I am having a sub panel put into an attached garage. It will be fed
from a 100 amp breaker in one of my house breaker panels. The wire run
will be about 100 feet thru crawlspace and connecting breezeway.

The electrician wants to use AWG 2 aluminum wire. I prefer copper but
know it is more expensive, especially with the recent copper price
rises. He is going to check on what the additional cost will be to go
to copper wire to the sub panel.

Can anyone provide me with a ballpark estimate of the cost of aluminum
versus copper wire for a 100 amp run over 100 feet?

PaulF

On Wed, 14 Jun 2006 13:48:07 -0400, wrote:

On Wed, 14 Jun 2006 17:31:13 GMT, Paul Ferguson
wrote:

The electrician wants to use AWG 2 aluminum wire.
He should be using #1al for 100a (NEC 310.16) or #2 cu (#3 cu if you
can get it).
There is really no compelling reason not to use aluminum if it is
sized properly.


Thanks. Maybe he is derating it for being a single dwelling. He says
local code allows no 2 Al.

He got the prices -- No. 2, 4 wire Al wire is $1.32/ft and No. 4, 4
wire copper is $4.82/ft.

I decided to go Al.

PaulF

When you say "wire" do you mean single conductor or are you referring to a
cable? I just purchased #4 THHN copper today for 1.25 per foot, for cut
wire. A roll of 500 ft was cheaper



"Paul Ferguson" wrote in message
...
On Wed, 14 Jun 2006 13:48:07 -0400, wrote:

On Wed, 14 Jun 2006 17:31:13 GMT, Paul Ferguson
wrote:

The electrician wants to use AWG 2 aluminum wire.
He should be using #1al for 100a (NEC 310.16) or #2 cu (#3 cu if you
can get it).
There is really no compelling reason not to use aluminum if it is
sized properly.


Thanks. Maybe he is derating it for being a single dwelling. He says
local code allows no 2 Al.

He got the prices -- No. 2, 4 wire Al wire is $1.32/ft and No. 4, 4
wire copper is $4.82/ft.

I decided to go Al.

PaulF

In article , wrote:
On Wed, 14 Jun 2006 17:31:13 GMT, Paul Ferguson
wrote:

The electrician wants to use AWG 2 aluminum wire.
He should be using #1al for 100a (NEC 310.16) or #2 cu (#3 cu if you
can get it).

Per NEC 310.16, with 90-deg C insulation (e.g. THHN) #2 Al is OK for 100A.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

I would go with copper since its a one time expense. 100 feet of
aluminimum will have a voltage drop, which YOU will pay for.

Personally I DONT care how much power the electrical supplier wastes
but do care if I am paying for it....

Besides if your doing something power hungry that drop might matter....

if the sub panel feed is underground put it in conduit in case you ever
decide to upgrade

In article . com, " wrote:
I would go with copper since its a one time expense. 100 feet of
aluminimum will have a voltage drop, which YOU will pay for.

So will 100 feet of copper; so what? The voltage drop in a _properly_sized_
aluminum conductor is not significantly different from the voltage drop in a
properly sized copper conductor.

Personally I DONT care how much power the electrical supplier wastes
but do care if I am paying for it....

You're paying for it anyway. You seem to be under the impression that copper
wire doesn't cause voltage drop. That is not correct.

Besides if your doing something power hungry that drop might matter....

Utter nonsense.

if the sub panel feed is underground put it in conduit in case you ever
decide to upgrade

First thing you've said in this post that makes sense.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

For LOTS of devices the last few volts can be the difference between
good operation and crappy use.

Lamps are like that, the last few volts is about 8% of the total
britness. I used to fix copiers for a living, slight voltage drops
caused major grief.

if your running a 120 volt moter it probably doesnt matter....

All conductors have voltage drop but alunimum is much worse than
copper.

cheapinbg out on a one time expense is poor planning...

Been there done stuff like that

my 100 amp main service is a memorable stupid move.

Sometimes cheaper isnt better

the price difference is under 300 bucks, for a one time lifetime
expense..

besides at resale a home inspection, and nervous buyer.... equal pain
in you know what.

I'm missing your point. When aluminum is used, the conductor size is
increased from what it would be if copper was used, so there shouldn't be
any significant difference in voltage drop


wrote in message
oups.com...

For LOTS of devices the last few volts can be the difference between
good operation and crappy use.

Lamps are like that, the last few volts is about 8% of the total
britness. I used to fix copiers for a living, slight voltage drops
caused major grief.

if your running a 120 volt moter it probably doesnt matter....

All conductors have voltage drop but alunimum is much worse than
copper.

cheapinbg out on a one time expense is poor planning...

Been there done stuff like that

my 100 amp main service is a memorable stupid move.

Sometimes cheaper isnt better

the price difference is under 300 bucks, for a one time lifetime
expense..

besides at resale a home inspection, and nervous buyer.... equal pain
in you know what.

On Wed, 14 Jun 2006 16:18:53 -0400, "RBM" rbm2(remove
wrote:

When you say "wire" do you mean single conductor or are you referring to a
cable? I just purchased #4 THHN copper today for 1.25 per foot, for cut
wire. A roll of 500 ft was cheaper


I did mean "cable" when I said "wire". The price quoted was for the
cable per foot.

PaulF

I see your point properly sized the voltage drop should be the
same......

my point is aluminum wire may be a issue at resale

copper isnt that much more, a few hundred on a fairly big job. If your
paying to have it done the install labor is likely a large cost, which
makes a few hundred as a percentage of the job, a minor issue...

I guess I just dont like anything but copper for wiring, its the ideal
product.

I certainly prefer to use copper, although I've never had problems with
aluminum in larger sizes. Right now with copper prices up around 600%, there
is a huge difference in price between the two. If the price doesn't come
down, I think alot of people are going to suddenly see aluminum in a
different light




wrote in message
oups.com...
I see your point properly sized the voltage drop should be the
same......

my point is aluminum wire may be a issue at resale

copper isnt that much more, a few hundred on a fairly big job. If your
paying to have it done the install labor is likely a large cost, which
makes a few hundred as a percentage of the job, a minor issue...

I guess I just dont like anything but copper for wiring, its the ideal
product.

wrote:
The world is filled with moron home inspectors

One of my pet peeves about giving someone a little authority and they
make their own rules.

Unless specifically mandated to prohibit use inspections should be
according to the rules in effect at time of construction or installation.



Example I sold a home lerss than 2 years ago. The first buyer backed
out after the inspection commenting your home is in terrible shape

This based on the inspection...

Written up:

No GFCI on sump pump in garage The home is 50 years old. GFCIs diodnt
exist when it was built. After buyer #1 backed out I installed GFCI...

Next buyers inspector. You have GFCI on sump pump VERY BAD!

Even the home inspectors couldnt agree....

so anything peculiar will bring questions and hassles............

Most people just know anything but copper is bad...

Even if it passes inspection that nagging doubt may cost you a buyer or
some bucks

Home inspectors want old houses built to 2010 standards, which is
impossible...

Its a dis service to everyone!

In article .com, " wrote:

All conductors have voltage drop but alunimum is much worse than
copper.

For the same size conductor, yes -- but you _don't_use_ the same size
conductors with aluminum that you do with copper.

The difference in voltage drop in a copper conductor sized for 100A, and an
aluminum conductor sized for 100A, is negligible.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.