Hot Topics: Shower Won't Turn On - Frozen Pipes?

blue pipe frozen over with small icicles

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Original Post: Shower won't turn on - frozen pipes?

rktrump - Member

My shower won't turn on. I have a single handle that works both the hot and cold water, and nothing at all is coming out.

I used the shower about 12 hours ago with no problem. The bathroom backs onto a freezing cold garage with nothing but insulation and drywall protecting it from the single-digit temperatures for the last week or so in Baltimore, MD.

The toilet and the sink in the bathroom, which are just a couple feet from the shower (closer to the warm part of the house and the hot water heater) are working fine.

My question is, could this be a frozen pipe situation? What are the odds that both the hot and cold water pipes froze solid within 12 hours (granted, in very cold weather) just feet from where they're currently working fine?

There's no way to get to the pipes behind the shower without tearing out drywall in the garage, which I worry sets us up for greater likelihood of the pipes freezing over back there, whether or not there's a currently frozen pipe.

Right now we have the baseboard heater in that bathroom on full crank and the door closed. Is that the right move? What if it is a frozen pipe and it's busted, are we setting ourselves up for a flood?

And, of course, if it's not necessarily a frozen pipe, what else could the problem with my shower be?

Any help greatly appreciated!

Keith Weagle - Member

Frozen pipes are very likely if they are on an outside wall, or in this case a garage that is not heated. Have they ever frozen before? It is probably a good idea to shut the water off or at least keep a close eye on the bathroom as if they are indeed frozen and they are copper, it is likely you will have a flood on your hands when they thaw. If they are plastic pipes, it is unlikely they will be damaged from freezing. Is it possible to heat the garage?

rktrump - Thread Starter

A space heater is all I could do for the garage, and I'm not sure how safe that would be unattended. It would also be a losing battle for a poor little space heater in the brutally cold garage.

Hubby went ahead and opened up the wall. Pipes aren't crazy cold in there, but there's a crawl space attached to the garage and under the bathroom where the pipes run. He says the pipes down there are icy cold, but nothing visibly harmed. We have a space heater running under there now.

Again, I'm not really comfortable leaving an unattended space heater running all night, so I suppose I'm hoping the pipes thaw soon, then we leave the shower dripping until temperatures rise a bit?

The pipes are copper, by the way.

rktrump - Thread Starter

Update: the space heater in the crawl space did quick work. The pipes are thawed and running fine - looks like we dodged a bullet.

So, what's the best way to prevent pipes from freezing in the short term (temps will rise in under 48 hours according to the weather forecast)? What about the long term?

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Keith Weagle - Member

Very likely they are frozen in the crawl space, especially if there is any draft at all in the crawl space combined with very cold temps. If once they thawed and there are no leaks, I would definitely put some pipe insulation on them at a minimum and seal up any possible drafts. If you have never had issues with them before, that might be enough to stop it from happening again. You could also get some heater cable and run that under the pipe insulation if you want to be really safe.

If you have a propane torch, and the pipes are not too confined, you could try using that on the pipes to warm them up, just be careful not to use too much heat, especially at any joints, as you run the risk of melting the solder in the joint, and then you have a whole different problem.

Keith Weagle - Member

Great news! Take the steps in my previous post, and also be sure to seal up where the garage drywall was taken down. While it is down you should add some pipe insulation there as well. It is always advisable to leave an access panel so you can get to these pipes if there is a problem, or if you need to change out the faucet. You may want to just put a removable panel over the hole just in case.

drooplug - Member

If you run the the water, they will be unlikely to freeze. Keep at a dribble so you don't waste too much water.

The best way to insulate the pipes is to have the insulation below them and none above them. That way the warm air from the house can get to them.

rktrump - Thread Starter

We've been running the water and have purchased the insulation. Great tip about not covering the top of the pipes!

We'll keep the heater cable in mind as a backup plan and be sure to plug any drafts in the crawl space.

Thanks so much for all your help.

Keith Weagle - Member

I was under the impression that these pipes were under the floor joists in the crawl space, in which case you would want to insulate them completely. If they are in fact against a heated wall or floor, indeed you only want to insulate the cold side and remove the insulation on the warm side.

rktrump - Thread Starter

Hmmmm, hubby reports that they run just under, up against, the joists. So, do we try to get insulation all around them?

Keith Weagle - Member

In my opinion yes. Even if the floor is not insulated, there will not be enough heat from it to help the pipes at that distance. Usually, you would only leave the wall or floor side of the pipe open if it is within an inch or two of the heated surface.

Biggest thing it to stop the drafts. They will freeze a pipe faster than cold stale air.

Also, a note on the insulation, I assume you got the foam pipe insulation? You don't want to use fiberglass for this because it does not block the air from getting to the pipe, and also has a very low R-value when it is compressed.

rktrump - Thread Starter

We got Armaseal, which is rubber pipe insulation. It shouldn't be too drafty down there, but we'll look for any places air may be flowing in, and we'll work on getting the insulation around the whole pipes, which are not that close to the heated area.

Thanks!!!

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