Doughless Not to get everbody in a twist, but the point of designing a circuit and placing electrical outlets on that circuit is so that it rarely has to trip. That's why we break our basements up into several circuits, because we plan to draw a lot of amps into that room. Provide too many opportunites to trip a circuit, and the widow or Russian immigrant who occupies your property after you die will find a way to keep tripping it. If you have 12 outlets in a room on one circuit, regardless of how they are spaced, they will trip it. Codes are written in a fairly prescriptive manner and don't always capture the intent behind the code. Inspectors enforce the written code and have no method of enforcing the intent. As has been said, the 12 foot spacing has to do with running cords all over the place within the room itself. It's so that widow or a future stroke victim doesn't kill themselves falling over the extension cord running to that one outlet in the room. Or start a fire by fraying that cord they have had tucked under the rug and have been walking over for 10 years. The spacing code has nothing to do with amperage tolerances. Just what I have experienced and have been told over many years of dealing with other folks' left-over properties.
Not to get everbody in a twist, but the point of designing a circuit and placing electrical outlets on that circuit is so that it rarely has to trip. That's why we break our basements up into several circuits, because we plan to draw a lot of amps into that room. Provide too many opportunites to trip a circuit, and the widow or Russian immigrant who occupies your property after you die will find a way to keep tripping it. If you have 12 outlets in a room on one circuit, regardless of how they are spaced, they will trip it. Codes are written in a fairly prescriptive manner and don't always capture the intent behind the code. Inspectors enforce the written code and have no method of enforcing the intent.
As has been said, the 12 foot spacing has to do with running cords all over the place within the room itself. It's so that widow or a future stroke victim doesn't kill themselves falling over the extension cord running to that one outlet in the room. Or start a fire by fraying that cord they have had tucked under the rug and have been walking over for 10 years. The spacing code has nothing to do with amperage tolerances.
Just what I have experienced and have been told over many years of dealing with other folks' left-over properties.
In kichens the code requires 20 amp circuits (which usually only have 15 amp outlets) and requires that outlets be on alternating circuits as we move "down" the counter.
In other words a kitchen counter with six outlets from left to right, would be arranged so that the first is on circuit A, the next on circuit B, the next on circuit C, the next back on circuit A, etc.
This is done to spread out the load over the required circuits just as you suggest.
But, to do this to all general outlets, throught the whole property would have several problems.
The first is cost.....
The second is that the code requires circuits to be identified in the panel, "master bedroom", "hall bath", "water heater" (it is not a hot water heater), etc, etc.
This task would become complex and expensive beyond all practicality if circuits were randomized, and that would still not insure trouble free operation.
As Randy said, that is what circuit breakers are for......
A better solution is to over build like I did in my 1901 Queen Anne, using one 20 amp circuit to handle general outlets for only 400 to 500 sq ft, rather than the code legal 800 sq ft.
I don't know anything about Russian immigrants or what that has to do with anything, but a well wired house works fine, and a poorly or outdated one does not. I've rewired more than few a 100 years old and older..........
And brought a lot of ones from the 40's, 50's, 60's and 70's up to current standards......none of them have burned down........
Sheldon
- Douglas
richhotrain Thanks for that info, Sheldon. One more question. When you use 15 amp outlets on 20 amp circuits, is the wire 12 gauge throughout the circuit? Rich
Thanks for that info, Sheldon. One more question. When you use 15 amp outlets on 20 amp circuits, is the wire 12 gauge throughout the circuit?
Rich
Yes, the entire circuit must be #12 wire.
Oh - no progress today, they just brought the electrical supplies, stair treads (the platform is getting removed and the stairs made straight - the horses are still in place, but the old treads were cut short so they can't be reused. ANd a small pile of additional wood for the center wall.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
True, you can't plug a 20 amp appliance into a 15 amp outlet - but you can put one of those 2 to 6 outlet adapters on the 15 amp outlet and plug in 3 things that draw 5 amps each plus another that draws 3 amps. ANd it won't trip the breaker because it's only an 18 amp load - in a 15 amp outlet.
Yeah, needs some effort on the point of the idiot doing this, but it can happen. I try to avoid such things, but don't look behind my computer desk... thing is, it's like 10 things plugged in, but most of them draw half an amp tops.
