Frozen Pipe - Toilet Supply Line

Hi All,

We have a second floor toilet that always freezes when it gets below, say, 25 degrees F (I'm in NJ, so not a rare occurrence during the winter). Its the only toilet we have where the supply line comes up from the floor (the other two toilets - one first floor, one second floor - have supply lines coming in from the interior wall right behind the toilets). No other pipes in our house have ever frozen since we've been here (2011).

I think I've realized that the toilet started freezing during the winter after we got a new boiler installed. The boiler is in the center of the house and vents out (and takes air in) from directly under the bathroom that freezes. I'm attaching three pictures showing the outside of the house where the boiler vent is with respect to the bathroom. Basically, the round tube jutting out of the house is coming from the boiler, and the small window above it is the bathroom window - the toilet is directly below the window, with the supply line coming in through the floor only a few inches away from the exterior wall.

I believe the water supply from the toilet runs along the same pathway as the boiler vent, to the center of the house and into our utility room (which has, among other things, the boiler and the main water shutoff, and lots and lots of pipes). The utility room is 1st floor, smack dab in the middle of the house. So, the boiler vent runs between the first and second floors, right where I think the water supply is for the bathroom.

I don't think the cold extends all that far in, though, because we also have a bathtub/shower and double sink in the bathroom with the freezing toilet. Those have never frozen, but they are a few feet deeper into the warmth of the house than is the toilet.

So, anyone have any thoughts on whether I'm maybe right that something could have been done during boiler install that affected the toilet? Anyone have any ideas on what I can do to stop it from freezing when it gets cold out?

The boiler is a Triangle Tube "Prestige" model, if that matters.

Any help/thoughts/ideas would be greatly appreciated.

Thanks!

 

This may sound a little goofey; seeing as so many people are annoyed by toilets that run continually, when you want them to stop.

Your situation may be one (at least temporarily) where on extremely cold nights, you allow that toilet to run at a trickle throughout the night.

Before moving to Vermont, where our temperatures often get below -40°F, I would have not believed that moving water will not freeze . . . . but I believe it now; and you could be a beneficiary of that fact.

Don't curtail your investigation to find a more conventional solution; but this might take care of a few January or February nights in 2017.

 

Thanks for the idea. I've actually done that and it works. But, like you say, its temporary only.

It took me quite awhile to figure out how to keep the flap open a tiny, tiny bit without going through hundreds of gallons of water. Solution - folded up duct tape; thin enough to not go through too much water, thick enough to let some water thru, doesn't get soggy and disintegrate, and can make it big enough so it won't slip down into the hole (I'm not technical) between the tank and the toilet.

I've also gotten some heat tape that I wrapped around the supply line from the floor to the toilet, hoping that maybe some heat would transfer into the pipe - but that doesn't really seem to work. (I also don't know how good at heat transfer the steel mesh hosing is.)

Anyway, thanks again for the solution, even though temporary. Anyone else have any more permanent solutions?

Thanks!

(PS - obviously at some point, even moving water will freeze. I live near the Hudson River, and that freezes routinely. Depends on how "rough" the water is moving in order to continuously break up ice crystals faster than they can form. Thanks, Mr. Wizard!)

 

Certainly possible that they displaced or removed insulation in that section of the joist bay when they installed the vent/intake for the boiler. I would consider removing a section of the soffit below to inspect the area. Adding insulation, or even filling the area all around the pipe with spray foam insulation could really help. It looks like cold air from the outside may be completely free to surround the pipe, so adding blocking and insulation to prevent that would be a good approach.

 

I agree with CT. If the pipes in question are running through that overhang they definitely need insulation between the pipes and the cold. Also, that soffit area looks to be vinyl or aluminum panels which do not air seal at all. You or someone needs to remove some of those panels and inspect. If as we suspect then insulate and air seal.

What can you see from the basement looking out into that overhang?

Bud

 

CarbideTipped - thanks for the suggestion. When you say fill the area around the pipe with spray foam, you mean around the larger diameter, outside pipe, correct? (To me, it looks like a pipe within a pipe, so just making sure you mean to seal the outer pipe, not the inner pipe.) There already seems to be some clear caulking around the outer pipe, but I don't know how good it is and whether its filling all the holes there. Should I try to get beneath the vinyl siding in order to use spray foam there?

