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Copper pipe frozen leak above unheated garage. Best fix?

Copper pipe frozen leak above unheated garage. Best fix?


Old 01-27-18, 12:01 PM
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Copper pipe frozen leak above unheated garage. Best fix?

In New Jersey:

Genius builder put a bathroom over an unheated garage instead of something else without plumbing.
Nice newish (maybe 20 years) subdivions home. I don't know how that passed inspection.

Guy just had plumber come fix the broken pipe section(s). Then asked me to patch the drywall and re-insulate and said he was looking into possibly heating the garage for long term solution.

The insulation that was there was fiberglass batts on the underside of the copper (between pipes and garage drywall ceiling, but not above the pipes between the floor above, and also I don't think there was insulation on the "side" of the pipe because the pipe runs in an "L" shape and part of it runs along the outer-most edge joist close to the sheathing which could be the cause area and it is where it cracked and flooded), and then over the fiberglass was Reflectix silver bubble wrap fire rated insulation.

I said to hold off on patching the drywall just yet, keep the fauctes/tub above garage on trickle and install temp heat tape plugged in.
Because best I could in terms of just patching it up and re-insulating VS what was already (which already froze) was add foam pipe wrap and then insulation on that "side" area, and possibly above the pipes between the floor and pipes, and to open the rest of the ceiling to insualte the other run of the "L" the same way.

You know insulation works by preventing heat moving to a cold area, not vice versa or anything. So in theory should the pipes even be insulated above them (between the floor of the heated living space and the pipes)? Or is not enough heat passing through that floor to make a difference vs just insulating all sides around the pipes in order to help the pipe retain the heat from the rest of the plumbing line which leads back into the heated living space? In other words, if I insulate above the pipes, it will block any heat that transfers from the heated floor to the pipe, but if I do insualte above it, it will help the pipe retain the heat it had from the rest of the line that comes from the heated living space. That's kind of besides the point though and not what I think would matter much, I guess it would depend on what floor materials were used etc.

FYI, it lasted about 15-20 years until it recently froze but I don't think it should be risked to just try adding a bit more insulation.

I'm guessing the best option would be to cut open the rest of the garage celing and replace all the copper with PEX which is much more freeze crack-proof, and then black foam tubular insulate the PEX and insulate the "side" near sheathing and probably also above the pipes between the bathroom floor and pipes.

Other than that, the options seem like overkill unless I'm missing something?

- Option: Insulate pipes better than they were (can only be slightly better though) and have a ~$4,000 natural gas garage heater installed. But the walls are probably not insulated (I can check today). I've rented a blown-in insulation machine before and it just clogged, and these 10' walls probably have horizontal blocking in each bay and/or wiring etc that would prevent the wall from being totally insulated without making several more holes per bay. In a different situation where the blown insulation just clogged up, I ended up just cutting more holes and stuffing the insulation by hand. But the problem area there was mainly behind a shower wall I didn't want to tare apart. I looked into cutting small plugs out of the exterior wood clap board siding and having a truck-mounted expanding foam insulation come and just pump the stuff and go with no patch work or anything, but they wanted like $1,200 just to pump and go only like eight 8' wall bays. Another option was to remove all the siding and sheathing instead and add foam board (only on the side of the pipes that faced the cold exterior so it wouldn't block the heat from the bathroom). but I ended up using very thick layers of insulated paint (granular sruff mixed into paint) and painting the exterior and it hasn't froze since. Plus there's also a heat cord plugged into the crawlspace below but it still froze but not after the insulated paint was globbed on heavy. Anyway, not to go too off track, but garage heater option would cost about $4,000 for the install, plus need
insulation on two 25'x10' walls which if they're not insulated, and then the cost to run the heater.

-another option is a hot water recirculating pump, but they aren't really meant to prevent pipes freezing pipes unless set on continious or set to run often on the timer. They're mostly meant to have instant hot water. They cost about $600 plus install. Yes they do save water but water is nothing compared to the cost of gas to constantly over work the water heater. Plus if only used in winter, they can seize up in the meantime.

- Do they not make a permenant heat tape that can be sealed in a wall???? I know not to seal the consumer-grade heat tape they sell at home depot/lowes in a wall because a) it only lasts about 3 years and then would need to rip the sheetrock all out again, and b) the change from hot to cold seasons and moisture can cause the outer wire wrap to crack and spark. They do make exterior-grade heat tape for gutters which apparently doesn't crack easily due to Summer and Winter and moisture conditions, but it's not to be installed in a wall. But, they do make electric heat tape-type floro mats that go under tile/carpet which apparently is ok to seal away. But I couldn't find any heat tape that is meant to be sealed in a wall, but if there is, that is likely the best solution.

For now, It just has temp heat tape hooked up with fiberglass insulation put back in and the Reflectix bubble warp tacked over to block draft and no
drywall, and water kept on trickle until a specialist can decide on what approach to take. Who should I even have him call for this? A plumber (I think the last plumber just said "heat the garage" and left), an insulation/energy specialist? An HVAC company?

Thanks in advance.
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Old 01-27-18, 12:33 PM
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Insulation should be between the pipe and the cold zone..... pipe and the garage ceiling. There is no electrical heat tape allowed to be sealed in a wall.

The bath over the garage is fairly typical. Usually the pipes are kept up high in the bay section allowing for better insulation. Going up the outside wall from the garage is like double trouble.