Alton Junction
richhotrain ATLANTIC CENTRAL richhotrain In spite of the that 15 amp outlets are allowed on 20 amp circuits, why not just use 15 amp outlets on 15 amp circuits and 20 amp outlets on 20 amp circuits? Rich Rich, Example, my big Victorian house is wired with all 20 amp circuits, not because I want to plug in any 20 amp appliances in the bed rooms, but so that less circuits can be used to cover the sq footage of the house at the required 3 VA per sq ft. 20 amp outlets have the "T" for the one prong, and have heavier contacts inside. Some people actually object to the appearance and the extra effort sometimes needed to plug into a 20 amp outlet. Sheldon Sheldon, do you have 15 amp outlets throughout the house? Rich
ATLANTIC CENTRAL richhotrain In spite of the that 15 amp outlets are allowed on 20 amp circuits, why not just use 15 amp outlets on 15 amp circuits and 20 amp outlets on 20 amp circuits? Rich Rich, Example, my big Victorian house is wired with all 20 amp circuits, not because I want to plug in any 20 amp appliances in the bed rooms, but so that less circuits can be used to cover the sq footage of the house at the required 3 VA per sq ft. 20 amp outlets have the "T" for the one prong, and have heavier contacts inside. Some people actually object to the appearance and the extra effort sometimes needed to plug into a 20 amp outlet. Sheldon
richhotrain In spite of the that 15 amp outlets are allowed on 20 amp circuits, why not just use 15 amp outlets on 15 amp circuits and 20 amp outlets on 20 amp circuits? Rich
In spite of the that 15 amp outlets are allowed on 20 amp circuits, why not just use 15 amp outlets on 15 amp circuits and 20 amp outlets on 20 amp circuits?
Rich,
Example, my big Victorian house is wired with all 20 amp circuits, not because I want to plug in any 20 amp appliances in the bed rooms, but so that less circuits can be used to cover the sq footage of the house at the required 3 VA per sq ft.
20 amp outlets have the "T" for the one prong, and have heavier contacts inside. Some people actually object to the appearance and the extra effort sometimes needed to plug into a 20 amp outlet.
Sheldon, do you have 15 amp outlets throughout the house?
Yes, except where code requires 20 amp, like the refrigerator circuit. Or where there was some expectation of pluging in a 20 amp piece of equipment with that special plug.
But, I also used all heavy duty side clamp commercial grade outlets and switches.
With receptacles the rating has little or nothing to do with how much current the parts inside can carry, it has everything to do with limiting or requiring what gets pluged in.
You can't plug in that 20 amp appliance without a 20 amp receptacle, which we hope is correctly on #12 wire and a 20 amp breaker.
If you have 15 amp receptacles, you can only plug in 15 amp stuff, on that circuit that may be 20 amps, or may be 15 amps, but could be serving several other rooms....
My Victorian is seriously over wired. One 20 amp circuit typically covers two rooms, which are as much as 250 sq ft each in many cases.
Additionally as required by the code, each bath has its own 20 amp circuit.
rrinker Train rooms, and maybe some other hobbies as well, tend to throw a wrench in everything. I'm sure I have way too many outlets in my plan, basically every 6 feet. But, with plenty of outlets, I will have no reason to use multi-way taps or long power strips I am kind of surprised at that loophole of allowing 15 amp outlets on 20 amp circuits. That makes a potentially dangerous assumption that by having more than one outlet on the circuit, the full load would never be applied through a single outlet. The other provisions (or lack thereof) are generally self-protecting, like no limit on number of outlets on a circuit. But a 15 amp outlet on a 20 amp circuit allows for the chance of overloading and overheating that outlet. Granted, not likely if that circuit is supplying multiple rooms, but the fact that the ability is there - and even without the use of splitters or power strips. Unless I'm missing a corresponding requirement that even 15 amp outlets need to be able to withstand a higher current, although I'd be amazed if the typical cheap crappy ones I've found in every home I lived in can truly handle 15 amps, let alone any sort of surge over that. Your one outlet in the center of each wall describes exactly how my house is set up. That's another reason I am running two more just to power my workbench upstairs. --Randy
Train rooms, and maybe some other hobbies as well, tend to throw a wrench in everything. I'm sure I have way too many outlets in my plan, basically every 6 feet. But, with plenty of outlets, I will have no reason to use multi-way taps or long power strips
I am kind of surprised at that loophole of allowing 15 amp outlets on 20 amp circuits. That makes a potentially dangerous assumption that by having more than one outlet on the circuit, the full load would never be applied through a single outlet. The other provisions (or lack thereof) are generally self-protecting, like no limit on number of outlets on a circuit. But a 15 amp outlet on a 20 amp circuit allows for the chance of overloading and overheating that outlet. Granted, not likely if that circuit is supplying multiple rooms, but the fact that the ability is there - and even without the use of splitters or power strips.
