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heat tape for water pipe in unheated garage?

Posted by bibbus (My Page) on
Sun, Mar 9, 14 at 20:27

So for years, I didn't keep my heat turned on when I was away from home on trips during the winter. My house is very well insulated and the winters have been pretty mild. But this year I did have my heat on but a freak incident resulted in my heat pump being turned off the night before we had 0 temperatures. It stayed off for three days until a friend got in to turn it back on. The temperature didn't get above freezing for those three days. The pipe that froze was in the ceiling of my unheated garage (stupid construction). The plumber who repaired it recommended wrapping the pipe with heat tape and adding a thermostat. He will charge me $600 to install 30 feet of heat tape - total cost for parts and labor. Do you think I need the heat tape knowing that I likely would never accidentally turn off my heat again and that winters are not likely to be as cold as this year again. Or is $600 a good investment just in case. Thank you.


Follow-Up Postings:

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RE: heat tape for water pipe in unheated garage?

Heat tapes that I've used have a built-in thermostat and you just plug them in. I'd put an outlet in the area so an extension cord would not be needed.
JMHO


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RE: heat tape for water pipe in unheated garage?

$600 seems steep for that... and you are correct, it is stupid construction.

Do you have a home alarm system?

My alarm is set up to notify the monitoring company (and then they notify me) if the temp in the house hits 40 degrees.

The heat tape in the garage doesn't help the rest of the house if the heat is off and it gets below freezing for an extended period of time.


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RE: heat tape for water pipe in unheated garage?

Does that $600 include drywall cutting and repair, bringing electrical into the area? If so it probably accounts for the different trades, each one is about $100-200 minimum for a visit. If it is already open you can easily wrap it yourself for significantly less and leave the plug end easily accessible for an extension cord that you just have to remember to plug in, especially if you turn it off when you leave. You can always get an outlet installed later closer by if you wish.

After my basement was finished and the basement heat no longer leaked out under the slightly overhanging first floor, our first floor kitchen sink pipe froze when temperatures dropped. My basement renovation contractor came back and wrapped the pipe with the heat tape, plug end accessible from under the overhang. I just plug it in during my late fall cleanup and unplug it every spring. The pipe turned out to be readily open to the elements before he added batt insulation and plywood cladding under the overhang.

The heat tape warms the pipe water enough that I have to run it a bit in the winter to get cold water even on the coldest days (no thermostat) . I therefore don't think that you have to wrap all of it, just the part in the colder part of the garage.

When we were on vacation during the polar vortex with temperatures in the 0-10 degree F range outside, our oil tank ran out of oil and interior temperature of the house was 38 degrees F when we arrived home. Fortunately the electricity was still on to power that heat tape and none of the pipes had frozen or burst.

HTH


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RE: heat tape for water pipe in unheated garage?

That is a good idea. I can do it myself although I don't have a ladder that is high enough. The price does not include anything but the cost of the tape and the extension cord. So I could also get the company that Is going to do the sheet rocking to wrap it for me. There is an outlet fairly close by.

Jake, I don't have an alarm system in this house but what a great idea.


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RE: heat tape for water pipe in unheated garage?

Bibbus,

the materials might cost you $50-75 for the heat tape and cord. You could more than afford to buy a ladder and still save a lot of money.

BTW: there are auto-dialers if you have a land line that can simply call you or a list of people if the temp drops in the house or power goes out.

I have no connection to the business below other than I've used them before.

Here is a link that might be useful: Freeze and power loss alarms


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RE: heat tape for water pipe in unheated garage?

Pipes freeze in uninsulated walls when the temperature outside gets to 20 or below. I suspect we waste a lot of energy and $$ fretting about 30 - 40 degree temps, or "below freezing".

My house has two wings, but I only use one of them in the winter. I keep the heat turned off at night unless it is below 20 outside. Then I turn the heat up a bit and I have a space heater on a thermostat, set to 50 degrees, in the bathroom. I've had no problems.

Can also drip faucets to protect pipes.

You could also isolate that one pipe so you can drain it for when you're away.


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RE: heat tape for water pipe in unheated garage?

So, since the pipes burst, I have been turning the water off in the house and draining all the faucets. Are there any unintended consequences to turning the water on and off? I'm gone from the house for weeks at a time. After April is behind me and hopefully the repairs completed, I won't need to do that.


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RE: heat tape for water pipe in unheated garage?

Only downside is the cost of the plumber to drain the pipes for you. But with heat costing what it costs now, it might be cheaper to drain the pipes! Make sure toilets are drained as well, and if frigid temps are expected, you want to run some RV anti-freeze into the washing machine.


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RE: heat tape for water pipe in unheated garage?

Btw, turning the taps on to empty the pipes isn't enough. You have to have a plumber blow them out so they are completely empty.


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RE: heat tape for water pipe in unheated garage?

We have a tankless heater mounted outside on the wall. I wrapped the pipes below the heater with a heat tape and insulation. Typically I plug it in around the first freeze and unplug it now-ish (March usually being last freeze in GA). The tape is only about 5 feet long.

You want to use a self-regulating tape. Basically, the higher the temperature, the less heat it puts out. The concern is that a non-regulated tape (aka "constant wattage") could overheat and start a fire.