CT & Bud - If I remove the panels and there is no insulation, what type should I use then? Also, not sure what you mean by basement. We actually don't have a basement, just a crawlspace (and I do mean "crawl"!). The windows you see on the floor below the subject bathroom are first floor windows (with the first floor being several feet above the outside ground.) Do you mean what can I see when I'm underneath the overhang, looking up? I don't really see much of anything, just a bunch of little holes in the paneling there.

Thanks again!

 

Actually I meant to insulate the water pipe. You want to prevent cold air from the outside from reaching the pipe. Ideally, you want the pipe to have no insulation between it and the warm inside of the house, and to have lots of insulation between the pipe and the outside air.

You shouldn't have to remove any siding, but may have to remove some of the soffit. You may just find plywood under the soffit, or it may be open into the joist area, which is what I suspect. Somehow you need to gain access to the space where the water pipe runs for that last few feet so you can get it insulated properly.

 

What I was looking for is the view from the crawlspace into that overhang, which may not be possible. But, you said "I don't really see much of anything, just a bunch of little holes in the paneling there." Maybe there is plywood above all of those holes, but if not there should be. I can't see any reason they would use ventilated soffit panels other than decoration.

In the winter a house will experience a stack effect where cold air pours in all of the lower leaks and forces the warm air up and out the upper leaks. This natural air flow can deliver that cold air that is freezing your pipes.

Investigate what is under those soffit panels. If plywood, good, but it will make it difficult to access the pipes.

Bud

 

Bud - sorry, I didn't realize what view you meant. I'm attaching a view of what I see when I am on the ground looking straight up. There are no holes in the panel. It looks like each panel is about 2' wide maybe. I'm assuming I should be able to easily remove the panel right under the vent pipe to see what, if any, insulation is there, right? (The pictures are zoomed in; I'll need to get my big ladder out to actually reach the panels there.)

What type of insulation should I use? Just some foam board between the cold water pipe and the vent pipe? The kind of insulation I've used on hot water pipes to save energy? Just stuff some batt up there? I'm hoping its not cavernous, stretching all the way to the right and left for dozens of feet. If there is plywood there, I probably won't be able to reach the cold water pipe itself in order to use spray foam on it, as CarbideTipped suggested.

Thanks again for all the help!

 

What is that flat circular object on the soffit? A speaker? A light? A vent?

Joists stick out from the house into the soffit (joists run perpendicular to that exterior wall.)

Open up the soffit under the pipe. Reach into the house above the pipe and pull out a few handfuls of insulation from just above the pipe but not too far off to its sides. Rebuild the soffit insulation. Either batt insulation or foam board will be fine. I would not use spray insulation or pour in fill insulation. Put insulation on both sides of the pipe filling the soffit height but leaving a gap about 3 inches wide above the pipe all the way up to the floor above and following/extending the length of the pipe. Put insulation at the far end of the pipe out to the rim joist. Put a good blanket of insulation under the pipe. Close up the soffit.

You do not want a vent under the soffit in the same joist bay as the pipe.

The metal mesh hose has a rubber core. It will not tranmit heat from a heat tape well to protect the pipe under the floor.

 

Hi All,

So I opened the soffit and found the pvc boiler vent pipe had some insulation on the right side of it and above it, but nothing on the left side of it - I'm attaching two pictures (they appear to be rotated so that what I'm calling "left" is "down" in the pictures). Its hard to see, but when I look up on the left side, I can see up about 2 feet to what I'm sure is the flooring of the bathroom above. I can't see the toilet's water pipe because its blocked by either the yellow/white fiberglass insulation or the vent pipe, but its got to be there based on the layout of everything.

So, I'm planning on buying more fiberglass insulation and shoving it up above and around the pvc pipe. There's only a small space on the left side of hte pvc pipe, so is it ok if I just shove a lot of it up there? Or do I need to be careful which side if facing where, etc.? (AllanJ - I didn't quite understand about removing handfuls of old insulation - is that just to see better, or does it make sense to remove some old insulation and then add new insulation?)