I'm sure we'll come up with some ideas.
Old 01-27-18, 01:26 PM
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"Insulation should be between the pipe and the cold zone..... pipe and the garage ceiling. There is no electrical heat tape allowed to be sealed in a wall.

The bath over the garage is fairly typical. Usually the pipes are kept up high in the bay section allowing for better insulation. Going up the outside wall from the garage is like double trouble. "

There's no pipes in the un-insulated (likely) garage walls.

So you're saying, in theory, it would be best not to even wrap the pipes with insulation tape or black tubular foam, because it will block the heat from above room? I don't think that's make or break the situation though.

I think it will end up being all replaced with pex, and then the pex insulated on all sides.
Old 01-27-18, 08:20 PM
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we/he decided to install an electric garage heater, something like 5000 watts, needs dedicated breaker hard wired, but doesn't need to even be on probably %85 of the winter. And when it is on, only about 35 degrees or something just enough to add like 10-15 degrees because the pipes have only froze on rare coldest occasions. Other houses in development have same issue with plumbing above garage.

I checked and the two garage walls aren't insulated, and no plans to insulate them even though that would eventually pay for itself to need the heater less but it may be decades before that cost is negated.

today I was going to install heater tape temporarily and insulate over it but also leave the ceiling open to not go against the rules of the heater tape, and then like I said, connect him with a plumber/insulation specialist while the temp heater cord was on, but we decided on just installing an electric heater soon and re-insulate it how it was and leave pipes on trickle if it gets really cold.
I didn't even bother installing the heater tape.

- Another option I was thinking would be low cost would be to install the heater tape and re-insulate how it was but then to build a 12 foot hinged access panel so that the heater tape could be inspected and changed out because they only last a few years. The company rep on home depot Q&A etc says you can install them under mobile homes and in crawl spaces, so I don't see why it would be so unsafe to put it in a ceiling bay if it's accessible via a hinged panel. But the thing with these heater tapes that I didn't find any info on until buying a couple today is it says not to insulate more than 1/2" thick fiberglass/black tubular foam over it, otherwise it could cause the thermostat to overheat. That's probably the main reason it simply says "Do not install in walls/ceilings" but it should note that it's likely because of excess insulation in those areas can damage the thermostat.

so the heater tape is a no go. Just going to re-insulate and install heater to use now and then. Maybe it would be more efficient to use the heater tape and an access panel and not cover the heater tape with more than 1/2" of insulation but that just seems sketchy to me.

I still don't understand why they can't just make a quality heater tape that can just be left in a wall. They make mats of similar heater cord that can go under carpets and gets stepped on etc.

as a sort of just-in-case, he wants a 12' access panel under the pipes so in case it ever does happen to break again, no sheetrock needs to be damaged and patched , spackled, primed and painted.

Still dunno how builder was allowed to put plumbing above garage.
Old 01-28-18, 02:02 AM
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too late to edit my last post. Wanted to say a hinged access panel is pointless. if it leaks again, the drywall would still get ruined and would maybe be more work to replace than just a regular patch. Even if plywood/OBS were allowed, that would be worse because it might not show a leak as soon as drywall would, instead water would collect and possibly rot the joists.

No access panel.

Funny thing is now it's back to the original thought of just patch and add a heater.

Maybe he'll figure out later that a recirculating hot water pump would be more efficient than a garage heater but I dunno.

As for replacing the copper with PEX, this line splits into smaller hot and cold likes three times in just 12 feet. So the best the plumber could do is attach 8 copper-to-pex adapters but then those 8 points would still have copper within the problem area. MAYBE the PEX would 'take' that frozen water and harmlessly expand in the PEX like PEX is know to do, but who knows for sure if it's just a waste of effort to change to PEX.

If it were my house, I don't know what I'd do. Probably would already have holes everywhere in the drywall to stuff blown-in insulation because the machine would have just jammed or there were obstacles in the wall bays. Then patch and then maybe add a small oil radiant heater or two or whatever is the safest and least energy usage and on a timer and/or thermostat. But I wouldn't feel safe going on vacation or anything with plug-in heaters running even if they're oil radiant which are considered some of the safest. I'd probably drain the whole frign house so there's no water to freeze lol or remodel the master to not have any plumbing over garage, actually no I probably wouldn't do all that.
Even if it does ever leak again, it's not that big a deal, basically just patch the copper and patch the sheetrock - the leak just flows into the garage with rasied sill plates and then down the driveway. But if on vacation could rot some wood or something especially if it's a pin hole leak and sprays the plywood floor from below which is what this leak did.
Old 01-28-18, 06:17 PM
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I just want to add one more thing about how I was considering the possibility of leaving the bay un-insulated so that the heat from the new heater could better affect the pipes. In theory that would be better but I think it's unnecessary and risky. The heater is only going to be used now and then, so if it's forgotten to be turned on or if it breaks or something, the pipes will freeze much easier, and they have lasted many years without a heater, so the insulation is almost good enough, just have to warm up the garage air a bit (and insulate that side wall of the joist bay better with reflective bubble roll).

also if decide to insulate later, of course wall insulation R13 or greater would be better, but can add an additive like insuladd. Not sure the R value of this stuff but it will reflect heat like a radiant barrier. Also maybe glue radiant faced foam board insulation on already-insulated garage door.

This paint stuff has prevented a problem bathroom from freezing again, painted on heavy on the exterior wall even. so far so good with that bathroom.

Last edited by gunner666; 01-28-18 at 06:54 PM.

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