Crawlspace treatment

WhirlingD

Hey all… Slightly outside of the box question here…

I have an inaccessible small unseated crawlspace under my very old house, and there are bathroom hot/cold pipes that run for about a foot in this space before coming up into a china cabinet/closet and then straight up to the bathroom.

In the winter, these pipes chronically freeze as they go through this crawlspace.

On the floor of the closet, there is a little trap door, about 16” x 8” that gives about enough room to get your arm in there to reach the pipes around the corner.

My question is: would I be better off stuffing a whole ton of insulation between the ground, which is about a foot down, and up to the pipes… Or would I be better off, leaving the trap door open during the cold season to potentially let warm air from the house migrate down into that space?

I did try to wrap the pipes down there as much as I could with pipe insulation, but it’s hard to get in there, and I don’t think I have anything at the 90° angle.

What do you think the best way would be to prevent those pipes from freezing?

I think I even toyed with the idea of wrapping the pipe, if I could get in there, with some sort of electric wrap stuff and plug it in on the coldest nights. But if I don’t have to deal with all that, I’d rather not, given that reaching in to access the pipes is quite difficult, and I have to wonder if I would even be able to successfully put that stuff around them.

The pipes do come out into the basement as they leave the crawlspace, so I do have access to the pipes just prior to them going through the field stone foundation into about the 18 inches of crawlspace before they go upwards into the closet.

Any thoughts about this?

Thank you! Much appreciated!

Mad Dog_2

Do Both...if you don't want to access it, run the hot and cold fixtures, light stream.. in that bathroom during the real deep freezes...Unless you get down in to Alaskan Deep freeze temps, running 🏃‍♂️ water will generally not freeze.  Just make sure your drains will handle the contstant flow. Also, a plug in  A Hot air blower aimed down on there could help.  Mad Dog 🐕 

WhirlingD

Mad Dog_2 said:

Do Both...if you don't want to access it, run the hot and cold fixtures, light stream.. in that bathroom during the real deep freezes...Unless you get down in to Alaskan Deep freeze temps, running 🏃‍♂️ water will generally not freeze.  Just make sure your drains will handle the contstant flow. Also, a plug in  A Hot air blower aimed down on there could help.  Mad Dog 🐕 

Thanks! So you would stuff that hole with fiberglass insulation? Then, still aims heater of some sort down there? It’s kind of hard to get a heater near there, since there is a bottom shelf of the China cabinet that someone gets in the way. Pain in the arse to access the trap door.

hot_rod

if there is any moisture down there it might be better to use foam insulation. Either cut up some board insulation, the pink or blue, not the white beadboard, or some cans of spray foam

ChrisJ

Where is this location in regards to an outside wall?
How is it getting cold in that location? If you can fix that, you'll fix the issue.


Is there a draft getting through the foundation? That seems unlikely unless it's up near the sill. How much area is there around the pipes where it goes into the basement? Is the basement heated?


Without seeing it, I highly doubt the ground / dirt under the pipes is the issue.

STEVEusaPA

We're in the age of pex. Are you sure you cant reroute, or at the very least pull new piping with insulation on it?

WhirlingD

All good thoughts. Thank you.

The house is 250 years old, and there is a small part of the house that extends past the original foundation, and that is the crawlspace part in which the pipes pass through. That section is likely about 8 feet wide by about 20 feet long, and has no access… And has ground at the bottom, maybe a foot down from where the pipes pass through.

The basement is reasonably warm in the winter, just due to the proximity of the boiler and piping. The crawlspace trap door has very cold air coming out of it when it’s open.

These particular pipes run inside the basement and run perpendicularly through the fieldstone foundation out into the crawlspace. I suppose there’s a way I could get pex in there, but I would have to pretty much chip out the concrete that has been used around the pipes as they penetrate through the foundation. Pain in the butt, but I suppose doable.

Are there pex connectors that would not need a specific tools to connect? Like compression fittings that with link copper to pex?

I’ve been thinking about that, though. I suspect they would still freeze?

ChrisJ

WhirlingD said:

All good thoughts. Thank you.

The house is 250 years old, and there is a small part of the house that extends past the original foundation, and that is the crawlspace part in which the pipes pass through. That section is likely about 8 feet wide by about 20 feet long, and has no access… And has ground at the bottom, maybe a foot down from where the pipes pass through.

