You don't necessarily need the tube unless the wire doesn't want to cooperate
and go through to the inside. A coathanger can fix that.

When you seal the tube to the outside siding or whatever, you are still sealing
to the outside layer. The compromise to the "R" factor of the wall is very
small as long as it's sealed with RTV.

Using the tube, however, results in a more professional looking job, if you
want to retain all of the "R" value you should find a way to use silicone all
the way down the tube, or somehow maybe that expanding foam stuff.

More importantly, make sure you know how and put a drip loop in it. This is all
in which way you staple the wire, do it so the wire ultimately comes Uup/U
to the hole, tube or not. I'm sure there are examples on the net somewhere or
something. Basically all forms of sealant eventually fail, and with a drip loop
you get 10 years before there's a problem instead of 2, as long as you keep
that rain from running down the wire right into the hole. Then, gravity is your
friend .

My two cents, hmm lemme see, that's not even ¼ of a cigarette, hmm it's closer
to ¼ of a 12 oz. beer. Damn, I bet you could drink two cents worth of gasoline
these days without dying.

We are going to have to raise our rates, but don't worry about it.

JURB