Heating Tape Question

[Kruse]

Hello All,

I have a plumbing question I hope I could get some advice on. The situation is I am fixing up an old house. There are two houses on the same property and the the water comes from the street, into the larger house (where the main shutoff and meters are), and branches off to the second house. The pipe goes underground, beneath the frost line to the second house. Once it gets to the house, it comes up from the ground, runs about 9 feet under the floor, then to the sink where it branches off to the hot water heater and cold water for the rest of the house.

The problem is it always freezes at some point during the winter at the part where it comes out of the ground and runs under the house. The space between the ground and the floor is only about a foot high and inaccessible unless the floor is torn out, like it is now.

I've had a few people tell me to put a heating tape on the pipe, like the kind you buy at Lowes or Ace with the thermostat, and put a plug under the sink/cabinet area. My thinking is only a crazy person would put a heating element in a confined, inaccessible place like that. I'm worried about mice and moisture having a very negative effect on it. They say I'm crazy, I say they're crazy. So would it be acceptable to put a heating tape, with insulation, on this pipe?

The crappy part is I think I'm screwed either way: if the pipe freezes and bursts or if there is a problem with the heating tape because I would have to tear the floor up again. Although I'd prefer a bust pipe to a potential fire.

 

[Mac]

Firstly, welcome Kruse!

Maybe you are screwed either way. Is it possible to eliminate the exposed 9 ft horizontal pipe, and have it go straight up into the house? Then the area exposed to the cold is minimized, although it would still need some means of freeze protection.

Is there a heat duct anywhere close to the pipe? Can the pipe can be run close to a duct?

While you are rebuilding the floor, add a trap door crawl space access hatch.It would make it easier to check the heat tape!

 

[globe trekker]

Welcome Kruse to the Building Codes Forum!

Can you change the type of potable water piping to pex? Pex seems to be more flexible /

durable / forgiving in temperature related conditions. Also, double wrap securely and

completely the pex with an approved type of foam (type) insulation.

Also, not a fan of any heat taping. I would not recommend it to my clients! Too

complicated and restrictive space to be installing and maintenancing.

.

 

[tmurray]

Could you make anywhere the pipe runs part of the heated space? As in to box it in and add insulation on the exterior of the pipe while removing insulation from any adjacent heated spaces.

How cold does it get where you are? Where I am in Canada we require 37mm (1 1/2") SM Foam coverage for each foot closer to the surface than 1800mm (6').

 

[Kruse]

Thanks for the warm welcome everyone.

From your responses I'm thinking I need to get rid of that horizontal part. What if I connected the pex (I had to google that) to the copper below the frost line where it comes out of the ground. Do you think I could run that vertically into the house and along the base of the wall. Then cover it with some molding? I would have about a foot of exposed vertical pipe beneath the floor, but I could insulate that well. I'm in Pennsylvania, so it does not get extremely cold often, but when it does that dang pipe freezes.

 

[Alias]

I have heat tape on the water supply line entering the house. I also have a 3' crawlspace accessed from the outside and I can crawl under my entire house. Temps here can reach -20 F at night and a balmy 0 - 5 F degrees for daytime temps for a week or more in the winter.

I will agree with you and I would not put heat tape on a water supply line that has less than a 2' crawlspace. From my standpoint (not code), I want this accessible so that I can do monthly/yearly inspections to verify that there haven't been vermin chewing on it. Pack rats, kangaroo rats, & deer mice are common where I live.

I will suggest that you insulate the lines both with foam pipe wrap and, if possible, a layer of insulation between the crawlspace and the pipes. Also putting down a vapor barrier such as visquine over the dirt helps to prevent moisture and retain heat lost through the floor. It is required here when building a new home that has a crawlspace. Welcome to sunny CA.

 

[Alias]

Thanks for the warm welcome everyone.From your responses I'm thinking I need to get rid of that horizontal part. What if I connected the pex (I had to google that) to the copper below the frost line where it comes out of the ground. Do you think I could run that vertically into the house and along the base of the wall. Then cover it with some molding? I would have about a foot of exposed vertical pipe beneath the floor, but I could insulate that well. I'm in Pennsylvania, so it does not get extremely cold often, but when it does that dang pipe freezes.

Kruse -

Welcome aboard.

What is your frost depth? We go 18" below ground here due to the weather conditions.

I am not sure that you can use PEX in an underground situation. I would check with the manufacturer for more information. Anybody else here seen PEX used underground? I've only seen it above ground but then, I'm in CA and we're different..........

 

[globe trekker]

Table P2904.4 ( from the 2006 IRC ) allows PEX to be installed as water service pipe,

underground.

.

 

[Alias]

Table P2904.4 ( from the 2006 IRC ) allows PEX to be installed as water service pipe,underground.

.

globe trekker -

Thanks for the reference. We're using the CPC based on the UPC (IAPMO) here, hence the comment.

 

[globe trekker]

My mistake Sue! I keep forgetting that you are using the CPC! I am not familiar with that

code.

.