[John]

I'm redoing my basement and I have put in some of the rigid pink
insulation boards on the wall. So far, I've attached the boards to
the wall, and built a frame (1 1/2") on top of that. I'm planning on
putting more of the boards in between the framing studs before doing a
vapor barrier and dry-walling. My problem right now is that I want to
add an outlet near the bottom of one of the walls... So, I have to
run a wire through the wall to the electrical box...

I'm wondering if I should be doing anything special around the wire
and/or the electrical box when doing this.


John

[TWayne]

In ,
John typed:
I'm redoing my basement and I have put in some of the rigid
pink insulation boards on the wall. So far, I've attached
the boards to the wall, and built a frame (1 1/2") on top
of that. I'm planning on putting more of the boards in
between the framing studs before doing a vapor barrier and
dry-walling. My problem right now is that I want to add an
outlet near the bottom of one of the walls... So, I have
to run a wire through the wall to the electrical box...

I'm wondering if I should be doing anything special around
the wire and/or the electrical box when doing this.


John

Just don't let the wires be insulated by the pink board. Wire temps are
derated at ambient room temps. Insulation will collect/keep the heat in.

[Borrall Wonnell[_2_]]

On Oct 25, 2:25*pm, "Twayne" wrote:
,
John typed:

I'm redoing my basement and I have put in some of the rigid
pink insulation boards on the wall. *So far, I've attached
the boards to the wall, and built a frame (1 1/2") on top
of that. *I'm planning on putting more of the boards in
between the framing studs before doing a vapor barrier and
dry-walling. *My problem right now is that I want to add an
outlet near the bottom of one of the walls... *So, I have
to run a wire through the wall to the electrical box...

I'm wondering if I should be doing anything special around
the wire and/or the electrical box when doing this.

John

Just don't let the wires be insulated by the pink board. Wire temps are
derated at ambient room temps. Insulation will collect/keep the heat in.

I didn't think you needed to derate cables in residential construction
unless you have bundles of cable. Around here, you are encouraged to
insulate as much as possible...no issues with insulating against
modern electrical cable. The exception would be if you had old-style
wiring (the type where the sheathing was prone to flake off over
time).

[Mikepier]

On Oct 25, 12:20*pm, John wrote:
I'm redoing my basement and I have put in some of the rigid pink
insulation boards on the wall. *So far, I've attached the boards to
the wall, and built a frame (1 1/2") on top of that. *I'm planning on
putting more of the boards in between the framing studs before doing a
vapor barrier and dry-walling. *My problem right now is that I want to
add an outlet near the bottom of one of the walls... *So, I have to
run a wire through the wall to the electrical box...

I'm wondering if I should be doing anything special around the wire
and/or the electrical box when doing this.

John

Just curious why are you using foam boards? You get a lot more R value
if you used the regular insulating fiberglass batts.

[RicodJour]

On Oct 25, 1:29*pm, Mikepier wrote:

Just curious why are you using foam boards? You get a lot more R value
if you used the regular insulating fiberglass batts.

Foam board acts as a continuous vapor barrier with no thermal "short
circuits" from the studs. Any time you calculate the actual
insulation value you always have to allow for the framing. A 2x4 has
an R value of ~1/inch, or 3.5, and the studs take up around ten or
fifteen percent of the wall.

The preferred method and amount of insulation is dependent on climate,
as well. You want to make sure that there's only one vapor barrier,
and you're not trapping moisture in between two vapor barriers. One
layer of foam, and either a stud wall with just drywall, or with
unfaced batt insulation between the joists (allowing the foundation
walls to dry to the interior) is preferable to two layers of foam.

http://www.diychatroom.com/f15/basem...barrier-10870/

R

[Borrall Wonnell[_2_]]

On Oct 25, 3:29*pm, Mikepier wrote:
On Oct 25, 12:20*pm, John wrote:
I'm wondering if I should be doing anything special around the wire
and/or the electrical box when doing this.

John

Just curious why are you using foam boards? You get a lot more R value
if you used the regular insulating fiberglass batts.

XPS foam (generally blue/pink) is superior to fiberglass batts in R-
value and also forms a pretty good vapour barrier if you're careful
with it. It doesn't absorb water, so putting it directly against
concrete walls seems like a great idea...any moisture will run down
the outside rather than rotting your studs. Assuming you have a place
for the water to go, that is. You've generally got to cover it with
a 15-minute fire barrier (1/2" drywall, plywood, etc.).

