Aluminium house wiring

[zahc]

Any opinions on houses that have aluminium wiring?

I heard that the receptacles and switches can be pigtailed with copper, using some special crimp that cold-welds the copper and aluminium together, but that sounds like a lot of work. Now I've heard another theory that the pigtailing can be done with wire nuts as long as you use a special kind of grease to prevent corrosion. Still a lot of work.

Lots of 70s-era houses around here have it. 

[zxcvbob]

Nothing wrong with big aluminum wire if it's terminated correctly.  #14 and #12 Aluminum wire sucks, but you can work with it -- use purple wirenuts to pigtail it with copper, or use new CO/ALR rated devices.  (the cost is about the same either way; purple wire nuts are expensive and you'd need several per device.  DO NOT use devices smaller than 30A that are listed CU/AL, that was the problem in the 70's more-so than the wire.

Whichever route I took, I would put that black goop on all the connections unless the connector specifically said not to use it.

[AJ Dual]

I should start a business that prints up signs for construction and remodeling sites that says,

"THIS HOUSE IS WIRED WITH ALUMINUM, AND PIPED WITH PEX AND PVC. THERE IS NO COPPER."

Maybe make some sort of pictoral representation to go with it for sub-literate crackheads/methheads. 

Either that, or we need to figure out a two-pronged approach to electrify unattended house and construction wiring and pipes to lethal levels for theft-proofing from a technology side, and making that legal from a .gov side...

[geronimotwo]

sorry, al wiring sucks.  having worked on a few homes with it, invariably every screw terminal is loose.  if i do any wiring related work in those homes i will have the occupants sign a statement that they have been informed that their house is a death trap.  there is a reason why it is not used for anything but large conductors anymore, and every terminal of that is coated with "contax" non-corroding goop.

[charby]

I should start a business that prints up signs for construction and remodeling sites that says,

"THIS HOUSE IS WIRED WITH ALUMINUM, AND PIPED WITH PEX AND PVC. THERE IS NO COPPER."

Maybe make some sort of pictoral representation to go with it for sub-literate crackheads/methheads. 

Either that, or we need to figure out a two-pronged approach to electrify unattended house and construction wiring and pipes to lethal levels for theft-proofing from a technology side, and making that legal from a .gov side...

Painting copper pipes white or black deters many a copper thief.

[lee n. field]

Any opinions on houses that have aluminium wiring?

I heard that the receptacles and switches can be pigtailed with copper, using some special crimp that cold-welds the copper and aluminium together, but that sounds like a lot of work. Now I've heard another theory that the pigtailing can be done with wire nuts as long as you use a special kind of grease to prevent corrosion. Still a lot of work.

Lots of 70s-era houses around here have it. 

My recollection is also that there was a special grease that was supposed to be used for Al to Cu connections.  Supposed to be.

Aluminum wire was also a big problem in mobile homes of that era.

[Scout26]

Re-wire with copper.  The problem is that Aluminum expands and contracts as it's used (heated up), that causes the contacts to expand and contract and eventually you get sparking and shorts, hence fires.


Pull the aluminum wire and re-wire with copper.

[zahc]

Does anyone have the context to guesstimate how much wire for a 1700sq ft single-story?

I can wire, but I'm guessing that running new wire down the walls is not going to be fun with a low-pitched roof. Pigtailing all the outlets sounds more attractive since it can be done in the AC.

[charby]

Does anyone have the context to guesstimate how much wire for a 1700sq ft single-story?

I can wire, but I'm guessing that running new wire down the walls is not going to be fun with a low-pitched roof. Pigtailing all the outlets sounds more attractive since it can be done in the AC.

Got a basement?

[lee n. field]

Got a basement?

That's my first thought -- dead easy if you have a basement or crawlspace with enough room to get to the floor from underneath.

[zahc]

I live in Texas, where people think it's utterly normal to build a house with no foundation.

And no, a slab poured on top of the dirt is not a "foundation".

[Tallpine]

Does anyone have the context to guesstimate how much wire for a 1700sq ft single-story?

I can wire, but I'm guessing that running new wire down the walls is not going to be fun with a low-pitched roof. Pigtailing all the outlets sounds more attractive since it can be done in the AC.

You conduit 

[charby]

Does anyone have the context to guesstimate how much wire for a 1700sq ft single-story?

Figure out how many outlets you have and the average the distances from the e-panel. Figure double distance for lights or triple if they are on a 3-way circuit.

I bet somewhere around 2000'-2500' feet of romex.

[geronimotwo]

^^^^^when calculating, remember that many outlets are connected together, rather than going back to the main panel. 

[Balog]

And while it may seem like a good idea to save wire by extensive daisy chaining, mo circuits is mo better.

[CNYCacher]

You conduit 

This is your opus.

[zahc]

http://www.homedepot.com/p/Cerrowire-250-ft-14-2-NM-B-Wire-147-1472G/202304609#.UdMuqpxCjLs

So it would only be about $300 or so for the wire. Sounds like a fun weekend project.

[Balog]

Consider at least a couple 12/2 20amp circuits for the kitchen.

[CNYCacher]

Do 12/2 anyway.  Even if you are not going to run 20-amp breakers and receptacles.  You'll have less high-load brownout and upgrading to 20 later will be easy. One-time chance.

[charby]

Do 12/2 anyway.  Even if you are not going to run 20-amp breakers and receptacles.  You'll have less high-load brownout and upgrading to 20 later will be easy. One-time chance.

x1000000000

[zahc]

I know the kitchen needs 2 dedicated 20-amp circuits. But 12-2 is $62 vs $41 a roll. As far as I know, code frowns on running 12 gage wire and then wiring up 15-amp receptacles, and 20-amp receptacles are also more expensive than 15-amp ones. And dealing with the wire in junction boxes is a pain, with more volume needed per wire running through per box-size requirements. I know, because I wired up my darkroom with 12-gage wire "just in case".  Everything kind of multiplies.

[CNYCacher]

As far as I know, code frowns on running 12 gage wire and then wiring up 15-amp receptacles

Only if you are combining it with 20-amp breakers.

You can do the entire house in 12/2 and as long as you use 15-amp breakers, 15-amp receptacles are fine.

How big are the rolls you are pricing? I bet the cost difference is less somewhat in bulk.

[zahc]

The largest rolls Home Depot sells are 250 feet.

[zxcvbob]

Are the lighting circuits separate already from the outlets?  If so you might just leave them AL, they don't have the current load and resultant heating/contracting that loosens the connections.  At least prioritize the kitchen circuits, bathrooms, laundry rooms, and other convenience outlets higher.

[zxcvbob]

I know the kitchen needs 2 dedicated 20-amp circuits. But 12-2 is $62 vs $41 a roll. As far as I know, code frowns on running 12 gage wire and then wiring up 15-amp receptacles, and 20-amp receptacles are also more expensive than 15-amp ones. And dealing with the wire in junction boxes is a pain, with more volume needed per wire running through per box-size requirements. I know, because I wired up my darkroom with 12-gage wire "just in case".  Everything kind of multiplies.

No it doesn't.  You can even put 15A duplex receptacles on a 20A circuit.