running wires - truss question

[jpcjguy]

Some questions on running wires across my trusses. The space in the pic is the "triangle" behind my attic truss room. It is about 2.5-3ft high. Regarding running my wires across, is this ok for inspection? Should I mount a 1x6 vertically, separating it from the rest of the area?
Also, can I install junction boxes on the slope also (blue box in pic)?

Getting started in wiring up the garage!

 

[Innovate1]

They may want a board run parallel to the wires to protect them from possible damage. That's the only issue I see.

 

[jpcjguy]

They may want a board run parallel to the wires to protect them from possible damage. That's the only issue I see.

That is why I mentioned a 1x8 or 1x8 board on end to make a small "triangle" that the wires are behind in that space.
Like the green "board" I added in the attached pic.

 

[ard]

So this space is “behind” a room that could be occupied? Like a crawl space where there will be no activity nor storage, only qualified construction and maintenance personnel if there ever were repairs or future construction activity?

If so, IMO it is fine as is, no need for a board. In fact the board would be a PITA in the future. I would absolutely NOT ‘box it in’.

Obviously the inspector has the final say.

 

[jpcjguy]

So this space is “behind” a room that could be occupied? Like a crawl space where there will be no activity nor storage, only qualified construction and maintenance personnel if there ever were repairs or future construction activity?

If so, IMO it is fine as is, no need for a board. In fact the board would be a PITA in the future. I would absolutely NOT ‘box it in’.

Obviously the inspector has the final say.

It is the space marked by the red triangles in the truss drawing attached.
Access will be minimal - only by me for repairs, more wiring, etc. as you stated.

 

[ddawg16]

It is the space marked by the red triangles in the truss drawing attached.
Access will be minimal - only by me for repairs, more wiring, etc. as you stated.

No board needed. Just staple the wires to the trusses....

And make sure you staple the romex within 8" of the box.

 

[checkthisout]

That is why I mentioned a 1x8 or 1x8 board on end to make a small "triangle" that the wires are behind in that space.
Like the green "board" I added in the attached pic.

Chapter 3 Wiring Methods and Materials
Article 334 Nonmetallic-Sheathed Cable: Types NM, NMC, and NMS
334.23 In Accessible Attics. The installation of cable in accessible attics or roof spaces shall also comply with 320.23.

Article 320 Armored Cable: Type AC
320.23 In Accessible Attics. Type AC cables in accessible attics or roof spaces shall be installed as specified in 320.23(A) and (B).

(A) Where Run Across the Top of Floor Joists. Where run across the top of floor joists, or within 2.1 m (7 ft) of floor or floor joists across the face of rafters or studding, in attics and roof spaces that are accessible, the cable shall be protected by substantial guard strips that are at least as high as the cable. Where this space is not accessible by permanent stairs or ladders, protection shall only be required within 1.8 m (6 ft) of the nearest edge of the scuttle hole or attic entrance.

(B) Cable Installed Parallel to Framing Members. Where the cable is installed parallel to the sides of rafters, studs, or floor joists, neither guard strips nor running boards shall be required, and the installation shall also comply with 300.4(D).


I think it boils down to deciding whether or not the area is considered accessible by permanent stairs or ladder.

Based on the fact that there is osb there for walking on, I would say it is but ultimately it's the inspector who will decide.

Don't be afraid to call or better yet, e-mail the inspector assigned to your job.

 

[jpcjguy]

I will reach out to the inspector and get his thoughts. Appreciate the input!

 

[pattenp]

IMO running boards are needed based on the NEC which has already been cited. Why not run the wire on the backside of the truss members?

 

[jpcjguy]

Emailed inspector picture with "green board" in it and said that was fine!

 

[alfredeneuman]

And make sure you staple the romex within 8" of the box.

334.30 Securing and Supporting. Nonmetallic-sheathed cable
shall be supported and secured by staples; cable ties listed and
identified for securement and support; or straps, hangers, or
similar fittings designed and installed so as not to damage the
cable, at intervals not exceeding 1.4 m (41∕2 ft) and within
300 mm (12 in.) of every cable entry into enclosures such as
outlet boxes, junction boxes, cabinets, or fittings. Flat cables
shall not be stapled on edge.

 

[checkthisout]

Emailed inspector picture with "green board" in it and said that was fine!

Easy peasy!

 

[matt_i]

Just make sure you can swing the hammer! Its easier if you can work from below on a ladder with the open trusses than have to crawl way out there on your belly on support planks. Every other truss if you frame 24" on center.

 

[ard]

Emailed inspector picture with "green board" in it and said that was fine!

lol

of course he did.

The question was not 'is the added board OK'.

The question should have been "Im running the wires out at the edge, not on the OSB, it isnt within 7 ft of a hatch and there is no permanent access. Will that be adequate?"



Id have proposed 2x4 nailed flat onto the edge of the OSB- protection, but easy to get at in the future.

 

[1MtnGoat]

Can run wires across outer ends of truss where "headroom" is three feet or less. No protection necessary. Where headroom is greater run wire along side a 2x4 or staple to side of bottom cord of truss. The reasoning is not not to be able to "walk" on the wires.