XPS offers about 30% - 45% more R-value per inch. Also costs quite a
bit more.

[John]

On Oct 25, 2:38*pm, Borrall Wonnell wrote:
On Oct 25, 3:29*pm, Mikepier wrote:

On Oct 25, 12:20*pm, John wrote:
I'm wondering if I should be doing anything special around the wire
and/or the electrical box when doing this.

John

Just curious why are you using foam boards? You get a lot more R value
if you used the regular insulating fiberglass batts.

XPS foam (generally blue/pink) is superior to fiberglass batts in R-
value and also forms a pretty good vapour barrier if you're careful
with it. *It doesn't absorb water, so putting it directly against
concrete walls seems like a great idea...any moisture will run down
the outside rather than rotting your studs. *Assuming you have a place
for the water to go, that is. * You've generally got to cover it with
a 15-minute fire barrier (1/2" drywall, plywood, etc.).

XPS offers about 30% - 45% more R-value per inch. *Also costs quite a
bit more.

Yes, I was originally going to do foam board, and then use vatting
between the studs, giving me an R-Value of around 19. But then the
wife found out I was going to go 6" into the room to do that, and,
after a bit of deliberation, we decided to do just 1 1/2" foam board,
and a 1 1/2" frame on top of that (Already bought the 2x4's, so I just
turned those sideways...). I would put the vat insulation between the
studs, but I didn't see any made for 1 1/2" (maybe I'll look again),
as the regular insulation is WAY cheaper. But yes, the foam board
does have a higher R-value per inch than vat, and has a much higher R-
value when you consider the 2x4's in your equation (the advertised R-
value on vat is the R value of the insulation, and does not take into
account the 2x4). As far as moisture, I'm not vapor-barring the space
between the floor and the insulation or the space above, so I figure
the water will have somewhere to go (and no, the frame is not resting
on the concrete floor, so I'm not scared of rot there).

I'm concerned about the wiring for the reason mentioned above -- do I
want to insulate a hot cable. While I expect the circuit breaker
would flip before the wire gets to the magic temperature, I don't want
to build something that has the potential to do some serious damage if
things went really wrong (say a nail shorted the wire and the breaker
didn't flip or something like that). I'm thinking maybe I'll cut a
channel in the foam, and put regular vat insulation in there, and run
the wire through that.


John

[RicodJour]

On Oct 25, 4:54*pm, John wrote:
On Oct 25, 2:38*pm, Borrall Wonnell wrote:



On Oct 25, 3:29*pm, Mikepier wrote:

On Oct 25, 12:20*pm, John wrote:
I'm wondering if I should be doing anything special around the wire
and/or the electrical box when doing this.

John

Just curious why are you using foam boards? You get a lot more R value
if you used the regular insulating fiberglass batts.

XPS foam (generally blue/pink) is superior to fiberglass batts in R-
value and also forms a pretty good vapour barrier if you're careful
with it. *It doesn't absorb water, so putting it directly against
concrete walls seems like a great idea...any moisture will run down
the outside rather than rotting your studs. *Assuming you have a place
for the water to go, that is. * You've generally got to cover it with
a 15-minute fire barrier (1/2" drywall, plywood, etc.).

XPS offers about 30% - 45% more R-value per inch. *Also costs quite a
bit more.

Yes, I was originally going to do foam board, and then use vatting
between the studs, giving me an R-Value of around 19. *But then the
wife found out I was going to go 6" into the room to do that, and,
after a bit of deliberation, we decided to do just 1 1/2" foam board,
and a 1 1/2" frame on top of that (Already bought the 2x4's, so I just
turned those sideways...). *I would put the vat insulation between the
studs, but I didn't see any made for 1 1/2" (maybe I'll look again),
as the regular insulation is WAY cheaper. *But yes, the foam board
does have a higher R-value per inch than vat, and has a much higher R-
value when you consider the 2x4's in your equation (the advertised R-
value on vat is the R value of the insulation, and does not take into
account the 2x4). *As far as moisture, I'm not vapor-barring the space
between the floor and the insulation or the space above, so I figure
the water will have somewhere to go (and no, the frame is not resting
on the concrete floor, so I'm not scared of rot there).

I'm concerned about the wiring for the reason mentioned above -- do I
want to insulate a hot cable. *While I expect the circuit breaker
would flip before the wire gets to the magic temperature, I don't want
to build something that has the potential to do some serious damage if
things went really wrong (say a nail shorted the wire and the breaker
didn't flip or something like that). *I'm thinking maybe I'll cut a
channel in the foam, and put regular vat insulation in there, and run
the wire through that.