Unless I'm missing a corresponding requirement that even 15 amp outlets need to be able to withstand a higher current, although I'd be amazed if the typical cheap crappy ones I've found in every home I lived in can truly handle 15 amps, let alone any sort of surge over that.
Your one outlet in the center of each wall describes exactly how my house is set up. That's another reason I am running two more just to power my workbench upstairs.
Randy,
The side wiring straps on a 15 amp outlet are rated for 20 amps. So as part of the feed wiring it is fine. But the outlet limits the device pluged in to 15 amps.
15 amp outlets are allowed on 20 amp circuits as an extension of the various "tap rules".
Since an appliance that draws over 15 amps will have a 20 amp plug, it won't plug into a 15 amp outlet. The one prong in turned 90 degrees.........
Your frig draws less than 15 amps, has a 15 amp plug, but the code still wants you to install a 20 amp circuit and outlet, in case you buy some expensive semi commercial thing, and to keep that startup surge on a bigger breaker and wire.
mrrdad Doughless The more in a utilitarian space, or train room, the better, IMO. Normally I would agree. In our son's small 11'x12' bedroom, there are 9 outlets. Two weekends ago I replaced every outlet and cover plate in that room. At one point I remember saying " how many dang outlets did they need in here?!" Anyway, It's fun following along on build projects like this. I often pick up an idea or two. Thanks for sharing. Ed
Doughless The more in a utilitarian space, or train room, the better, IMO.
The more in a utilitarian space, or train room, the better, IMO.
Normally I would agree. In our son's small 11'x12' bedroom, there are 9 outlets. Two weekends ago I replaced every outlet and cover plate in that room. At one point I remember saying " how many dang outlets did they need in here?!"
Anyway,
It's fun following along on build projects like this. I often pick up an idea or two.
Thanks for sharing.
Ed
As an electrician who does historic restoration work and custom remodeling, 9 seems right for a bedroom that size depending on window and door locations.
I hate bedrooms with just one outlet in the middle of each major wall. you need the near thre corners, wher nite stands and dressers end up being placed.
rrinker Mainly because it doesn't matter how many outlets are on one circuit - you technically can't overload it. Plug too many things in, and the breaker will trip. Assuming the right value breaker, the proper size wire, and the proper receptacles are used. Even doing something dumb like putting a 20 amp outlet on a 15 amp branch circuit - well, if you try to actually use a 20 amp device, the breaker will trip. --Randy
Mainly because it doesn't matter how many outlets are on one circuit - you technically can't overload it. Plug too many things in, and the breaker will trip. Assuming the right value breaker, the proper size wire, and the proper receptacles are used. Even doing something dumb like putting a 20 amp outlet on a 15 amp branch circuit - well, if you try to actually use a 20 amp device, the breaker will trip.
Exactly.........
Trivia - where did the "every 12' thing" come from?
Answer - how long is your lamp cord? Generally they are 6'. So in theory you can put the lamp anywhere along the wall and reach the plug.......
By the way Randy, the basement looks great!
Doughless My point was not that the number of outlets causes amperage draw. It's that the number of outlets provides opportunities to plug in more things that the circuit could handle, even though each outlet can handle what has been plugged into it. Too many outlets in a given square footage, on one circuit, can be a hazard because the next person who buys the house doesn't know all of those outlets are wired into only one circuit. Or we may not know it when we become senile. 12 feet apart in a big room is too wide for convenience. 4 feet apart in a big room too close together resulting in too many outlets for one circuit to be safe, so we should break up the circuit into multiple circuits. 8 feet and 6 feet apart on one circuit seems like a happy medium, depending upon the size of the room. Just to be clear, as a member of the banking industry who has had the responsibility of owning houses other people left behind (treating it like it was their god given property despite having a mortgage owed to someone else, or right up until the point in their life they want someone else to buy it), I'm not just a weekend homeowner when it comes to understanding building techniques. I didn't do it much myself, but I had to police what others did on our behalf.
