DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (http://www.diychatroom.com/)
-   Electrical (http://www.diychatroom.com/f18/)
-   -   Routing coax through small section of cold air return (http://www.diychatroom.com/f18/routing-coax-through-small-section-cold-air-return-166726/)

gta 12-17-2012 06:02 PM

Routing coax through small section of cold air return
 
Okay. I'll try to explain this as clear as possible.

My cold air return is basically a joist cavity for half the run and then the other half is duct work tied in to the joist cavity. The cold air return vent is on the first floor and that ties into the joist cavity in the basement.


I would like to know if its possible to make a small hole in one of the joist to run coax cable up about 18 inches to the first floor?


I read somewhere that as long as the cable is not running along the entire length of the return it is okay. It must also be perpendicular and plenum rated.

Any truth to this?

TTW 12-17-2012 06:09 PM

Quote:

Originally Posted by gta (Post 1074779)

I read somewhere that as long as the cable is not running along the entire length of the return it is okay. It must also be perpendicular and plenum rated.

Any truth to this?


It must be perpendicular and plenum rated


Correct.

gta 12-17-2012 06:25 PM

Is this commonly done in residential houses?

brric 12-17-2012 07:12 PM

Quote:

Originally Posted by TTW (Post 1074786)
It must be perpendicular and plenum rated

Correct.

It is not a plenum. NM-B is run perpendicular all the time and it is not plenum rated.

gta 12-17-2012 07:16 PM

So you can run perpendicular if its a joist cavity and not metal ductwork right?


Also, what would be considered a plenum in a residential house?

NJMarine 12-17-2012 07:26 PM

It can be run perpendicular to the plenum without it being plenum rated. If you run the length of the plenun than it has to be plenum rated.

brric 12-17-2012 07:29 PM

Quote:

Originally Posted by gta (Post 1074832)
So you can run perpendicular if its a joist cavity and not metal ductwork right?


Also, what would be considered a plenum in a residential house?

The top of the furnace where the duct work branches from is the plenum.

TTW 12-17-2012 07:40 PM

:oops:I just noticed you are talking about COAX!

Do what you want and have fun!


Thanks for the clarification on the plenum rating guys!:thumbsup:

gta 12-18-2012 01:14 AM

So what brric said about NM-B wire can also apply to coax right?

I just want to be absolutely sure.

Thanks.

sublime2 12-18-2012 02:09 AM

Quote:

Originally Posted by gta (Post 1075067)
So what brric said about NM-B wire can also apply to coax right?

I just want to be absolutely sure.

Thanks.

Yes,no concerns with coax/ video cable.

k_buz 12-18-2012 06:54 AM

There ARE codes in the NEC for CATV installation. It is not a "free-for-all" as some seem to think.

TTW 12-18-2012 07:36 AM

820.113 Installation of Coaxial Cables. Installation of co-
axial cables shall comply with 820.113(A) through (K).
Installation of raceways shall comply with 820.110.

(A) Listing. Coaxial cables installed in buildings shall be
listed.
Exception: Coaxial cables that comply with 820.48 shall not
be required to be listed.
(B) Fabricated Ducts Used for Environmental Air. The
following cables shall be permitted in ducts as described in
300.22(B) if they are directly associated with the air distri-
bution system:
(1) Up to 1.22 m (4 ft) of Type CATVP cable (the P means plenum listed)

(C) Other Spaces Used For Environmental Air (Plenums).
The following cables shall be permitted in other spaces used
for environmental air as described in 300.22(C):
(1) Type CATVP cable
(2) Type CATVP cable installed in plenum communica-
tions raceway
(3) Type CATVP cable supported by open metallic cable
trays or cable tray systems
(4) Types CATVP, CATVR, CATV, and CATVX cables in-
stalled in raceways that are installed in compliance
with 300.22(C)

300.22 Wiring in Ducts Not Used for Air Handling,
Fabricated Ducts for Environmental Air, and Other
Spaces for Environmental Air (Plenums).

C) Other Spaces Used for Environmental Air (Ple-
nums). This section shall apply to spaces not specifically
fabricated for environmental air-handling purposes but used
for air-handling purposes as a plenum. This section shall
not apply to habitable rooms or areas of buildings, the
prime purpose of which is not air handling.


Exception: This section shall not apply to the joist or stud
spaces of dwelling units where the wiring passes through
such spaces perpendicular to the long dimension of such
spaces.



The way I am reading this, the perpendicular exception also applies to CATV cable.

Thanks for the homework!

I am taking the NEC class next semester, and am trying to get a head start.

TTW 12-18-2012 07:55 AM

Just found this, it sure helps!


http://i1294.photobucket.com/albums/...psfbcc9533.png

sublime2 12-18-2012 10:53 AM

Quote:

Originally Posted by TTW (Post 1075117)
820.113 Installation of Coaxial Cables. Installation of co-
axial cables shall comply with 820.113(A) through (K).
Installation of raceways shall comply with 820.110.

(A) Listing. Coaxial cables installed in buildings shall be
listed.
Exception: Coaxial cables that comply with 820.48 shall not
be required to be listed.
(B) Fabricated Ducts Used for Environmental Air. The
following cables shall be permitted in ducts as described in
300.22(B) if they are directly associated with the air distri-
bution system:
(1) Up to 1.22 m (4 ft) of Type CATVP cable (the P means plenum listed)

(C) Other Spaces Used For Environmental Air (Plenums).
The following cables shall be permitted in other spaces used
for environmental air as described in 300.22(C):
(1) Type CATVP cable
(2) Type CATVP cable installed in plenum communica-
tions raceway
(3) Type CATVP cable supported by open metallic cable
trays or cable tray systems
(4) Types CATVP, CATVR, CATV, and CATVX cables in-
stalled in raceways that are installed in compliance
with 300.22(C)

300.22 Wiring in Ducts Not Used for Air Handling,
Fabricated Ducts for Environmental Air, and Other
Spaces for Environmental Air (Plenums).

C) Other Spaces Used for Environmental Air (Ple-
nums). This section shall apply to spaces not specifically
fabricated for environmental air-handling purposes but used
for air-handling purposes as a plenum. This section shall
not apply to habitable rooms or areas of buildings, the
prime purpose of which is not air handling.

Exception: This section shall not apply to the joist or stud
spaces of dwelling units where the wiring passes through
such spaces perpendicular to the long dimension of such
spaces.

The way I am reading this, the perpendicular exception also applies to CATV cable.

So it seems it is a "free for all" in this situation.
How about that!

Jim Port 12-18-2012 11:00 AM

It is not a free for all. The cable needs to follow the rules shown above.

Sublime, many here try to only give answers that follow the code. When you give answers it would help greatly if you would give correct answers also not just ones you agree with.


All times are GMT -5. The time now is 08:48 AM.