It's called batt insulation, vat is what they keep the wine in while
you're installing the batts.

As far as worrying about insulating around wires...have you ever seen
an exterior wall that didn't have wires running through it? It's not
a problem, so don't worry about it.

R

[willshak]

Twayne wrote the following:
In ,
John typed:

I'm redoing my basement and I have put in some of the rigid
pink insulation boards on the wall. So far, I've attached
the boards to the wall, and built a frame (1 1/2") on top
of that. I'm planning on putting more of the boards in
between the framing studs before doing a vapor barrier and
dry-walling. My problem right now is that I want to add an
outlet near the bottom of one of the walls... So, I have
to run a wire through the wall to the electrical box...

I'm wondering if I should be doing anything special around
the wire and/or the electrical box when doing this.


John


Just don't let the wires be insulated by the pink board. Wire temps are
derated at ambient room temps. Insulation will collect/keep the heat in.

Wouldn't that apply to spray foam insulation too?

--

Bill
In Hamptonburgh, NY
In the original Orange County. Est. 1683
To email, remove the double zeroes after @

[TWayne]

....

I'm concerned about the wiring for the reason mentioned
above -- do I want to insulate a hot cable. While I expect
the circuit breaker would flip before the wire gets to the
magic temperature, I don't want to build something that has
the potential to do some serious damage if things went
really wrong (say a nail shorted the wire and the breaker
didn't flip or something like that). I'm thinking maybe
I'll cut a channel in the foam, and put regular vat
insulation in there, and run the wire through that.


John

Really, the right thing to do is check with your code enforcement office
since they get the last word on everything anyway. Also a few searches on
your favorite search engine can help, too. There is no one-size fits all
answer here. As soon as wire hits 75 to 80 % of its specs, ambient heat
buildup begins. Insulate that and of course the heat buildup increases if
the heat has no place to go. That's why you see all the splits & butt ups,
in residential rules.

Following is only one of many things that relate to this stuation. There
isn't just one answer.

======
- - - The ampacity of Types NM, NMC, and NMS cable shall be determined in
accordance with 310.15. The ampacity shall be in accordance with the 60°C
(140°F) conductor temperature rating. The 90°C (194°F) rating shall be
permitted to be used for ampacity derating purposes, provided the final
derated ampacity does not exceed that for a 60°C (140°F) rated conductor.
The ampacity of Types NM, NMC, and NMS cable installed in cable tray shall
be determined in accordance with 392.11.
- - - Where more than two NM cables containing two or more current-carrying
conductors are installed, without maintaining spacing between the cables,
through the same opening in wood framing that is to be fire- or
draft-stopped using thermal insulation, caulk, or sealing foam, the
allowable ampacity of each conductor shall be adjusted in accordance with
Table 310.15(B)(2)(a) and the provisions of 310.15(A)(2), Exception, shall
not apply.
- - - Where more than two NM cables containing two or more current-carrying
conductors are installed in contact with thermal insulation without
maintaining spacing between cables, the allowable ampacity of each conductor
shall be adjusted in accordance with Table 310.15(B)(2)(a).

Table 310.15.(B)(2)(a) is the derating table.

Thus, first there is the derating for ambient - which ALWAYS applies and
ALWAYS applies first (in severe cold climates, derating still "applies", it
is just that there is no derating "to apply"), then the derating for
bundling or lack of maintaining spacing applies, AND, if there is no
bundling or lack of maintaining spacing - which is what triggers Table
310.15(B)(2)(a) in 334.80 Ampacity - then there is no harm and no foul.

This tells me that they ran tests and determined that, as long as the cables
are spaced out, they are suitable for the same ampacity in thermal
insulation. That is because the NM-B uses 90 degree C rated insulation,
which apparently can withstand the accumulated heat of normal allowable
current flow within the conductor. The normal allowable current flow in a
#12 is 20 amps overcurrent protection, with normal less than 80% on the
circuit if a continuous load, if not a continuous then there will not be the
same heat build-up to be concerned with.
__________________
==========

HTH,

Twayne`

[TWayne]

In m,
willshak typed:
Twayne wrote the following:
In
,
John typed:
I'm redoing my basement and I have put in some of the
rigid pink insulation boards on the wall. So far, I've
attached the boards to the wall, and built a frame (1
1/2") on top of that. I'm planning on putting more of
the boards in between the framing studs before doing a
vapor barrier and dry-walling. My problem right now is
that I want to add an outlet near the bottom of one of
the walls... So, I have to run a wire through the wall
to the electrical box... I'm wondering if I should be doing anything
special around
the wire and/or the electrical box when doing this.