My point was not that the number of outlets causes amperage draw. It's that the number of outlets provides opportunities to plug in more things that the circuit could handle, even though each outlet can handle what has been plugged into it.
Too many outlets in a given square footage, on one circuit, can be a hazard because the next person who buys the house doesn't know all of those outlets are wired into only one circuit. Or we may not know it when we become senile.
12 feet apart in a big room is too wide for convenience. 4 feet apart in a big room too close together resulting in too many outlets for one circuit to be safe, so we should break up the circuit into multiple circuits. 8 feet and 6 feet apart on one circuit seems like a happy medium, depending upon the size of the room.
Just to be clear, as a member of the banking industry who has had the responsibility of owning houses other people left behind (treating it like it was their god given property despite having a mortgage owed to someone else, or right up until the point in their life they want someone else to buy it), I'm not just a weekend homeowner when it comes to understanding building techniques. I didn't do it much myself, but I had to police what others did on our behalf.
Despite what you think is common sense, the code makes no such restrictions.
I know and respect your knowledge, we have talked about that before.
I have been an Electrical Designer Draftsman and Electrician for 40 years, project managed the wiring of factories, sky scrapers, bridges, power plants, and houses........
And work with my tools every day in the building trades, and deal with the inspectors who enforce the codes........
In 40 years no inspector has ever told me we put in too many outlets, or had too many on one circuit.......because they went to code class too.........
Doughless riogrande5761 Doughless Installing outlets at this point costs very little. The more in a utilitarian space, or train room, the better, IMO. BTW, see how nice floor to ceiling sky blue walls look, As for outlets, I think where I live, they have to be no more that 12 linear feet apart but I put them more like 8 feet apart or maybe less. I was surprised that so few breakers run the upstairs. I went a bit overboard and have two separate 15 amp circuits for the back wall in the train room, and a 3rd circuit for the room with the walkout doors. A fourth circuit (20 amp) for the bathoom outlets. The ceiling lights are on their own too. I think the typical building code is for that 12 foot maximum between outlets in a finished wall. There is also a distinction if its living space or non living space, for rooms like laundry rooms, walk in closets, and in my case, basement garages. I could finish my garage and not put in more than one outlet if I wanted. Not sure how the law can judge all basements to be living space. An 8ft spread seems reasonable, maybe could go a little tighter. I think there could be overkill too, if you had 27 outlets crammed into a space, builders might fear someone would use all 27 outlets at once with 54 appliances, thereby overloading the circuit. So there has to be some balance between spacing of the outlets and the number of outlets on a circuit just to keep things safe for when dimensia sets in.....
riogrande5761 Doughless Installing outlets at this point costs very little. The more in a utilitarian space, or train room, the better, IMO. BTW, see how nice floor to ceiling sky blue walls look, As for outlets, I think where I live, they have to be no more that 12 linear feet apart but I put them more like 8 feet apart or maybe less. I was surprised that so few breakers run the upstairs. I went a bit overboard and have two separate 15 amp circuits for the back wall in the train room, and a 3rd circuit for the room with the walkout doors. A fourth circuit (20 amp) for the bathoom outlets. The ceiling lights are on their own too.
Doughless Installing outlets at this point costs very little. The more in a utilitarian space, or train room, the better, IMO. BTW, see how nice floor to ceiling sky blue walls look,
Installing outlets at this point costs very little. The more in a utilitarian space, or train room, the better, IMO.
BTW, see how nice floor to ceiling sky blue walls look,
As for outlets, I think where I live, they have to be no more that 12 linear feet apart but I put them more like 8 feet apart or maybe less. I was surprised that so few breakers run the upstairs. I went a bit overboard and have two separate 15 amp circuits for the back wall in the train room, and a 3rd circuit for the room with the walkout doors. A fourth circuit (20 amp) for the bathoom outlets. The ceiling lights are on their own too.
