334.40

Status
Not open for further replies.
jap said:
That, and, If it's done right, a lazer is set up, and, the strapping is shimmed to make the ceiling straight even if the floorjoists aren't.

Not sure of their real reason.
Click to expand...

That is the "real" reason - shimming for best leveling.
 
LarryFine said:
The OP said they're 1x3s, which are 3/4" thick. A cable perpendicular to the joists would be in that 3/4" space, so the surface of the cable would be less than 3/4" from the back of the drywall.
Click to expand...

The cable can touch the back of the drywall as long as it's 1.25" from the piece of wood that will hold the drywall up.
 
Run the nm cable between the strapping and staple to the beams. Not an issue for 2x4 or 1x4. Not sure how the op has 1x3 if there is 1.25 inches clear
 
kwired said:
Aren't those engineered joists like shown pretty straight to begin with?

I have seen strapping and shimming when needed to level a surface, never on engineered joists though.
Click to expand...

It can also be used to limit sound transmission. The connection point to the joists above is limited to the small point where the furring and the joists meet not the entire floor joist transmitting sound. In commercial work we typically see these to do the same thing.

ProSTUD-RC.jpg
 
Often strapping is used if the ceiling joists are 24" OC and then the strapping is set at 16" OC, so 1/2" GWB can be used. with 2x joists, the strapping is wider and easier to fasten to.
 
tom baker said:
Often strapping is used if the ceiling joists are 24" OC and then the strapping is set at 16" OC, so 1/2" GWB can be used. with 2x joists, the strapping is wider and easier to fasten to.
Click to expand...

The floor joists in the picture look to be on 16" centers already.

JAP>
 
LarryFine said:
I thought that referred to depth from the joist face, not distance to the side from it.
Click to expand...

It's either. If you had furring strips on block or 1 5/8" studs you could use something like a Colorado Jim to keep the cable 1.25" away from the edge of the strip.

206ecmCQfig1.jpg
 
jumper said:
Both.

Think of furring out a basement wall. Run cable between furring strips and stay away from strips 1.25”.
Click to expand...
but you are running parallel to those wall strips. I guess one could run lines parallel to the OP's ceiling strips in similar fashion, but I think what was described was running perpendicular to the strips (parallel to the ceiling joist) and just leaving them lay freely on the furring strips. I think in that situation they need to be higher off the strips to be out of the 1-1/4 zone, regardless they still need to be secured anyway.
 
I wonder if when it was roughed in, the cables weren't even run to the panel yet. Rough inspection passed because "we'll staple all those up for finish". Then before finish they go ahead and rough the basement, finish the whole thing, inspector comes back out for the final and all the receptacles work, are properly grounded, lights work, etc so he passes the final without ever looking at the rough wiring for the basement finish. Possibly because he didn't recall that the basement hadn't been roughed in when he was out there last.
 
jaylectricity said:
I wonder if when it was roughed in, the cables weren't even run to the panel yet. Rough inspection passed because "we'll staple all those up for finish". Then before finish they go ahead and rough the basement, finish the whole thing, inspector comes back out for the final and all the receptacles work, are properly grounded, lights work, etc so he passes the final without ever looking at the rough wiring for the basement finish. Possibly because he didn't recall that the basement hadn't been roughed in when he was out there last.
Click to expand...

Totally possible.

Another one is that the cables were fished in later. Any chance there a remodel before you got there? I know the house was newish, but wierd stuff happens, just like your scenario.
 
Hold on guys...I'll straighten out this 1.25 inch issue for you.

Massachusetts revised 334.17 so the 1.25 inch rule only applies to bored holes. So running romex across the top of them strappings is OK...and really fast to ruff a home. I never had any problem with screws hitting the romex.

Here is the amendment...

334.17 Through or Parallel to Framing Members and Furring Strips. Types NM, NMC, or NMS cable shall comply with 300.4 where installed through studs, joists, rafters, and similar members. Grommets or bushings shall be used in metal studs as required in 300.4(B)(1),shall remain in place during the wall finishing process, shall cover the complete opening,and shall be listed for the purpose of cable protection.In both exposed and concealed locations, where the cable is installed parallel to framing members, such as joists, rafters, or studs, or is installed parallel to furring strips, the cable shall be secured so that the nearest outside surface of the cable is not less than 19 mm (¾ in.) from the nearest edge of the framing member or furring strip where nails or screws are likely to penetrate. Where this distance cannot be maintained, the cable shall be protected from penetration by nails or screws by a steel plate, sleeve, or equivalent at least 1.6 mm (1/16 in.)thick. A listed and marked steel plate less than 1.6 mm (1/16 in.) thick that provides equal or better protection against nail or screw penetration shall be permitted for this purpose.Exception: For concealed work in finished buildings, or finished panels for prefabricated buildings where such supporting is impracticable, it shall be permitted to fish the cable between access points.
 
Status
Not open for further replies.
Top