What pipe insulation for underground?

Old 12-14-19, 04:59 AM
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What pipe insulation for underground?

I have a 1" plastic water line about 3' long that will be running up the side of my foundation wall from inside my trench and into my house, my concern is it will also be about 3' above the frost line. It was suggested to put a 2" piece of foam board against my foundation wall and water pipe and also use a self regulating heat cable, by using this heat cable I would also need to use some kind of insulated pipe wrap. This pipe will be in the ground with back fill around it, can I use a roll of 1/8" foam insulation with foil backing or do they make some other product to use as underground insulation?
Old 12-14-19, 06:10 AM
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Is this a well line?

You bio states NY, I would never install any type of water line that is exposed to the elements regardless of a heater.

Power failure, heater failure, a Polar Vortex winter and you have the possibility of a serious failure!

Get it into the house below the frost line and sleep soundly!
Old 12-14-19, 06:53 AM
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Yes I would not trust heat tapes.
Had two out of three fail after a couple years at the lake.

Sounds like you have no choice but to enter the basement at this spot.
If you have a choice then do as Marq1 says.

I have not done this but is what I would try.
I am sure there are others out there that have done this.
Bury a 6 inch or so thick 3X3 foot or so underground approved styrofoam over horizontally over the pipe then fill over top of it.
This should prevent the frost from reaching the pipe and also trap the heat in the ground and heat coming off the basement wall.
Old 12-14-19, 07:26 AM
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I always bring a water line up into the crawl space, basement or through the slab inside the home where it is protected against freezing. Insulation simply isn't enough. It probably would work most of the time. Unfortunately when you go away for the weekend during winter the pipe has a very good chance of freezing no matter how well insulated. And since winter storms also frequently take out the power I would not rely on an electric heater to prevent freezing.

Extend your trench up to the foundation wall. Bore a hole through the foundation and run the water line into the house below frost depth.
Old 12-14-19, 07:28 PM
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I have concrete floor block wall craw space, the lowest I can come out of my craw space wall is just 1' below ground level. I have 2" foam board against my foundation wall which my pipe will be against and I plan on wrapping it with insulated tape and then put another 2" foam board on the front side of the pipe and also on the sides, kinda like making a box around my pipe down to the frost line. Also putting a 2" piece of foam board flat on the ground over the pipe coming into my wall and another 2' of fill dirt over that, I was going to put heat tape on the pipe just for precautionary measures in case we ever get a super cold winter. Even tho the pipe is going to be inside the foam board box I'm putting around it I also wanted to wrap the pipe in a good insulation wrap for extra protection too, I just wasn't sure which insulation wrap to use. I'm going right up my foundation then 90 it right through the wall, my pipe will not be exposed above ground..

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