My daughter lives in a old trailer home. Last year the city ran in new water lines. Before the park was on a well. Anyway the old water line came in right under the bathroom so from ground up to bottom had short heat tape on it.. I've been doing some work on her bathroom basically remodel.. So crawling around under trailer for first time messing with water shut offs and such.
Now this new water line comes out of ground on opposite side of trailer. Lays across ground underneath trailer and then comes up to floor below bathroom. Last winter it got down to like -20 for a while and they let water drip in bathroom only had freeze maybe one or two nights.. They thought they just needed new heat tape..Tape I found under there is not even hooked up to new pipe.
What I'm wondering is how best to insulate or should I put new heat tape on that main line. Iine has foam pipe cover on it now from where comes out of the ground to floor of trailer. I'm wondering should I put heat tape on it again? over or under foam? or maybe it would be ok to just put some foam board under pipe and fiber glass bats over it let ground heat it??? I've never messed with that kinda thing so really got no idea.. I can get some 1" bead board foam and six in glass bats for nothing. Seen as they only had a problem last year when it was the -20 something days. I'm thinking it shouldn't take to much to keep it from freezing..
What do you guys that got lines out in the cold all winter think would be best?? I recall my parents piling hay over the line from the old well house to the side of the house.. This line is under the trailer getting some heat from above, so not right out in open ground. I'm not going to pile hay over it but not sure putting glass bats over would help or hurt?? I know nothing about heat tapes.

I'm open to ideas

Mac

When I lived in Idaho, I had to cover heat tape with glass/foil wrap to prevent freezing,
Wiser to invest a lil $$, to avoid a major inconvenience......ie, what if the heat goes out so its not heated at all under there?

foam board under the pipe( helps keep moisture off pipe). heat tape directly on pipe. pipe insulation on pipe.fiberglass batting over everything. this helps keep drafts from robbing your heat.

What kind of pipes ?? Steel, plastic, copper ???

Depending on how long a run it is......I would consider boxing it in and lining the box with foam board......hopefully there are no joints in that run.

Heat tape can burn out when you need it most. Also, be careful putting heat tape on plastic pipe. An incandescent bulb works well as a heat source if the space is small. They too can burn out when you aren't looking

Every heat tape I've ever seen say's "Do not put insulation on over the tape".

One trick I've learned to prevent pipes from freezing , make ice.

Sounds weird , right ?

On real cold nights , most people will tell you to keep a faucet dripping , yes that helps.
Do that , because flowing water doesn't freeze that easy , true.

In addition to that , if you have a refrigerator with an automatic icemaker , dump the tray/bucket out.
This way in addition to the dripping/flowing water your icemaker will cause the water to go full stream to fill the icemaker tray every 1/2 hour or so. Just like someone turned the tap on every 1/2 hour or so.

Only works until the bucket is full , unless you dump it again , but will get you through those really cold nights.

A more permanent solution like heat tape or installation etc is better for the long term , but this will help and costs very little to do until a better fix is in place or if you live in a super cold climate and may need something extra on those frigid nights.

Thats the best tip ive heard about anything.

Most heat tape is undependable. The good stuff https://www.mcmaster.com/heat-tape is pricey and requires an expensive termination kit. But, it's self regulating. It can be installed under insulation and won't overheat, even if you overlap the tape.

The way we do it on exposed water lines for cooling towers is to wrap heat tape around the pipe and then insulate the pipe with split foam pipe insulation. Fiberglass insulation gets wet and won't insulate any more once it's wet.

I sleeved my pipes under my home. Meaning my 3/4 inch water line was heat taped then put inside a 3 inch drain pipe, elbows and all with 3 inch elbows. The open ends where the pipe started and ended going into home I packed with 6 inches or so fiber glass mat. works like a charm, heat tape has indicator light at plug, if it is on tape is working. Remember everything wrapped around a pipe that is froze keeps it froze when trying to thaw them. I figure I can pull out the fiber glass and use a heat gun in the sleeve to warm the inner pipe like a heat duct. My crawl is sealed well and my furnace blows a small amount of heat under home.

This link is to a product we used on cattle and hog waters all the time you would have to have some type of box, but we went to using just these instead of immersion heaters, we would wrap them so they touched the plastic valve and waterline most of ours would last 3 to years in a nasty environment, and like white said a incandescent light bulb puts out a lot of heat.

https://ritchiefount.com/product/self-regulating-heat-cable/

Thank You , you made my night

oops, that's what I meant to say, NOT glass foil wrap.....been 30 yrs since my Idaho days.

Another tip.

If you go the heat tape method , do what I've done with my waterbed. (remember them...lol)
As I have been thru a few waterbed mattresses over the years due to leaks etc , I have a total of 3 heaters under the mattress. The reason why is I've accumulated them over the years from buying new mattresses and gotten them from friends. I have all 3 under the mattress because it is a good place to store them (only 1 is plugged in) and if one fails , just plug in the next one without draining the mattress to do it.

Most heat tapes require you to install them straight along the pipe , no wrapping. If you have to do the 'commando crawl' to install it , use a quality product and install more than one. Labor costs are high when doing this even if you are doing it yourself. If one heat tape craps out , plug in the next one.

We put heat tape and the driscol pipe inside insulated arctic pipe. (just insulated sewer pipe) Then build a foam insulated wood box. Have the heat tape run to it. Use screws so you can take it apart if needed. stuff it with batts.

I like the ice maker Idea but daughter don't have one and I'm not installing one for her.. Be kind of the same idea of just not jiggling the handle on the toilet when it does that little flow thing they do sometimes LOL!
I got some ideas from you guys still not sure which way I'm going to do it until I look at it again. I really don't know if the pipe is PEX or PVC or copper? I have to say it'a wrapped in foam now so I got no idea. Being where it is I assumed it was copper?? Is about maybe 10ft run where comes up out of ground goes up into floor..I'll figure it out so I'm doing more than raking leaves over it of bails of straw..

Thanks for the ideas guys..

Mac

Problem with heat tape is you find one failed when a water line busts. The other problem is it works good and under a trailer there are not any better options I am aware of. I don't know anybody that lives in a mobile home who doesn't have trouble every few years with frozen water lines. Especially after a freezing rain that knocks out power for several days. When you have to replace that existing line pex can take a lot of freezing without bursting.

Have been there done that ! Learning from the past . Now live in a " DRY CABIN ". Life is Good .... Tut

I have found that none of the heat tapes recommend being installed behind closed walls. Hope its Pex pipe which is forgiving if frozen. Insulation works both ways once a pipe freezes it keeps out the heat. As far as water dripping its better to have it running at a pencil size stream, dripping does not always work a good stream of water works almost always.

The way the crawlspace is under our house is, the vents allow you to see if the lights are working on your lamps.

When I lived in a shoe box, we had a heat tape with an indicator light on it, that was wound around the plastic water line and that was wrapped with 2 layers of glass insulation and the plastic wrap around this. The skirting kept all drafts to a minimum and our pipes never froze. One trailer I had the water line hung from the frame with conduit clamps and beam clamps to keep it close to the floor and off the ground. That one ran 2/3 the length of the home.