is it worth insulating riser inside the wall of the main house?

verbal329

As stated - I have the floor to my full bathroom open right now, but plane to close it up again in the next day or two. While it's open, is it worth slipping some 1/2" fiberglass pipe insulation over the riser that drops down one storey in to the basement?



Ultimately, I guess the question is, once the risers are inside the house proper, as opposed to the basement, should they be insulated if I have the momentary opportunity to do so?

ChrisJ

Inside

If its inside the wall I don't see why you can't just use some standard fiberglass bats. Just insulate the wall like normal, filled but nice and loose. If you have access to it I would definitely insulate it especially if its in an outside wall.



Also is a good time to make some shims out of a plastic milk carton to keep the pipe from rubbing against any wood if you've had popping noises in the past. Make sure you staple it in place otherwise it will work its way out. If you bend a piece and get it around the pipe and bend a lip over that can be stapled down. This keeps the pipe from rubbing against the staple.



I've attached a horrible childish drawing I just tried to make of how the shim is made to wrap around the pipe.

verbal329

interior wall

It's an interior wall, running immediately adjacent to the chimney in the middle of the home. Clearance and access is minimal around the pipe as it heads down, so since it's worth doing, I'll likely use pipe-style insulation anyway, as they should slip on and slide down, with some pushing...I think batts would just get hung up and caught on the plaster keys on the way down. I think I have room for 1/2" thickness, probably not 1".



...and thanks for the shim idea, I'll do that since I have it open. There's definitely one spot where it rubs.

MDNLansing

Let It Run

Make sure you let it run for a day or two before you button up the floor. Insulating is always a good idea, but it does change the steam and condensate characteristics. Some people have insulated pipes and then heard water hammer. Just make sure the insulation isn't causing any hammer issues before you close it up. You should know after a couple of cycles if you're going to have issues or not.

verbal329

funny...

...in another, much longer previous post I described how insulating the header and mains in my basement made the whole system in my house start making a truckload of noise - though I was also running with a significant setback, which I've now learned helps cause that.

RJ_4

shims

Very interesting, can you post a picture of this, maybe around a piece of scrap pipe11

ChrisJ

Shims

Hi RJ,



I can try, I just don't know if we have a milk jug laying around. You cut a piece that will wrap around the pipe and isolate it from wood to allow it to move smoothly without popping. I added the tongue onto it so it can be stapled to keep it from working its way out.