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Harvey RamerHarvey Ramer Member Posts: 2,214
Why do people put dw plumbing in outside walls? Frozen pipes, frozen pipes, frozen pipes!!!! It's sunday morning, cold as the blazes and I have to go fix frozen pipes. arghh....
Ramer Mechanical
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  • GordyGordy Member Posts: 9,523
    edited February 2015
    Dress warm Harvey.
  • j a_2j a_2 Member Posts: 1,796
    Hi I can’t imagine a true lic. plumber ever ever doing that…I used to carry a comercial heat gun with a flexible wet vac hose…Had to put a small hole in lower wall but I had great success….and never once a fire….Hope the installer is enjoying his vac. in Florida on the h/o dime…Whoops unless it was Mr. homeowner…In these parts the ins. companies will not pay for shoddy work by non lic. and insured companies….They check town/city hall building permits…The damage from burst pipes can all but ruin ones home...
  • FranklinDFranklinD Member Posts: 399
    Up here, the homes built prior to 1960 or so all have all the water and waste lines run through the 'middle' of the house, kind of like a 'utility core' in a larger building. My 1914 home, with very little insulation, has never had frozen pipes, and neither had my moms 1890-something house.

    The runouts to all the second floor rads are all on outside walls, but not IN the walls...all are within the heated space of the first floor.

    I know I've seen some 80's remodels around here where kitchens and bathrooms were done with plumbing on outside walls. Even with good insulation and all that, 10-11 days well below zero with 20-30 mph winds can drop the temp in a kitchen cabinet to surprising lows. Not shocking to walk into some of those houses to find kitchen cabinets all wide open...
    Ford Master Technician, "Tinkerer of Terror"
    Police & Fire Equipment Lead Mechanic, NW WI
    Lover of Old Homes & Gravity Hot Water Systems
  • icesailoricesailor Member Posts: 7,265
    Waste pipes in outside walls only freeze if people don't pay attention to leaking bye toilet tanks. The slowly running water starts to freeze.

    As far as water and heat pipes, if you put them to the front, closest to the heated space, with no way for Itchy Richie to run the insulation in FRONT of the pipe (so it is on the cold side of the insulation) it won't freeze. No matter what or how much time it took, I always went back to check insulation after the final rough inspections to check where the Hackaroo's could ruin my life. The heat from the room is always passing in to the pipes first. The cold has to travel all the way through the insulation. You've got to be on your toes. Especially with pipes around Rim Joists.

    With the cost of cheap "Point & Shoot" digital cameras, one is wise to photograph everything you do. Especially stuff buried in a wall. Cheap insurance against the Hacksters.
  • Harvey RamerHarvey Ramer Member Posts: 2,214
    2 down, anyone else while i'm at it. First guy was lucky. I caught it and got the pipes thawed before the copper burst. Excess infiltration was the cause.

    Second guy wasn't so lucky. He will be gutting 2 bathrooms. 1/2" soft copper running through exterior wall with the insulation on the house side. Wooden clapboard siding. The pipes were basically outside for all intents and purpose.


    Fortunately all work was inside Gordy.

    Uhohh, here come the heat pump calls. House set to 70 and it's only 63 inside. My Sunday is shot.
    Ramer Mechanical
    To learn more about this professional, click here to visit their ad in Find A Contractor.
  • icesailoricesailor Member Posts: 7,265
    In a 2 X 4 wall and a 2 X 4 on the flat, with Van Hangers, moves the hole 2 3/4+ Center of the hole. 3/4" in from the front face of the stud wall. There is no way to put insulation in front of the pipes without a huge bow in the sheetrock. It HAS to be installed behind the pipes against the wall. In a 2 X 6 framed wall, with a 2 X 4 on edge with a Van Hanger, it is 4 3/4" from the back to the center if the hole. Ouch plates top and bottom. The good ones. Not the thin ones that you can run metal stud drywall screws through easily.
  • Jean-David BeyerJean-David Beyer Member Posts: 2,663
    When my contractor remodelled my kitchen, there were lotsa problems. My kitchen sink faces a window. Hence the water and drain is in an outside wall. That wall was all foamed in place before remodelling was done, so they basically gutted the entire wall, put the pipes in, and added some fiberglass insulation batts. I caught them putting the fiberglass on the house side of the pipes, and made them move it. Similarly, a 1/4 inch tube for a possible icemaker in a refrigerator that is on an outside wall also. I got them to put the insulation on the outside of the wall.