(Also, I'm having trouble removing the soffit itself, so I'm going to need to use one hand to pry it down and keep it there while I try to put in the new insulation.)

I'm also planning on getting some foam board insulation (maybe that pink stuff I see sold at HomeDepot/Lowes?) and cutting it to fit UNDER the pvc pipe (and above the soffit). Does that make sense, or should I not insulate UNDER the pvc pipe? If I do put the foam board UNDER the pvc pipe, I can also maybe use some foam spray around its edges to keep it in place. I don't think the pvc pipe gets hot at all, because the exterior portion is the intake, so cold air; the inside portion is where the steam comes out of.

Does any of this make sense at all? Thanks again for any and all help!

 

Yes, I think that's about what we expected you would find. Your plan is fine, just keep in mind that the ideal would be to have no insulation between the water pipe and the warm part of the house, and as much insulation as you can between the water pipe and the cold side of the house. That is so the water pipe gets warmed by the house more than it gets cooled by the outside air. If you have to, you can use pieces of rigid foam to keep the fiberglass from getting between the pipe and the bottom of the floor.

And doing whatever you can to eliminate drafts through that section will help too. If the hole where the PVC pipe goes through the outside wall isn't caulked well, fix that. And well sealed rigid foam across the bottom will help keep drafts out as well. You're right that you don't have to worry about the PVC getting hot.

 

Thanks for the additional advice.

I went to Home Depot today and got lots of stuff, with the intent of returning whatever you guys say to not use.

So, should I use faced or unfaced fiberglass batt? The plan is just to shove it up there - I'm assuming that the cold water pipe is just a few inches below the floor boards up there, which means its a good 2 feet or so over my head - so I doubt I'll come even within a few inches of it with batt...meaning I very, very strongly doubt I'll get any insulation between the underside of the floor and the cold water pipe.

Also, would it be better to put the rigid insulation above the PVC pipe or below the PVC pipe? If I have enough, should I put it both above and below? (I'm not even sure I'll be able to fit it above the PVC pipe, so I guess another question is whether its even ok at all to put it below the PVC pipe - or should I leave out the rigid insulation entirely and just go with the batt?) The Home Depot guy said not to bother with foam spray; rather, just cut the rigid insulation a hair wider than necessary so that I can squeeze it in and it will pressure-anchor itself in. Does that make sense? Its already a very tight space so I'm going to have a lot of trouble if I try to foam spray. (Also, HD guy said if I ever need to work in there again, it will be much easier to not have the spray foam acting as glue - but I suppose I could always easily break through the rigid insulation, right? But then again, I would need to replace it, and there would then be irregular edges everywhere.)

Last question (I hope) - should I remove the whitish/yellowish batt that is currently there and just start all new with what I've bought today? Or can I leave that there and just add to it?

Thanks again, All!

PS - the hole where the PVC pipe comes out through the siding looks very well caulked with clear caulk (it feels like silicone more than acrylic). I guess air could be getting into the hole from underneath the siding though - I don't know if the caulk is just around the PVC pipe and siding, or if it goes through the entire hole - no easy way for me to tell, either.)

 

I suggest unfaced but not a big deal either way. The facing is a vapor barrier and doesn't really come into play here either way. Just putting the rigid below the PVC is fine. If you can wedge it in there so it's tight that's fine. If you have gaps around it caulk may be the neatest way to seal it.

When working with fiberglass, you want the space full, but you don't want to tightly compress the insulation; it works best when a little fluffy. When you are fitting it around obstacles some compression is inevitable, but don't purposefully try to pack it in real tight.


Good luck!

 

Thanks again!

Should I remove the old white/yellow fiberglass batt that's there now and start with all-new pink stuff? Or should I just leave whatever is there now, and add to it?

Also, on second peek, it looks like there may be some romex cabling/wiring going between the joists and over the PVC pipe. Is that a problem for anything I've been talking about or planning on doing?

Thanks!

 

If the old stuff isn't nasty (wet, moldy, etc) you can leave it. If it's easier to neatly fill the cavity using the new stuff, then toss the old.

The insulation won't bother the cables and the cable won't bother the insulation other than being one more obstacle you have to work around.