Raceway for NM/Romex through sheetrock/drywall panel?

[pauls_workshop]

Hi all, I'm working on a basement workshop project doing it all myself. I have most of it figured out and getting close to the rough inspection. What I'm doing is dividing my basement in half with a new wall under a beam in the middle of the space and another wall dividing that section to form a woodshop space and a utility room. I'm not using any ceiling but just painting the joists white for a woodshop with some low hanging ducts in the space, making a real ceiling less than ideal but ok for shop type use for the space.

For the area above the beam and between open joists above it between the two halves of the basement, I'm just placing a little square of drywall (single sheet) and not a proper wall to have some noise control and also avoid the shop dust from getting into the other half of the basement. So it is a little "mini wall" to close off the joist openings above the beam/wall in the space a ceiling would normally have covered over. Passing through these single drywall squares are a few Romex/NM electrical wires, perpendicular through the drywall squares above the beam.

My question is what is the right thing to do for that? Can I just drill or cut little cutout notches through those squares of drwall between joists and have the NM wire go through that, then come back later and "fill in" around the Romex with drywall mud, sand close to it, then paint? So the NM would come straight out and through the drywall? Is this ok with code? Or is some kind of raceway better, like a short length tube maybe of PVC or EMT around the NM, just long enough to pass through the drywall sheet (maybe 1" or 2" long) and mud up to and around this raceway instead? But these wires are all in place now, so would have to maybe cut any raceway with a slit or small axial cutout, wrap around the wire or get the wire into this cutout area, then insert. What is best way to handle this and to code? Thx all - Paul

 

[pauls_workshop]

Jeremy, many thanks for your thoughts on this. I wasn't thinking about caulk for some reason. I suppose that could work. Also, didn't know the rule on 2 wires! That is a good one. Anyone else have any other thoughts on this one?

 

[Tim The Tool Man]

If it were me I would just make sure the romex was tacked flush against the floor joist on one side of the opening and then C-notch the edge of the sheetrock panel you are installing instead of drilling a round hole through it. Since this is not an official fire wall, etc. the only code issue that I would think you might run into is related to the number of romex wires you can have in a single structural penetration of which you can not have any more than 2 per hole. If you have more than 2 romex cables to run just notch a second hole an inch or two above the first one and then run the extra cable in that hole and you should be fine.

The intent of that code is to prevent a spot of heat build-up from having too many wires packed tightly in one spot, or from having a short or nail penetration in the future from affecting and possibly damaging a bunch of cables all at once.

I would probably also use a paintable latex caulking around the wires instead of drywall mud. If those wires ever get bumped or tugged even a little bit in the future the drywall mud will just crack, break, fall off and leave you with a hole and some missing paint whereas the caulking could take a little jostling and still be fine.

I agree with this and would only add that in my neck of the woods the inspector would fail me if I use anything other than that expensive orange spray foam in each and every intrusion even though it is just a partition wall. I would also have to add a minimum of 12" deep layer of Roxul behind those sheetrock baffles.

 

[pauls_workshop]

hmmmm. I guess I could use a fireblock type foam instead of the caulk. Don't really want to do any insulation behind the panels though unless I had to. I did buy some of the red fireblock caulk from Menards (the $5 stuff, not the $11 stuff that is better), just to fill the vertical holes in the walls for the wiring and even put in horizontal "fireblock" cut studs in each section of each wall in the middle to add some fireblocking. While not "fireproof" walls, I thought that a good idea in general to do those things, esp since one wall is then a furnace/utility closet wall, but I left about a yard clearance at the furnace itself to the new wall.

I suppose that foam could be used too, but not sure how that would like paint. I do also have a number of other cutouts in the "real" walls for pipes, ducts, and some other wires to pass though. I'll use a thimble for the gas water heater exhaust pipe that runs through the wall, but for the other things that aren't hot, Is the expanding foam the best choice there to mate right between the drywall edge and the duct/tube/wires passing through?

If so, how best would you smooth that flat with the plane of the drywall before painting to try to blend it in as much as possible? Sander? Multi-tool ******** with a cutter tool or scraper tool (other tool?). Have to be sure not to hurt the thing passing through the wall but would like these to "blend in" to the drywall plane as best as possible to be less noticeable! It is my little 1 car dream shop space after all here we are talking about! I'm even doing an epoxy floor for it in the flooring section ! - Paul

 

[madosta]

i still have to reglaze the windows above it

oh really spammer!?