The basement is reasonably warm in the winter, just due to the proximity of the boiler and piping. The crawlspace trap door has very cold air coming out of it when it’s open.

These particular pipes run inside the basement and run perpendicularly through the fieldstone foundation out into the crawlspace. I suppose there’s a way I could get pex in there, but I would have to pretty much chip out the concrete that has been used around the pipes as they penetrate through the foundation. Pain in the butt, but I suppose doable.

Are there pex connectors that would not need a specific tools to connect? Like compression fittings that with link copper to pex?

I’ve been thinking about that, though. I suspect they would still freeze?

Can you build a box / duct out of 1" thick +- construction styrofoam board into the basement and insulate the pipes from the surrounding area? That would allow heat from the basement in and keep the drafts away from them.

bburd

The problem is most likely those cold drafts.   Insulation doesn't generally make a good draft barrier unless it's inside an airtight box as described above.  Fieldstone foundations are notoriously drafty.

The best fix would be to run new PEX entirely inside the heated part of the house.

EBEBRATT-Ed

I agree with @ChrisJ

Build an insulated box around the pipes. Then put a grill in the floor to let some heat into the box. Maybe some heat tape in the cold weather in addition to the box

Mad Dog_2

Or...bite the bullet, open some walls and reroute water lines in to conditioned space. 
Its not as bad as you think.  You're going to spend alot of time Gerry-Rigging this...AND YOU STILL GET A FREEZE UP! Mad Dog 🐕 

Jamie Hall

The cold draughts are the real problem, as noted -- however, if you can get hold of a 100 watt incandescent bulb (good luck, they're illegal now, but just maybe...) you can leave that in there, running, and that probably will do it.

STEAM DOCTOR

Be careful with how you insulate. Done incorrectly it could really be reversed insulation. Meaning if the insulation is between the heated part of the house and the pipes, then you are making things worse not better.

ethicalpaul

Or...bite the bullet, open some walls and reroute water lines in to conditioned space.

And so easy with Pex, right Matt?!

however, if you can get hold of a 100 watt incandescent bulb (good luck, they're illegal now, but just maybe...) you can leave that in there, running, and that probably will do it.

Until it burns out one winter night and you don't check it that day

Mad Dog_2

Yes Paulsy! It IS easy for a PROFESSIONAL plumber in Copper or PEX...And, what IS your actual profession, besides Armchair QB, Contrarian, doubting Thomas, and Naysayer???? Please do elaborate?  Mad Dog 🐕 🤣 

Erin Holohan Haskell

@ethicalpaul and @Mad Dog_2, please stop antagonizing one another.

mattmia2

If you can access the pipes through the trap door you may be able to slip the adhesive flap kind of k-flex pipe insulation on the pipes and slide it down and up to where the pipes go through the floor, or maybe even use the next bigger size. it is about 50/50 if you will be able to get it to slide around the corner and up to where they go up in to the structure. Of course this will just help you if they freeze occasionally on the coldest day, if they freeze for a month starting in January then you will need something more.

Mad Dog_2

Absolutely Erin!  Only defending myself.  I will ignore him from here on in. Mad Dog 

gmcinnes

How hard is it to lift the floor there to access them? I assume difficult, since you didn't mention it as an option?

Others are right. Stuffing fiberglass won't do much. If there's a draft it will pass right through. It's like a woolen sweater on a windy day. The wind passes right through it. You need a windbreaker in conjunction to make the woolen sweater useful.

You can get long commercial spray foam nozzles, and flexible ones that would be able to reach the length of your piping, but it would be kind of a hope and prayer that it actually wraps the pipe. Hard to insulate what you can't see. And if it fails and freezes, well, now you've got two problems.

Good luck!

ethicalpaul

Mad Dog_2 said:

Absolutely Erin!  Only defending myself.  I will ignore him from here on in. Mad Dog 

The last thing I'm going to say on this topic is that for months you have made personal attacks against me apparently because you don't like some of my ideas. I have occasionally needled you in response as in above, but I have never attacked you personally as you have done me, repeatedly.

