Best method to support horizontal steam piping

JimmyNJ

This is probably a ridiculous question for many on this site....but I was wondering what the best method is to support horizontal runs of steam piping. Is it just metal chain that are nailed/screwed into the floor joists (which is how I see my Mains in the basement currently being supported). Reason for my questions is that I had a new radiator put into new family room added on -and my plumber who ran the new takeoff to the new family room radiator did not use any means to support the new piping (which I would estimate is is about 20 feet in length) other than the couple of holes he had to drill in the family room floor joists to run the piping through (and he did not leave enough "room" to accommodate for pipe expansion when he drilled those holes so as a result, I get "knocking" in the family room floor when the system is heating up). My plan is to try to make the openings where the pipe is currently going through the floor joists bigger so I don't have pipe on wood - but I will then need to suspend the pipe in the air so that it just doesn't rest on the bottom of the floor joist hole and I ruin the current pitch which is good (I never get any water hammer in this pipe - just the banging against the floor joists. Should I just put some chain around the pipe in a couple of places and fasten them to the floor joists or is there some other pipe support I should consider? Sorry for writing a novel about something so trivial.

JStar

You can use perforated metal strap. It's easy to use and holds up pretty well.

JimmyNJ

Thanks Joe - Do you do work in my neck of the woods in NJ? (Morristown area) Have been thinking about the possibility of using my boiler to create a new hot water zone but quite frankly would need an expert that understands both steam and hot water to come in and look at the existing set-up and let me know what my options are.
-Jimmy

pecmsg

I heard
Take a tupperware dish and cut out a flat section. Slip it between the wood and pipe and secure it. The pipe will slide on the plastic no noise.

KC_Jones

pecmsg said:

I heard
Take a tupperware dish and cut out a flat section. Slip it between the wood and pipe and secure it. The pipe will slide on the plastic no noise.

Instead of wasting a tupperware dish use an old milk jug...it works great!

Fred

Does the noise sound like expansion noises or actual knocking/banging? If Expansion (sounds like the pipe rubs against the wood joists) then you can open the holes a bit or try the milk carton/tupperware trick and fix the problem.
If actual knocking/banging, that may indicate there isn't enough pitch in the pipe or radiator to let the water return back to the boiler and steam hit that water causing the noise. It is unusual to run a steam pipe through a joist as opposed to running it under the joists so that pitch can be adjusted. As that joist settles, the pipe will also and create a sag that will let water pool.
Is this a 1 pipe or 2 pipe system? What size (diameter) is the pipe in question? Can you post a picture?

KC_Jones

In addition to what Fred said, is this a steel pipe or did they run copper?

JimmyNJ

Hi all: Thanks for the many tips (I still think I would need to make the hole a bit larger as I don't think there is enough room to even slide a piece of thin plastic around the pipe. Once I get home tonight I will take a couple of pics and post them. The sound is definitely more like a couple of big "knocks" on the floor joists. The system is a 1 pipe steam system and the piping is black steel (1" pipe I believe).

JimmyNJ

here are some pics. I know that two elbows are probably what many may think are responsible for the knocking but I honestly don't think they are. <img src="https://us.v-cdn.net/5021738/uploads/FileUpload/ec/9528edfda4665b8e26bbc9256bb908.jpg" /><img src="https://us.v-cdn.net/5021738/uploads/FileUpload/c9/7a5e7a63ef4bda4ca37ac085303686.jpg" /><img src="https://us.v-cdn.net/5021738/uploads/FileUpload/c9/7a5e7a63ef4bda4ca37ac085303686.jpg" /><img src="https://us.v-cdn.net/5021738/uploads/FileUpload/a1/a6f3ec7522d039b9f66295068a21b3.jpg" /><img src="https://us.v-cdn.net/5021738/uploads/FileUpload/58/138002331f2c1c7092b873a9616ad6.jpg" />

Fred

I don't see anything there that would cause a problem. Maybe it is just rubbing from expansion.

JimmyNJ

That's what I believe it is as well. I will try the milk cartoon trick - hopefully the plastic won't melt!

Fred

Oddly enough, it doesn't

hboogz

I'm actually going through something similar on a riser between the 1st and 2nd Floor. After laying the new subfloor, I think the carpenter I was working with got too aggressive with adding blocking so that we can get really tight around the riser. Incidentally it causes about 5 knocks when steam kicks in. Since there are two elbows connecting via close nipple that connect that riser to the takeoff from the main, It appears during expansion something is rubbing. I feel the plywood actually vibrate. lol. No knocking whatsoever when we were down to the joists for weeks. Once plywood went down, knocking.

Fred

There is a reason they make those escutcheon rings to trim out around the pipe. Need to leave room for expansion.

JimmyNJ

Update: I cut sections from a milk container and inserted them under the pipe in the sections where it rested on plywood - knock on wood (no pun intended) but it seems to have worked! Thanks a bunch for the tip!

KC_Jones

Every once in a while there actually is a simple fix.