I think the typical building code is for that 12 foot maximum between outlets in a finished wall. There is also a distinction if its living space or non living space, for rooms like laundry rooms, walk in closets, and in my case, basement garages.
I could finish my garage and not put in more than one outlet if I wanted. Not sure how the law can judge all basements to be living space.
An 8ft spread seems reasonable, maybe could go a little tighter.
I think there could be overkill too, if you had 27 outlets crammed into a space, builders might fear someone would use all 27 outlets at once with 54 appliances, thereby overloading the circuit.
So there has to be some balance between spacing of the outlets and the number of outlets on a circuit just to keep things safe for when dimensia sets in.....
A few thoughts and fact from the National Electric code.....
Some local codes adjust the NEC to their wants, but generally in the US all wiring is governed by the single National Electric Code.
If you put drywall, flooring and a finished ceiling in a basement, the IRC (International Residential Code - the common building code in use in the US) and the NEC will consider it "living space".
There are lots of rules about where outlets need to be, and generally the 12' thing is the correct minimum requirement for general living areas. Closer is better.
But there are no restrictions on how many, or how close.
15amp vs 20amp - the code makes not requirement as to minimum or maximum number of outlets on a circuit past the first one. It says the building general receptacle load shall be served by at least 3VA per sq ft.
15 amps x 120 volts = 1800 VA / 3 = 600 sq ft.
20 amps x 120 volts = 2400 VA / 3 = 800 sq ft. (although as a designer I like to limit that to 750 sq ft)
Additionally, 20 amp circuits, wired with #12 wire, can use 15 amp outlets - as long as there are two or more outlets.
A 20 amp circuit feeding only one outlet, requires a 20 amp outlet, like your frig or washer.
So you can have 27 outlets on a 15 amp circuit if you want.........or logistics make it desired.
riogrande5761 I figured folks would come in and tell me should'a done 20 am circuits all the way around. Too late, basement is finished. But I know this forum is full of Tim Allens too so taking it all with a box car of salt. I did the math and should be ok. Heck, there are only 4 two plug outlets on one of those 15 amp circuits and 3 two plug and one 4 plug outlets on the other 15 amp circuit. If I could have done each of those as 20 amp, the electrician might have said really? LOL. The 3rd branch to the "wife-den" has 5 two plug outlets on it. This is way way more conservative than the circuits to the upstairs! Then there is a 20 amp to the bathroom that only feeds the bathroom plug outlet, apparently to allow for power sucking blow dryers. I ran a second outlet off of it to the utility room wall on the other side for the train work bench. The finished basement has way more capacity than the main and upper levels in the house. By my count, the train room has 10 separate outlets on 3 different circuits. It appears I'll get by some how.
I figured folks would come in and tell me should'a done 20 am circuits all the way around. Too late, basement is finished. But I know this forum is full of Tim Allens too so taking it all with a box car of salt. I did the math and should be ok.
Heck, there are only 4 two plug outlets on one of those 15 amp circuits and 3 two plug and one 4 plug outlets on the other 15 amp circuit. If I could have done each of those as 20 amp, the electrician might have said really? LOL. The 3rd branch to the "wife-den" has 5 two plug outlets on it. This is way way more conservative than the circuits to the upstairs!
Then there is a 20 amp to the bathroom that only feeds the bathroom plug outlet, apparently to allow for power sucking blow dryers. I ran a second outlet off of it to the utility room wall on the other side for the train work bench.
The finished basement has way more capacity than the main and upper levels in the house.
By my count, the train room has 10 separate outlets on 3 different circuits. It appears I'll get by some how.
Yes that is more than adequate.
Receptacle requirements in the code are based on square footage and special useage. A 15 amp circuit can handle the general receptacle needs of 600 sq ft, a 20 amp circuit handles 750 sq ft.
It does not matter how many outlets are on the circuit.
I feel like you're upset and some of that is directed at me since mine was the last comment. I was simply explaining what I have learned about the number of outlets relative to circuit capacity, and while its convenient to have a lot of outlets, it also it matters to not overload circuits with a bunch of outlets for convenience. I certainly didn't suggest you should have done anything differently. No worries, hopefully.
riogrande5761 I did the math and should be ok.