It's a shame because when you first returned to this forum, you were quite complimentary of some of my posts, but something seems to have changed, I don't know what. It's also a shame because we share quite a lot in common, such as my father too was a lifelong horseman--first a jockey, then a farrier, then a manufacturer of horseshoes.

Anyway I wish you well. I am a software engineer by trade, to answer your question.

Erin Holohan Haskell

One of the things that makes this site unique is the range of knowledge and perspectives of our community members. We're not always going to agree on everything, but there's always something to learn. Nitpicking at one another erodes at the good work that we're doing here. It also really annoys the site admin. So let's move on, respectful of site rules and of one another. Thank you.

Now let's get back to talking about crawlspace treatments. Sorry we got off track @WhirlingD.

WhirlingD

All good ideas, but no good answers… Thank you, Erin for moderating.

The floor in the closet/cabinet is pretty old plank, flooring, and it likely goes right past the wall and into the kitchen. I’d have to cut it out of there, which I doubt I’ll do.

Love the idea of trying to get the pipe out of there, but that’s a much bigger job.

I did have a bunch of fiberglass insulation packed in there as tight as I could around the pipes, from the ground up, and I think I noticed a difference, but it’s hard to say because I always left the water dripping on the coldest of nights in the northeast US, and often left the door and the trap door open, just in case.

I have already had two burst pipes in there over the last 15 years… One I fixed myself, and one continuously failed, so I called a local plumber. Ughhh…

ethicalpaul

You were probably packing the fiberglass tightly in order to limit air intrusion. Limiting cold air intrusion is a great idea, but I think fiberglass insulation is the wrong tool for that.

The tighter you pack the fiberglass to limit air flow, the worse of an insulator it is.

Injected or spray foam, as others recommended, will kill the air intrusion and also is an excellent insulator.

WhirlingD

I should probably clarify… I wasn’t compacting the insulation… Just trying to take up all the space… :-)

Maybe what I should try to do is put the insulation in there around the pipe, but leave open space between the pipe and the trap door.

I don’t think I have the means to do a lot of spray foam insulation. I suspect that would get expensive.

Mad Dog_2

All is forgiven. Water under the bridge 🌉.   Amen, Erin.... Peace Paul....Mad Dog 

Jamie Hall

I still like my lightbulb... there is another possibility, though, which isn't quite as absurd as it sounds: arrange some way to have a recirculating option and keep the water flowing at all times. I'll have to think about how that might work without installing any more pipes in the crawlspace... oh. One way would be to put a small intant hot water heater in the bathroom, and repurpose the hot water pipe as a return line. Then a small pump in the warm basement to recirculate, maybe even with a tempering valve to pick up enough hot water from the main house system to hold the bathroom water at, say, 50.

HVACNUT

Jamie Hall said:

I still like my lightbulb... there is another possibility, though, which isn't quite as absurd as it sounds: arrange some way to have a recirculating option and keep the water flowing at all times. I'll have to think about how that might work without installing any more pipes in the crawlspace... oh. One way would be to put a small intant hot water heater in the bathroom, and repurpose the hot water pipe as a return line. Then a small pump in the warm basement to recirculate, maybe even with a tempering valve to pick up enough hot water from the main house system to hold the bathroom water at, say, 50.

My wife just painted our kitchen ceiling so I removed all 10 LED Hi Hats and brought her my lamp post with 2- 500 watt halogens. She's now got a nice base tan and still can't see straight. 

SlamDunk

I agree with @Jamie Hall regarding a lightbulb. It will work. Incandesent bulbs are hard to come by. For my chicken coop, I use a couple 100watt ceramic heaters. Screws into regular bulb socket.

https://www.amazon.com/LUCKY-HERP-Ceramic-Reptiles-Amphibian/dp/B096JWWQMC/ref=sr_1_1_sspa?hvadid=598922572967&hvdev=c&hvlocphy=9009733&hvnetw=g&hvqmt=b&hvrand=15467576516285708440&hvtargid=kwd-303910982555&hydadcr=16853_13458203&keywords=ceramic+coop+heater&qid=1691191135&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1

I was going to suggest a hotbox heater often used to protect back flow preventers from freezing. Or, an oil filled electric radiator. You only need to keep the space above 32 degrees.

