Today, I helped my neighbor, who is a plumber, install radiant heating in the slab of a new-construction building. If you aren’t familiar, it looks about like this. So, all that 1/2" pex has to be tied to the rebar every two feet. This particular building was about 75’x100’. It took two of us doing nothing but bending over and zip-tying 7 hours to do just that part of the job. This is not a fun job. And we were not slacking, at all. It was many thousands of zip ties.
What that photo doesn’t show is that all the ends of those blue zip ties have to be cut off, and cannot be left laying on the insulation, because they’ll float up when the concrete is poured, screwing up the finish work of the slab.
Is there a tool that would accomplish this faster? It would not necessarily have to be zip ties, but it can’t really be sharp metal bands, because that could potentially cut through the Pex as the concrete work gets done.
I’m sure you can find something easier to attach than a zip tie that won’t need a piece clipped off. I’d be surprised if there isn’t something already made just for this purpose. There are certainly zip ties in different sizes that wouldn’t need to be trimmed.
Ha, you guys are fucking awesome. His wife (my ziptie partner) was just saying she would pay $2000 for a tool that would do this, and here it is, for $14. Love you!
Wait. The cable tie gun is cool and all, but it doesn’t actually wrap the cable around the stuff to be tied, right? I mean, it’s still better than nothing, but not exactly what we’re looking for. We were hoping for a more all-in-one solution.
Clips are difficult because they’re much more expensive than zip ties, and tend to be one size fits all, which is a problem with rebar, which frequently overlaps.
You should look at Pex suppliers. Those guys have a clip gunyou could use to clip the tube to the insulation. There’s a pneumatic model that should let you get that floor done in a couple of man-hours.
Tie around the cable, stick end through lock, use the gun to tighten and cut.
Goes faster than it sounds. 10 seconds or faster each after you’ve done a few.
No, they don’t. Cable tie guns are used for making cable ties really, really tight. In fact, many of us in the food industry will use them to tie zip ties around bags tight enough that liquid won’t leak out of them, even when you a gallon bag full of liquid into a pot of boiling water.
I can’t imagine anything that could wrap it around your work, thread it through the end/lock thing and then tighten it. Not without it being custom made for the specific application. But still, on a large project it’ll stop you arm from wearing out and you from ending up with blisters and wondering if there’s a better way to do it.
OTOH, I imagine you don’t need these ties to be to tight, they just need to be kept in place. I’ve never played with pex, but this might break it.
I do know of a metal tie system, but they still need to be threaded by hand and I’d be concerned about them rusting over time.
The clips mentioned up thread would probably be the way to go for any project larger then a small bathroom. They also have the advantage of keeping everything perfectly even so you can set your tile or concrete right over them.
I’ll take his/your word for it, but I’m surprised those zip tie ends would float. My first thought was to just ignore them.
Or not, actually. In most industries having cable ties too tight is a much bigger problem than too loose. There are a whole range of high end cable tie guns that have a controlled tension setting at cut off.
I have an adjustable zip tie gun that goes from just barely tight to Holy Shit!
What I have found doing wiring looms is it is fastest to install a section of zip ties then grab the gun and clip them all at once.
Why couldn’t you use duct tape? (Or some similar type of tape.)
Seems like about 4" (or so) strips could fit around the pex & rebar without needing tying, and hold it fine until the concrete is poured. And I have seen devices where you set the measured length needed, then each time you pull the handle, it unrolls that length of tape and cuts it off. Commonly used in shipping departments.
I’d think that this would be much faster than zip ties.
I wondered about that. It’s possible that there’s a warranty issue if unapproved materials are used on the tubing. I don’t know how these things get guaranteed, but it’s got to be a nightmare to install that stuff, pour a slab, and then find out water won’t flow through the tubing.
Sure, but what do you do if there’s a failure after the concrete is poured? Really, I can’t see how duct tape could do anything to PEX, it’s polyethylene, nearly immune to all solvents. I can’t see the tails of the cable ties being a problem either, and you can get ties in different lengths that wouldn’t leave enough of a tail to possibly make a difference.
I think the real problem with duct tape (which I’m not actually convinced would be faster–it takes about 5 seconds to do each zip tie, which isn’t a long time, it’s just so damn many of them) is that while they’re pouring the slab, the concrete guys are wading around in the wet concrete, stepping on stuff. I don’t know that duct tape would hold if some guy stood on it wrong.
The tails of the zip ties end up mixed up in the concrete, and interfere with the big fan machine they use to slick it down. It’s not a theoretical problem, it happened the first time my neighbor installed one of these systems (in his own house, I believe.) The ends of the ties have to be removed.
Those mats are neat, but they seem designed for applications where the floor is already in place. I don’t know what you’d attach them to when you’re starting with dirt and a rebar grid.
Clips might be an option, but again you have the situation of the guys wading around in the wet cement. They’d have to be strong and secure. I don’t really see any that would fit the bill.
How much cement is poured above the pex? Because if it is more than an inch or so, just buy shorter zip ties and don’t clip them. You can get them as short as 4 inches long, which wouldn’t even wrap around the rebar.