 

[Tim The Tool Man]

hmmmm. I guess I could use a fireblock type foam instead of the caulk. Don't really want to do any insulation behind the panels though unless I had to. I did buy some of the red fireblock caulk from Menards (the $5 stuff, not the $11 stuff that is better), just to fill the vertical holes in the walls for the wiring and even put in horizontal "fireblock" cut studs in each section of each wall in the middle to add some fireblocking. While not "fireproof" walls, I thought that a good idea in general to do those things, esp since one wall is then a furnace/utility closet wall, but I left about a yard clearance at the furnace itself to the new wall.

I suppose that foam could be used too, but not sure how that would like paint. I do also have a number of other cutouts in the "real" walls for pipes, ducts, and some other wires to pass though. I'll use a thimble for the gas water heater exhaust pipe that runs through the wall, but for the other things that aren't hot, Is the expanding foam the best choice there to mate right between the drywall edge and the duct/tube/wires passing through?

If so, how best would you smooth that flat with the plane of the drywall before painting to try to blend it in as much as possible? Sander? Multi-tool ******** with a cutter tool or scraper tool (other tool?). Have to be sure not to hurt the thing passing through the wall but would like these to "blend in" to the drywall plane as best as possible to be less noticeable! It is my little 1 car dream shop space after all here we are talking about! I'm even doing an epoxy floor for it in the flooring section ! - Paul

If the voids are relatively tight, fire caulk would be fine I would think...

and if you do paint any of it, wait until the inspector is done and gone...

 

[pauls_workshop]

Thanks guys! Lots of good discussion and pros/cons here. Well, for the drywall panels, my cutouts will be small for the NM so caulk could be used there easily. But on the other wall with the other pipes/ducts/etc coming through it, I really can't use caulk there. I might have a 1" gap in a few spots from the "wall framing" around these openings to the pipe/wire/duct etc where I just couldn't frame it tight. So for that, I really could make use of the foam best there. I saw a youtube video of a guy lighting fire to the various foams though - all of the cheap ones did catch on fire readily still including the great stuff one above. They are just "not as bad" as the non-fireblock type spray foams, which are insanely flammable I understand. Frankly, after seeing that video, I can't believe the standard spray foams are even on the market at all for any use. Does anyone have a good highly fire resistance spray foam they would recommend to use, much better than the great stuff or similar? And if so, where could you buy it? thx all - Paul

 

[pauls_workshop]

Here is that YouTube link! Pretty eye opening. Where can you get the one that did well and what does it cost?

 

[pauls_workshop]

Jeremy, many thanks. You have been a great resource and I really appreciate your knowledge. I'm going to do what you have suggested and use caulk and foam where needed. But I really DO want to try to buy that better brand of spray foam shown in the youtube video and not the great stuff one that still burned fairly easily. If anyone out there can identify what that stuff is and where to buy it, please post here for me and others too ! thanks all - Paul

I can't help much with fire resistant foams, because I have never needed to use them before. Commercially around here it was always just fire caulk for fire barriers, and for larger gaps lots of rock wool smashed in to fill them up before skimming it all over lightly with fire caulk. For larger gaps that are not fire rated I have always just wedged a scrap piece of wood, plywood, sheetrock, insulation, etc. to fill as much of the gap as possible and then caulked that filler piece into place whenever it doesn't have to look too pretty. That saves a lot of caulk and it has always worked for me. It will still turn out looking pretty good with a little effort on your part. There are lots of little things you can do.

You could also use spray foam and after it is done drying use a very sharp knife to cut it as flush as possible with the plane of the wall. Then just put a thin layer of caulking (possibly just with your finger) over the top of the remaining foam and go ahead and paint the caulk too if you are going to paint the wall already. When you are done it will look almost exactly like painted brick grout if you do a good job and it will fill larger gaps pretty easily.

Even expanding foam will stick and fill in gaps much better if the gap is made smaller with some sort of a filler first. Many spray foams do not expand fast enough to easily fill a long gap of more than about 3/4" without just building up a little bit and then falling out onto the floor on you in one big sticky slimy noodle.

 

[pauls_workshop]

thanks! That is not too bad. About $24 + shipping for 24 ounces. Wish I didn't have to order it though. This is worth it for the fire protection it has vs. the others. - Paul