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JACKNASTY Member Posts: 3
I have an L shaped master bath (high ceiling), coldest room in the house.  I have 2 registers one by vanity and one by toilet.  Seems to be blowing great but room is at least 10 degrees colder than the rest of house. I have a whirlpool tub kitty corner with double casement windows. I believe these are the cause of the major heat loss because, no supply in the area because of whirlpool deck/build. Can anyone recommend anything to alleviate issue??  New/additional register placement location? Any help would be greatly appreciated....Have a great day!

             Mr. Nasty


  • kcopp
    kcopp Member Posts: 4,390
    You best bet....

    Find a way to get in behind the tub and seal up the outside wall... spray foam insulation is a good candidate. You can throw in a ton of heat but is is all for not if it heads out through the walls. The other advantage is you do this one time and it always pays you back.....more heat will cost you every heating season.
  • Paul48
    Paul48 Member Posts: 4,469

    Make sure it is closed-cell foam. It will not absorb water. Foams like Icynene are open-cell and are like a sponge.
  • Techman
    Techman Member Posts: 2,144

    How many outside walls does the room have? What is under the bathroom? What size duct and how long of a duct run to each of the two supplies? What are the room diementions? Is the bathroom door open or closed when not in use?
  • RobG
    RobG Member Posts: 1,850
    Bathroom heat

    I agree with Kevin. When a home is built, the insulation is the last thing to go in before drywall. That said, the soaking tub on the exterior wall was put in prior to to the insulation. I have seen on many occasions the exterior wall behind the tub not get insulated. Hopefully you have an access panel, have a look and insulate if needed. Good luck, Rob
  • SWEI
    SWEI Member Posts: 7,356
    insulating tubs

    A friend who has been wet-spraying cellulose for 20+ years likes to fill the entire void under bathtubs.  Silences the tub and holds heat like crazy.
  • icesailor
    icesailor Member Posts: 7,265

    By mentioning "registers", I assume that the bath is heated with warm air heat and not fan coils. It is my experience that most modern scorched air systems suffer from emphysema, They let out vast quantities of warm or cold air but have little to no return air.

    Back in the Pleistocene age, all scorched air systems had a supply and a return in each and every room. To get costs down, someone decided that you only need one common return in the house and that all the air will return there. As long as the doors are open. If you have such a system, you need to be sure that a good chunk is cut off the bottom of the doors. If the system is running, and you almost close the door and it then slams shut, you have a breathing problem.

    If you have soffit vents to ventilate the above space, and the bath side faces the NW or prevailing cold winds in winter, the attic space could turn the ceiling into a cold sink plate. Especially if you have any recessed ceiling lights. Even the ones that are supposed to be air tight. The fourth great lie.They won't leak air.
  • Gordy
    Gordy Member Posts: 9,546
    Lack of bath heat

    To the OP, if you are getting good air flow to the heating ducts I doubt lack of return registers is a problem. There should be no returns in kitchens, and baths anyway.

    You're probably suffering from lack of insulation around the whirlpool. And the large casements in that area are probably allowing the bathroom to cool, or not reach thermostat setting when the rest of the house does.

    Could also be that the duct supply to the bath is suffering some severe heat loss. Could this be a long supply run to the bath?

    By this I mean that the rest of the house is satisfied on a heat call, except for the bath in question. Is this true? Do all other rooms in the house reach set point except for the bath in question, or is there other rooms that suffer lower set point temps on a call for heat.
  • icesailor
    icesailor Member Posts: 7,265
    Returning home:

    While that may be true that you don't put returns in baths and kitchens, you need them close by. I agree with you 100% that the heat loss may be greater than the heat input. But, if the door into the bathroom is too close to the floor, there is no way for the air to circulate into the conditioned space at the flow rates that the designer used. You need to measure the temperature of the outlet air.

    To prove and agree with your point, I've been to a few freeze-ups where the outlet air was perfect for summer AC and this was January. But in July, the outlet was just hot enough to be perfect for January.
  • Gordy
    Gordy Member Posts: 9,546

    Totally agree with you ice. Doors need be under cut even for bath exhaust fans which doubles return starvation on a heat call. Was hoping to extract more info from OP.
  • icesailor
    icesailor Member Posts: 7,265
    Bath fans:

    Interesting you bring up bath fans. I never consider them because I personally, never turn mine on because it sucks so much heat out of a room. But it is a major consideration.

    I really haven't seen many or any rooms like bathrooms that were truly under heated. They all had excessive heat loss from building practices that couldn't be computed into the heat loss calculations.
  • ScottWarmly
    ScottWarmly Member Posts: 3
    Another train of thought

    Hello Mr. Nasty. Have you thought about Electric radiant heating under tile? Or, if the floor is already done, electric radiant panels like a LAVA radiant panel? These are very good for providing extra heat in a room like this.
    Just so you know, I work for WarmlyYours.
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