https://www.supplyhouse.com/Qmark-WHT500-WHT500-Utility-Well-House-Electric-Heater-500-376-500W-240-208-120V?utm_source=google_ad&utm_medium=Shopping_ntm&utm_campaign=Shopping_NTM_New_users&gclid=CjwKCAjww7KmBhAyEiwA5-PUSn8PiWldwTHv3e41QkGwuJwoVmKbSYMCATDdvUMjLS4bWma-04s8rBoC44EQAvD_BwE

Mad Dog_2

Do they still make Infrared light bulbs?  We used them on the Racetrack in the stalls during the winter.  It was amazing how much heat they put off from a standard 110  Volt socket...Mad Dog 🐕 

Jamie Hall

Mad Dog_2 said:

Do they still make Infrared light bulbs?  We used them on the Racetrack in the stalls during the winter.  It was amazing how much heat they put off from a standard 110  Volt socket...Mad Dog 🐕 

I think you can still get those -- heat lamps. They really are amazing.

Mad Dog_2

They kick off some BTUs..mad dog 🐕 🤣 

ChrisJ

What about heater tape wrapped around the pipes with a built in thermostat?

JUGHNE

I did come across a list of still permitted incandescent light bulbs, I was surprised by the fact that some common sense and logic was applied to the list.
Rather than a solid across the board mandate of removal.

They included:
Appliance bulbs
Infrared bulbs (I always had vision of dead baby chicks under a LED )
Black lights....for old hippies?
Grow lights....for young & old hippies?

Then, bulbs with left hand thread.....has anyone seen any of these?

There were a few more oddities on the list.

Eventually the compact fluorescent will go to the chopping block.
( I never liked the looks of the pigtail ones anyway).

Our little church is loaded with the pigtail ones of fairly high quality.
They will be there a long time as the usage is 2-3 hours per week.

I thought some in the back had failed but found out they has been unscrewed.
Why??....because they produced a quite white color of light and for a funeral viewing that color made the person in the coffin look, well, dead.
And anyone standing there had the same pale complexion as the deceased.

So the mortician took it upon himself to unscrew 2 of the 3 lamps in the hanging fixture to make his work look better.
In the funeral home they have 2 large floor lamps next to the coffin that give a red, more alive, color to the customer.

MikeL_2

       I suggest opening the fieldstone to allow warm air from the full basement to get in to the unconditioned space. In homes with forced air heat, I've routed a small duct through drilled holes in stone. A small fan can serve the same purpose. 
        Pipe wrap insulation is good for preventing condensation, maintaining water temperature, and reducing velocity noise; insulation doesn't create any heat so it may not keep a pipe from freezing in an uncondtioned space.
          I don't think heat tape is safe to use in an inaccessible area, and it won't help during a power outage. 
     And always be careful when using a dripping faucet to prevent freezing; it invites a whole other set of unintended consequences. 

Mad Dog_2

Yes..Left Handed bulbs used on construction sites, so the guys don't take them home.  Mad Dog 🐕 

WhirlingD

Interestingly, about 10 feet away, there is an opening that leads under the kitchen… That was the size of a basement window… Maybe 24” x 12”… And it was boarded up with a piece of plywood and insulation blown in around the edges…

We had an unusual cold spell up here in the north east US, and during that time several pipes in that crawlspace, froze and burst, so I had to get access to that portal to have those pipes fixed and changed out to pex.

When they were down there, I asked the heating company who is doing the repair what I should do to prevent further difficulties, and they suggested just keeping that portal open so that the warmer in the basement could go in there… I figured the freezing air from underneath there would get into the basement, which it probably would, so I will have to see this winter if it makes any difference down in the basement, which could have an effect on the air that migrates upstairs as well, who knows.

I hate to start messing with a Fieldstone foundation though, but it might just be a matter of trying to drill out some old concrete that’s around the pipes (without actually destroying the pipes… :-). Not sure that would be enough space around the pipes to allow adequate warm air in there.

MikeL_2

   A small fan in that 12 x 24 opening during bitter cold weather would work well, especially if you make another opening near the piping.
   As someone else mentioned, finding & sealing the source of the cold air infiltration might solve the issue. The problem may be able to be addressed from outdoors.....