Romex in crawl space.

[AffableCurmudgeon]

I have a house with an attached garage. It is fed by a 15 amp circuit. I would like to add a 40 amp panel in the garage. I would feed a 240 outlet and a few 120 outlets from the new garage panel.

The current setup is this:

1. The 200 amp service disconnect is in a panel outside the house. The breaker is the only thing in that panel.

2. That outside panel feeds a second panel in the laundry room. That panel does not have master breaker. It only has individual breakers that feed the first floor living areas, garage and outside outlets and lights. The laundry room panel also has a 40 amp dual breaker that feeds a third panel on the second floor.

3. The second floor panel has breakers that feed upstairs living areas.

The garage wall where I would like to put the new 40 amp panel is less than 15 feet away from the first floor laundry room panel if I go down the wall from the panel and through the crawl space.

With all that, I have some questions:

1. Can I use 8-3 Romex to go from the laundry room panel to the garage through the crawl space?
2. Would I need PVC conduit in the wall and in the crawl space?
3. I would like to have a 40 amp disconnect in the new garage panel. Would I need a 40 amp breaker in the laundry room panel that would feed the garage panel as well?
4. What would be a better approach?

Thanks.

 

[Shiftless]

How many circuit breakers will you have in the garage panel?

 

[AffableCurmudgeon]

0ne 20 amp 120v breaker and one 30 amp 240.

 

[mike93lx]

If the underside of your floor joists are so wet that romex has problems, I would say you have much bigger ones.

Not sure what code says but I can say that my crawl, and many, many others, have lots of romex in them. I even added some recently.

 

[Shiftless]

Let’s wait for a pro electrician to chime in, but from what I know, if you have no more than 6 breakers in that sub panel, you don’t need a disconnect. Put the 40 amp breaker in the feeding panel.

 

[sparky 1971]

I have a house with an attached garage. It is fed by a 15 amp circuit. I would like to add a 40 amp panel in the garage. I would feed a 240 outlet and a few 120 outlets from the new garage panel.

The current setup is this:

1. The 200 amp service disconnect is in a panel outside the house. The breaker is the only thing in that panel.

2. That outside panel feeds a second panel in the laundry room. That panel does not have master breaker. It only has individual breakers that feed the first floor living areas, garage and outside outlets and lights. The laundry room panel also has a 40 amp dual breaker that feeds a third panel on the second floor.

3. The second floor panel has breakers that feed upstairs living areas.

The garage wall where I would like to put the new 40 amp panel is less than 15 feet away from the first floor laundry room panel if I go down the wall from the panel and through the crawl space.

With all that, I have some questions:

1. Can I use 8-3 Romex to go from the laundry room panel to the garage through the crawl space?
2. Would I need PVC conduit in the wall and in the crawl space?
3. I would like to have a 40 amp disconnect in the new garage panel. Would I need a 40 amp breaker in the laundry room panel that would feed the garage panel as well?
4. What would be a better approach?

Thanks.

Article 334 of the NEC covers NM cable, 334.15 is specifically about exposed work. You can use the 8/3 in the crawl space without conduit.

334.15 Exposed Work
In exposed work, except as provided in 300.11(B)), cable shall be installed as specified in 334.15(A) through (C).
(A) To Follow Surface
cable shall closely follow the surface of the building finish or of running boards.
(B) Protection From Physical Damage
cable shall be protected from physical damage where necessary by rigid metal conduit, intermediate metal conduit, electrical metallic tubing, Schedule 80 PVC conduit, Type RTRC marked with the suffix -XW, or other approved means. Where passing through a floor, the cable shall be enclosed in rigid metal conduit, intermediate metal conduit, electrical metallic tubing, Schedule 80 PVC conduit, Type RTRC marked with the suffix -XW, or other approved means extending at least 150 mm (6 in.) above the floor.
Type NMC cable installed in shallow chases or grooves in masonry, concrete, or adobe shall be protected in accordance with the requirements in 300.4(F) and covered with plaster, adobe, or similar finish.
(C) In Unfinished Basements and Crawl Spaces
Where cable is run at angles with joists in unfinished basements and crawl spaces, it shall be permissible to secure cables not smaller than two 6 AWG or three 8 AWG conductors directly to the lower edges of the joists. Smaller cables shall be run either through bored holes in joists or on running boards. Nonmetallic sheathed cable installed on the wall of an unfinished basement shall be permitted to be installed in a listed conduit or tubing or shall be protected in accordance with 300.4 Conduit or tubing shall be provided with a suitable insulating bushing or adapter at the point the cable enters the raceway. The sheath of the nonmetallic sheathed cable shall extend through the conduit or tubing and into the outlet or device box not less than 6 mm (1/4 in.). The cable shall be secured within 300 mm (12 in.) of the point where the cable enters the conduit or tubing. Metal conduit, tubing, and metal outlet boxes shall be connected to an equipment grounding conductor complying with the provisions of 250.86 and 250.148


You will have to use a 40 amp breaker in the laundry panel, you don't have to use a disconnect in the new garage panel since it's attached, but if you want to, get a 100 amp main breaker panel. If you go the 40 amp route there, you will have to get a hold down kit as well as a barrier. I just made a 316 mile round trip to pick one up because I did a poor job of planning.

Let’s wait for a pro electrician to chime in, but from what I know, if you have no more than 6 breakers in that sub panel, you don’t need a disconnect. Put the 40 amp breaker in the feeding panel.

If it's in the same structure, that doesn't apply.

 

[AffableCurmudgeon]

@sparky 1971 , thank you.

 

[yatg]

If you think you're going to add more circuits in the garage in the future, then upgrade to 6/3 copper NM.
$159 gets you a 25ft roll at Home Depot.

If you really want to upgrade, use 2-2-2-4 AL SER.
$60 gets you 25ft at Lowes (2.40/ft)

 

[AffableCurmudgeon]

If you think you're going to add more circuits in the garage in the future, then upgrade to 6/3 copper NM.
$159 gets you a 25ft roll at Home Depot.

If you really want to upgrade, use 2-2-2-4 AL SER.
$60 gets you 25ft at Lowes (2.40/ft)

Thank you.
I think based upon what you and @sparky 1971 said, I would use a 100 amp load center in the garage and feed it using a 60 amp breaker with 2-2-2-2-4 AL SER cable From the laundry room. Thanks again.

 

[pattenp]

FYI the 2-2-2-4 Al SER can handle up to a 90A breaker if you find you need more power to the garage in the future.