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Radiant for slab on grade

Pipes79 Member Posts: 2
Hello, I am a plumber, who has installed a few radiant floors 18 years ago in my residential days, I have not been involved in any installations since then. I have been in commercial industrial for the last 15 years. I am in the process of selecting house plan for our house that I intend to build. I would like to build a slab on grade, with radiant floor. I am wondering where I should be looking for good design ideas. Also I would like to install a combination boiler to provide my DHW. Or would I be better to install an indirect storage tank? Any suggestions would be appreciated!


  • Rich_49
    Rich_49 Member Posts: 2,766
    Where are you located Pipes ? What type of envelope construction are you planning on , typical construction or will it exceed code minimum ?
    This is the place where you will get the BEST DESIGN IDEAS .

    To start off with dependent on where you are and what loads you will have , forget the combi unless you plan on one with some mass .
    You didn't get what you didn't pay for and it will never be what you thought it would .
    Langans Plumbing & Heating LLC
    Serving most of New Jersey, Eastern Pa .
    Consultation, Design & Installation anywhere
    Rich McGrath 732-581-3833
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    Rich said:

    forget the combi unless you plan on one with some mass .

    Second that!

    A generous sized indirect is also great in the summer with an add on Heat Pump Water Heater (HPWH) for some cooling and dehumidification in the summer months, if your location requires cooling.


    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • Pipes79
    Pipes79 Member Posts: 2
    Rich/SFM- Thanks! I am building in Eastern Ontario Canada. House will be constructed with 2x6 framing, with a mix of stone/wood on the exterior. I will look into the HPWH. I will require cooling in the summer months. I had planned on installing an AHU with coil for AC. I should have mentioned that I plan on installing a zero clearance fireplace as I have 200 acres of bush to get wood from. I had considered installing an OWB, but have done some research, and not sure if I want to be a slave to it!! Also I had read in some other posts about insulation under the radiant should be 4" thick. Is it worth the extra investment?
    As I get closer to finalizing house plans I will have more info/questions.
  • Hilly
    Hilly Member Posts: 427
    Not sure about Ontario but CSA states 1" foam under slab. Honestly I think you would wise to install 2"Min for R.10