.
I am sure you will, You should have plenty of current capacity.
-Kevin
Living the dream.
Rio Grande. The Action Road - Focus 1977-1983
I have plenty of breaker slots, so it made snese to divide it all up - when I redid the kitchen, I took out an electric stve and a separate wall oven, so that was two double breakers for 240 that got removed. The gas range needs 120, so I ran 120 there, on a dedicated circuit. Where the wall oven was, I put in a shelf to hold a microwave, and changed that outlet to a 120, also on a dedicated breaker.
In the basement demo, I found out that the kitchen outlet circuit also feeds the lights for two of the sections of the basement - the two with the cans around the perimeter. It makes no sense, of all the palces they could have pulled power from - the other side has a total of three dual lamp flourescent fixtures on the entire circuit, they could have easily tapped off that without overloading anything. But nothing really is surprising me about this place any more.
rrinker SNuck that in while I was writing my book - on the subject of electric, I probably went way overboard. I have set it up for two 20 amp circuits for the basement outlets, plus the lights on another circuit (the overheads, not the layout lighting, that gets plugged in to the outlets). The old circuit for the basement outlets was a single 15 amp, the only thing that's going to be left on that one is the outlet for the washer/dryer and an outlet in the bathroom. I'm also installing some extra upstairs in the office/workshop room. Half the upstairs is all on one 15 amp circuit, and I already have 4 computers and a laser printer just in the one room. Since I had a subpanel installed int he finished side of the basement, it's easy to run wires up there, and I was putting in another pair of 20 amp circuits, one for my computers, and another for my electronic and hobby workbench - also probably way overkill. --Randy
SNuck that in while I was writing my book - on the subject of electric, I probably went way overboard. I have set it up for two 20 amp circuits for the basement outlets, plus the lights on another circuit (the overheads, not the layout lighting, that gets plugged in to the outlets). The old circuit for the basement outlets was a single 15 amp, the only thing that's going to be left on that one is the outlet for the washer/dryer and an outlet in the bathroom.
I'm also installing some extra upstairs in the office/workshop room. Half the upstairs is all on one 15 amp circuit, and I already have 4 computers and a laser printer just in the one room. Since I had a subpanel installed int he finished side of the basement, it's easy to run wires up there, and I was putting in another pair of 20 amp circuits, one for my computers, and another for my electronic and hobby workbench - also probably way overkill.
When we built our new home in 1999, the unfinished basement had one 15 amp circuit. I immediately added a second 15 amp circuit and divide the basement into the "East" portion and the " West" portion. My entire layout now runs off the East 15 amp circuit.
Our kitchen had separate 15 amp circuits for the stove and refrigerator and one more 15 amp circuit (controlling 4 duplex outlets) on the long counter wall below the cabinets. When we added a microwave above the stove, I converted the 15 amp stove circuit to a 20 amp stove/microwave circuit. Later, I added two more 20 amp circuits on the long counter wall so that a pair of duplex outlets shared each new 20 amp circuit. That ended the tripped circuit breaker scenario caused when the countertop oven and the pancake griddle were all plugged in.
riogrande5761I wondered if I shouldn't have gone with 20 amp circuits
My electrician said the cost between 15 and 20 amp components is so minimal that it did not make sense to choose a 15 amp circuit for the layout, even if expected current draw is under 5 amps.
My train room will have 2 dedicated 20 amp circuits in addtion to the wiring tha is already there. One for the layout and one for the workbench.
I wondered if I shouldn't have gone with 20 amp circuits for my left and right branches in the trainroom, but since the only things using those two circuits will be the layout, I hope it will be ok. I'd think the main thing using those two circuits will be DCC boosters. There are sockets on different circuits on the opposite wall that other things could use.
The 20 amp bathroom circuit has an extra 4 socket outlet run into the unfinished utility "shop" room where I have a work bench and plan for a paint booth eventually.
So my basment basically has 3 separate 15 amp wall outlet circuits (to the main rooms) and a 20 amp wall outlet circuit (bathroom) to the newly finished area, as well as other outlets on other circuits pre-dating the finishing.