    I did miss one, I guess, because the hot water to my kitchen sink froze up a year or two ago. It had gone down to 2.8F that night. Since it is predicted to go down to 0.8F tonight, I will leave the cabinet doors under the sink open, and put a heating pad on that pipe. Unfortunately not where it most needs it. And hope for the best. House is built with 2x4s. Sigh. The original builder did a lot of things right, but some other things were very bad.

    Why do they put pipes in outside walls? Because the house is built on a concrete slab at grade, and the sink was somewhere else when they built the house (facing a blank wall). There were already hot and cold water pipes in the wall for the washing machine, so the contractor thought it would be OK. He thought wrong.
  • Mark NMark N Member Posts: 1,087
    My kitchen used to have a small steam rad in the cabinet under the sink. Can't have frozen pipes with that setup.
  • icesailoricesailor Member Posts: 7,265
    When cold. always open the sink cabinets. Heat flows to cold. If you have bathroom sink cabinets on second floors that back up to unconditioned knee walls, leave the doors open when it is cold. Heat flows to the cold.

    You can put a lamp in the cabinet. Heat flows to cold.

    When you close the cabinet doors, you are adding insulating resistance to the heat in the room from getting in the cabinet.

    Heat flows to cold.

    Anything that you can do to let the heat flow to the cold will prevent freezing.

    In freezing weather, if you turn on a faucet and put your hand under the flowing water, it the water turns colder and so cold that it hurts, cold air was blowing on a pipe and it was going to freeze. If it hadn't already. If the water stops and it is just barely dripping, and I mean barely dripping. leave it on and let it drip. If it finally stops dripping, your toast. If the drip slowly increases, like 3 drips per minute, and after 5 minutes, it goes to 4 drips per minute, it will soon flow.

    In My Experience.
  • WeezboWeezbo Member Posts: 6,232
    edited March 2015
    Well , we have a rule , no plumbing in outside walls. however, if it is within the vapor barrier it is within the building envelope so, with 2by's on the flat over the R-38 walls vapor barrier it is considered within the building. if for some reason your drainage is in an outside wall here , it likely was not installed by someone with a licence nor was it inspected by a state or city inspector.
    I have had pretty good luck with a grunfoss lash up for on demand hot water using some small gizmo that looks like an extruded pls trv that fits inline from the angle stops or straight stops then to the risers of the hot and cold. It consists of a circ , and one of these fancy trv deals , i considered buying a couple ten or so of the fittings they let some water migrate from the hot to the cold and as what goes into a T must leave a T the water in the cold line rolls back to the water heater .while not being a fancy 12 step Lawyer i cannot say do this and everything will be fine ,however , if pipes are not frozen and can be thawed , it might work out to keep the water moving without losing the water down the drain on colder days ...
    *~//: )
    P.S. Venting is allowed . it is sealed where it penetrates the envelope with red tape to the vapor barrier . typically , it is given either a street 45 Xa riser pup by 45 another short pup X 90 to a long sweep 90 up and increased to 3 ' and out or pulled back to the other house venting to keep roof penetrations to a minimum. our vent pipes above the insulation are insulated by code the last 8 or 10 years.
  • j a_2j a_2 Member Posts: 1,796
    In Mass that would be considered a cross connection. Not allowed...just an fyi
  • FranklinDFranklinD Member Posts: 399
    In my house, someone did an 80's reno and moved the kitchen sink from an inside wall to an outside wall under a 4x5 picture window (OLD window). Fortunately they were smart enough to put the supply's, drain, and loop vent straight down through the cabinet floor into the basement.

    I can honestly say, all of the houses I've lived in around here (-20 and high winds regularly from Dec to March) have never had a frozen or burst pipe. Only one common factor between all of them: all were built pre 1930.
    Ford Master Technician, "Tinkerer of Terror"
    Police & Fire Equipment Lead Mechanic, NW WI
    Lover of Old Homes & Gravity Hot Water Systems
  • WeezboWeezbo Member Posts: 6,232
    j a , cross connection ?
    a mixing devise?
    so how do they manage to comply with anti scald?
    which does essential the same thing ?
    are you required to put a check on the cold to the anti scald ?
    is there somewhere the approved recirculation requirements are written so i can follow this logic?
  • jumperjumper Member Posts: 1,450
    Put burlap on the wrong side.Hang a big picture where the pipe is.Then go south for the winter with thermostat way low.Maybe someday you'll burst a pipe.After he repairs the pipe the plumber will put burlap on the correct side and then that pipe won't burst.
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