When I specify heat tracing for industrial plants for work, my company's standard is to use both a thermostat and a self-regulating tape. It's a belt-and-suspenders approach, but it also minimizes the power usage when you have lots of heat-traced pipe, as well as the potential for a failed cable to cause a fire. Personally, if you have a pretty long run through your garage (thinking 10 to 20 feet, not sure if both hot and cold water), I'd get a thermostat too. It will cost more, but that's what I'd do for a longer run of piping.

McMaster Carr and Grainger are the two places I look for off-the-shelf parts. McMaster will provide the cable to the length you want, and a quick look made me think Grainger had a less-expensive thermostat. That said, Amazon seems to have most everything too. FWIW, Raychem is the typical heat trace cable manufacturer.

On draining your pipes, it depends on what the pipe arrangement is. My house has a crawlspace, so the water line comes in there and then distributes up to the house. There aren't any up-over-and-down runs like it sounds you have. There's a chance you could cut in one or more drain valves and get all of the water out, but it's pretty specific to your layout.


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RE: heat tape for water pipe in unheated garage?

So I realized that the only time I might again have a problem with this water line is if I lose power. Then the heat tape won't help. So I'm leaning toward not even installing it.

As for the set up of my water pipes. I have a three story house in a large subdivision. The water comes in through a closet in the entry way and it has a handle shutoff. There is a half bath right next to where the water comes in. The water line goes above the ceiling in the entry way, out through the unheated but well insulated garage ceiling (which is also under the obviously heated living room) and then turns to go back inside the heated part of the house. The house is VERY well insulated.

I did flush the toilets to remove as much water as possible but it didn't get all the water out. But unless I lost power the heated parts of the house wouldn't be a problem.

So am I pretty safe in just turning off the water and draining all the faucets and toilets to make sure the water is out of the one water line that goes into the unheated garage? And I still have the question if turning the water on and off maybe 3 times a year during really cold weather when I'm traveling in case of a power outage does any damage. Or if turning the water off is no big deal. Thanks!


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RE: heat tape for water pipe in unheated garage?

Turning the water off is no big deal.

Empty pipes can't freeze, so if you can empty a pipe that is more vulnerable, do it.

The pipes you have to worry about most are those on outside walls. Unless there is a deep freeze for three or more days, you don't really have to worry about pipes that are on inside walls.


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RE: heat tape for water pipe in unheated garage?

A pipe that is 90% full will not burst if it is frozen.

http://www.spokanecounty.org/data/buildingandplanning/disaster/DIS-FreezeBurstPipe.pdf

Here is a link that might be useful: Freezing pipes


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RE: heat tape for water pipe in unheated garage?

The thing is if you turn off the water, at least you won't have the water damage should a pipe freeze and break.

It's a reasonable thing to do if you are going to be away in the winter - just shut off the main.

Look into one of those power/freeze alarms if you have family or neighbors that you wouldn't mind calling to check on the house if need be. They seem like a cheap way of getting peace of mind if you are away for extended periods during the winter.


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RE: heat tape for water pipe in unheated garage?

Definitely if you can cut off the water and drain the lines somewhat, that's going to be cheaper/simpler than heat tracing.

It sounds like your half bath could be a good point to drain to. Once you cut off the main line coming in, open the faucets in the upper floors then open the faucet in the half bath. The upper floors will serve as vents to allow air in to drain to the lower outlet.

There may still be some kinks in that method, and it doesn't address the hot water side. But hopefully you get the idea as a starting point.


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RE: heat tape for water pipe in unheated garage?

Thull, What do you mean about not addressing the hot water side? I drain both the hot and cold water. Is that not really draining it?


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RE: heat tape for water pipe in unheated garage?

The way you described the cold water side made it seem like it's a relatively-simple arrangement that would drain back to near where the line first comes in from the street. I wasn't sure the hot water did the same thing. You still want to find a low point and drain from there.

Note that what bus_driver says is true, but if there's a low section that's totally full, it could still freeze and break the line.That's more likely to be the case than a line being partially filled.


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RE: heat tape for water pipe in unheated garage?

Listen, I wouldn't worry too much about draining the lines.

Although I've seen that theory about water lines breaking because of water pressure... I've never known that to work that way in practice. What I've seen is pipes (and traps and toilet bowls - which according to this shouldn't break) break where the ice has expanded in width - just like a beer bottle in the freezer. Virtually every home has a pressure release valve on the water heater - which would take care of any upstream water pressure event that could burst a pipe. Many sinks are plumbed with PEX supply lines which should break before a metal line... again - I've never seen it work like that.

That said, let's keep in mind what we are trying to do and the odds of it happening:

If you turn off your water main - you will not have a waterfall in the unlikely event that your heat shuts off for an extended time in extremely cold weather (also pretty rare for your area). That mitigates the most expensive and damaging possible outcome of those two unlikely events.

Beyond that, you really can't evacuate the contents of the plumbing well enough to prevent a pipe break without going through extraordinary measures -- which isn't reasonable to do given the unlikely occurrence of the two factors.

Purchase a freeze and power alarm - $50-75 if you are worried about it while you are gone.


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