John


Just don't let the wires be insulated by the pink board.
Wire temps are derated at ambient room temps. Insulation
will collect/keep the heat in.

Wouldn't that apply to spray foam insulation too?

Yes. That's why you see in the regs to split the foam and butt it, rather
than just let it all be insulated; the heat needs a place to dissipate to.
See previous post for some references instead of just words of opinion.

[RicodJour]

On Oct 26, 3:03*pm, "Twayne" wrote:
...

I'm concerned about the wiring for the reason mentioned
above -- do I want to insulate a hot cable. *While I expect
the circuit breaker would flip before the wire gets to the
magic temperature, I don't want to build something that has
the potential to do some serious damage if things went
really wrong (say a nail shorted the wire and the breaker
didn't flip or something like that). *I'm thinking maybe
I'll cut a channel in the foam, and put regular vat
insulation in there, and run the wire through that.

John

Really, the right thing to do is check with your code enforcement office
since they get the last word on everything anyway. Also a few searches on
your favorite search engine can help, too. There is no one-size fits all
answer here. As soon as wire hits 75 to 80 % of its specs, ambient heat
buildup begins. Insulate that and of course the heat buildup increases if
the heat has no place to go. That's why you see all the splits & butt ups,
in residential rules.

Following is only one of many things that relate to this stuation. There
isn't just one answer.

======
- - - The ampacity of Types NM, NMC, and NMS cable shall be determined in
accordance with 310.15. The ampacity shall be in accordance with the 60°C
(140°F) conductor temperature rating. The 90°C (194°F) rating shall be
permitted to be used for ampacity derating purposes, provided the final
derated ampacity does not exceed that for a 60°C (140°F) rated conductor.
The ampacity of Types NM, NMC, and NMS cable installed in cable tray shall
be determined in accordance with 392.11.
- - - Where more than two NM cables containing two or more current-carrying
conductors are installed, without maintaining spacing between the cables,
through the same opening in wood framing that is to be fire- or
draft-stopped using thermal insulation, caulk, or sealing foam, the
allowable ampacity of each conductor shall be adjusted in accordance with
Table 310.15(B)(2)(a) and the provisions of 310.15(A)(2), Exception, shall
not apply.
- - - Where more than two NM cables containing two or more current-carrying
conductors are installed in contact with thermal insulation without
maintaining spacing between cables, the allowable ampacity of each conductor
shall be adjusted in accordance with Table 310.15(B)(2)(a).

Table 310.15.(B)(2)(a) is the derating table.

Thus, first there is the derating for ambient - which ALWAYS applies and
ALWAYS applies first (in severe cold climates, derating still "applies", it
is just that there is no derating "to apply"), then the derating for
bundling or lack of maintaining spacing applies, AND, if there is no
bundling or lack of maintaining spacing - which is what triggers Table
310.15(B)(2)(a) in 334.80 Ampacity - then there is no harm and no foul.

This tells me that they ran tests and determined that, as long as the cables
are spaced out, they are suitable for the same ampacity in thermal
insulation. That is because the NM-B uses 90 degree C rated insulation,
which apparently can withstand the accumulated heat of normal allowable
current flow within the conductor. The normal allowable current flow in a
#12 is 20 amps overcurrent protection, with normal less than 80% on the
circuit if a continuous load, if not a continuous then there will not be the
same heat build-up to be concerned with.
__________________
==========

HTH,

Twayne`

What HTH? The plagiarism? At least have the courtesy of linking to
information you cut and paste.
http://www.inspectionnews.net/home_i...nsulation.html
See? It's not so difficult.

Oh, and while you're pilfering stuff to make your point, don't be a
dweeb and leave out the part that directly contradicts what you're
trying to say - and from the same expert source! There's a word for
that and it's called lying. You omitted this part:

" Wiring in spray foam insulation
Quote:
Originally Posted by bob smit
Jerry, thanks for reminding me about that new addition to art 334.80
(2005) however, u failed to include "where bundled togeather" when
passing thru framing members to be insulated.
Bob,
I didn't forget that as you are referring to the paragraph above the
one I highlighted. See below in red for what you are referring to.
Quote:
If the cables are not bundled togeather between the studs then this
derating requirement would not apply."

Kinda changes things, doesn't it?

R