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Oversized Wiring

Electricity is always best described as flowing water. My questions are; Would it be better to run a little bit bigger wirng than normal yet never using more than the required amount of electricity for an outlet or appliance? Less resistance so Electricty would flow more freely or efficiently and not be prone to build up dangerous heat? Other than cost what are disadvantages to this? Just curious..


Re: Oversized Wiring

I'm not sure about the "efficiency" concept but it would be true that using bigger wiring should keep from building excessive heat. However using the proper size wire shouldn't build much if any heat anyways. The only way you need to worry about excessive heat buildup to the point of worrying about fire is if you use wire that's pretty undersized. A good rule of thumb is 12ga wire for plug-ins and 14ga wire for lighting.

Re: Oversized Wiring

It's a cost benefit ratio thing. Properly sized wiring with proper current protection will not over heat. Code has a better than 20% safety margin built into it.

A 4" fire hose will deliver water to your garden with less resistance but it won't increase the amount of water available. It just costs more.

Re: Oversized Wiring

A 4" fire hose will deliver water to your garden with less resistance but it won't increase the amount of water available. It just costs more.

A great analogy. (But it would if it was hooked to a pumper truck....... Doubt there would be many roses or radishes left though. :D)

Box fill and wire size capacity would be quickly eaten up and trying to terminate larger guage wire on devices would be a nightmare.

Seems to me that the boys and girls at the NFPA have pretty much got the wire size thing figured out over the last 100 plus years and there seems no reason to me to reinvent the wheel.

Re: Oversized Wiring

these are all good points. umm no one mentioned the only thing you have to worry about when going bigger wire is box fill!! now putting in much bigger wire you are gonna have a lot harder time shoving everything back in the boxes. let alone code issues about box fill!! you might actually make the installion illegal buy going bigger.. the whole build up of heat is a good point. but like stated, thats all taken into account in the code..

Re: Oversized Wiring

under normal conditions, in a house...

BAD TERMINATIONS are more likely to produce excessive heat.

overloaded circuits withstanding.

Most areas of a house #14 is fine even for outlets IMO, now living room, kitchen, dining room, etc the 20 amp #12 requirements make perfect sense. 14 is good for all lighting circuits.

If you want to "over wire" it, your better served putting fewer devices on one circuit.

homerun all the gfi's

keep lighting seperate

put each room or pair of rooms on its /there own circuit, label it clearly

use 3 wire for all ceiling outlets and fan rated boxes

but as far as over sizing the wire it just complicates things the biggest being the dreaded wire fill

try putting two 4ways in one 2 gang box with 12 wire, they just dont make a plastic box big enough and your forced to use 1900 boxes and extension rings .. everything is harder your drilling bigger holes so you have to be carefull your right in the center of the stud or your gonna use more nail plates, the difference between wrapping 12 wire and 14 wire around screws all day is actually a big difference, splicing, alot of exaust fans dont have enough wire fill for 12/3, floor outlets (the single yoke round ones), etc etc

Its like walking your kitten on a tow chain.

Re: Oversized Wiring

Thanks everyone for there input thus far. Awesome stuff! I will certainly have lots more questions coming soon..

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