign of Fruegelness, you limit what you can do. Once walls are up, it may be destructive to get a 20 amp circuit there. Why Limit what you can do throughout the house? Anyone know the difference between a 15 and a 20 amp breaker and wire? Is it worth it not to run #12.IMO this is NOT the case with most of us who do this for a living.
There is FAR more reason to use #14 than just money. It's not about being cheap, frugal or foolish. IT'S NOT ALL about the money! In fact, we could make more using all #12, at least on T&M work. With contract work using all #12 can lose you jobs if you are bidding against other contractors who have a clue what they are doing.
In fact, and in my own opinion, the "all #12" mentality is equal to the "bigger is always better" mentality, which we all know is an extremely flawed mentality.

Using #14 for lighting circuits simply makes sense. Anyone who has ever installed dimmers, 3&4 ways and multi-gang boxes can tell you it can get very crowded in those boxes. Using all #12 you are very likely to overfill boxes and guaranteed to have a hard time with dimmers and 3&4 ways.
Also, of course #14 can limit what you can do. Just like #12 can limit what you can do.
With #14 you pull more circuits. With #12 you have less circuit with more on each circuit.
If you wire a circuit using #12, yet you limit yourself to the amount of lights typically on a circuit wired with #14, and use a 15A breaker, then YOU are the foolish one.
There is NO reason to do this.

There is ABSOLUTELY NO REASON to use #12 for residential lighting circuits, other than of course voltage drop, which in a typical residence is not an issue.
If you really do "need" to get a 20A circuit somewhere, what is the point of having an existing circuit? You'll likely overload it in that case anyway, and will need to pull a new one regardless.

stanfortyman
Mar 20, 2008, 12:12 PM
WRT24 #12 v #14 wiring, that's just a statement of cost. An earlier poster had suggested that Buck wire everything with #12 AWG rather than using #14 AWG. If Buck were to do that, then he needs to be aware that the CB needs to be a 15 Amp breaker and the load cannot be more than 15 Amps.Again, WHY would he need to use a 15A breaker if he uses #12 wire??

Stratmando
Mar 20, 2008, 01:07 PM
If in conduit, 14 could be OK. Since most here use romex(solid) you can't usually easily upgrade to 20 without destroying walls. I don't know how many times I hear their treadmill or something else that needs 20 Amp, many times they are screwed, Could be nice to use a heater in any room in the house. I like to do thing right once and forget about it. This is cheaper in the long run, plus you reduce voltage drop on everything. I don't see a lot of houses with individual lighting circuits. I may se a bedroom on 1 circuit, another bed on another circuit, then I like 20 amps.
I also only use stranded even thought it is more expensive, I feel it is less stressfull on the switches and recepticles, It is a pain at first, having to teach a wire to stay straight.
Extension rings help provide the space to reduce cramping. I like room in the boxes.

stanfortyman
Mar 20, 2008, 01:15 PM
Then I see this as a location specific difference.
You keep mentioning "upgrades". This can happen any time and anywhere. If you plan ahead it is not an upgrade later. IMO ALL #12 does not equate to an upgrade, nor will it avoid one in the future.

We have attics and basements. I assume you have all slabs and very few usable attics down there. I think the conditions in my area are more typical to most folks in the rest of the country.
I can run a new circuit to most parts of almost any house, and frequently do.
For you guys you have to plan for EVERYTHING at the time of construction or get screwed later.
This is a BIG difference in work and constructions practices.

Stratmando
Mar 20, 2008, 01:51 PM
It is different down here/
On the bighter side, Every house I have done, I did with conduit, We have no basements down here.
I have added 3 240 volt wall AC's to 3 bedrooms. I did have to remove Fans, switches and recepticles to get an extra pair to these 3 bedrooms AC locations. If not for conduit in slab, would have had to do exterior conduit. I hate extra stuff on the side of houses(Conduits, wires), and eleminate exterior wiring every chance I get.

donf
Mar 21, 2008, 10:47 AM
Stan,

Please do not misunderstand me. I am not advocating the use of #12 AWG in place of #14 AWG. I was responding to an earlier response in this thread.

However, I really liked your response. It was very educational for me. Particularly wrt filling the box.

One minor point, this is a DIY venue. Rarely will any poster be worrying about bidding on a contract.