Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Connecting radiant to baseboard heaters?

I have a 80 Sq ft mudroom that I want to add radiant heating to. The rest of my house has hydronic baseboard heaters. Is it possible to simply pipe the pex tubing directly into my 1st floor heating loop?


  • Jamie Hall
    Jamie Hall Member Posts: 22,892
    Sort of. You will need a mixing valve, though, to bring the temperature of the water in the floor down. There could be some interesting plumbing involved...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Ironman
    Ironman Member Posts: 7,341
    Uh...probably not.
    Not only will you have to mix the water temp down as Jamie mentioned, but there are other considerations:

    The mud room will probably heat up or cool down quicker than the rest of the house. That would mean it needs its own zone, thermostat, etc.

    Then there's the problem of adding increased head (flow resistance) to the baseboard loop. If the BBs are series looped, then putting 120+ feet of 1/2" pipe in series with 3/4" BBs will result in flow being seriously restricted and any BBs down stream would be starved for flow and heat.

    A mixing valve would also necessitate another circulator.

    If make the the floor a separate zone, then you would short cycle the boiler to death because of the micro load created when only that zone calls.

    If it's a typical mud room with a lot of exposure and glass, the floor may not be able to emitt enough heat for the room in cold weather.

    You may want to consider and alternative source such as an electric radiant grid with BBs added to the mud room. The floor grid could pick up the slack for the BBs when needed and be controlled separately.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.