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Spray foam over pipes?

grye Member Posts: 88
Hi all,

Almost all of my plumbing runs from my utility room, through the garage and up into my home. Last year we had our pipes freeze but luckily caught it in time before anything bursts. Directly above my garage is my kitchen which is always cold and the floor freezing.

So my question is can I pull down the Sheetrock and spray spray foam over the pipes? There's nothing there now.

Had a small leak so I cut open the Sheetrock to take a look and saw there was absolutely nothing there. I could see light shining down from every place a pipe went through the first floor.


  • STEVEusaPA
    STEVEusaPA Member Posts: 6,505
    I wouldn't. If you ever get a leak, you'll never find it in that mess. And replacing pipe would be impossibly difficult/messing. Can't you just wrap the pipes with the proper sized fiberglass and insulate the ceiling.
    You could spray foam the penetrations.

    There was an error rendering this rich post.

  • Jamie Hall
    Jamie Hall Member Posts: 23,675
    Insulating the ceiling is going to be the first step -- and make sure that all the pipes are above the insulation. That may help, but if the garage gets well below freezing...

    You might even find you needed to heat trace the pipes.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • ChrisJ
    ChrisJ Member Posts: 15,929
    Insulate the pipes from the cold, never from the heat.

    I personally, wouldn't wrap the pipes either because then once again you're insulating them from the heat (the kitchen floor).

    It's not my area of expertise, but how about covering the garage ceiling with 1-2 inches of styrfoam panels and then covering with drywall?

    It'll lower the ceiling which could be bad depending on the height, but it'd make the kitchen floor and pipes warmer.

    Just giving ideas.

    Another option is you could heat the garage, maybe? :)
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • jbo
    jbo Member Posts: 12
    Just think about heat wanting to move to cold. Hot air rises but heat doesn't. If your garage isn't heated and there is nothing stopping the heat from going there, it will. I agree that spray foam sounds like a mess to deal with for access to the pipes and that if the pipes are running right below the kitchen floor you may not want to block the floor from the pipes as you can get some transfer into the floor (likely small but hey if the floors that cold any bit helps).
  • 2x_Tom
    2x_Tom Member Posts: 12
    edited April 2017
    Any chance of rerouteing them through a warm space?
    Another option. You could add a recirc line on the hot. Insulate against the cold and don't wrap the pipes in the areas prone to freezing. Your hot lines won't freeze and should provide enough heat to keep the nearby cold line from freezing. You could use the same strategy with the heat lines in the area. Bunch everything together but not so much that it severely affects your water temps.
  • Gordy
    Gordy Member Posts: 9,546
    edited April 2017
    Unconditioned garages under living space is never a good idea, but sometimes unavoidable. Deffinetly do not spray foam for future failure reasons, and flame spread.

    No matter how much you insulate the floor will be cold. Especially if it is a forced air heating system in the home.

    As mentioned insulate below the pipes so any residual heat from the conditioned space can help keep the pipes above freezing. Recommend Roxul insulation. Make everything snug fitting, and spray foam were pipe penetrations come through the floor.

    I would not recommend foam insulation in a ceiling for a garage space even if properly covered with class x gypsum. If there is ever a garage fire the ceiling will be getting the intense heat, and flames more so than a cold partition wall dividing a garage from the living space.

    The best option which may not be the cheapest, but would give the best results is to condition the garage even if it's only kept 40 degrees.