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.

Hydro Radiant Heating with 4" concrete slab on top of Insuldeck

jamesanderson
jamesanderson Member Posts: 5
in Radiant Heating
Do you think this layout is the best way to install the pex on my 4" concrete slab on top of Insuldeck? Going through the forum i see various ways, so wanted to get some opinions. I have quite a lot of windows and the house is ICF.

Comments

  • hot_rod
    hot_rod Member Posts: 23,416


    it seems like long leader lengths to get from the manifolds by the garage to the great room. Could the great room loops go to the manifold by the bathrooms to avoid the long runs? It seems like that entry hall from the garage will maybe over-heat with all the tube packed in there?

    Where is the mechanical room, how do you get supply and return to the 3 manifold locations?

    Who did the loop layout and design?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • jamesanderson
    jamesanderson Member Posts: 5
    The mech rm is in the basement which is about 17ft below from the first fl. through a crawl space. Thinking of insulating the pipe going up from mech rm.
    Radiantec designed it. I read that the loop should start, or hottest water should be on the perimeter near the windows but it is not here.
    Should one of the manifold be moved to 1/2 bath to be closer to the great rm is that what you meant? The one supports the garage stays next to the garage inside the laundry rm?
    The great room has 20ft ceiling open up to the 2nd floor which has wood truss 19" center and will have the same radiant heating. For that they just said that to put pipes under the floor with some metal panels and insulate. Any advise there?

  • hot_rod
    hot_rod Member Posts: 23,416
    I’d sure like to see the heat load calculation for that great room. The tubing layout doesn’t always assure that the room can be covered by just radiant.

    Yes, move the great room manifold out of the garage area closer to the room itself. It seems the great room should have its manifold near the bathroom manifold?

    Is that a large glass expanse near the piano? That is where I would run the tube the opposite way pack in some 6” on center runs.

    I’m not clear how you use plates under the InsulDeck? If this is the product you are talking about?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • jamesanderson
    jamesanderson Member Posts: 5
    Yes, that is what i have for insuldeck, 9" EPS foam and then the pex will be tied to the rebars on top and then pour 4" concrete. The thin plates it is for the 2nd floor wood truss not the 1st fl insuldeck area.

    Yes, all my windows are quite large, aluminum triple glass, next to the piano is going to be 21.5ftx 16.2ft high. I should start the run for this area coming out of the 1/2 bath then go straight to the window area and then run 6" apart and back to the manifold.

    You mentioned about the hallway area with 6 lines running i think will get too hot, what should be the minimum lines? ( the shaded area is staircase open to below basement)
  • hot_rod
    hot_rod Member Posts: 23,416
    edited January 13
    I'm not sure where they come up with the "energy factor" for the room heat loads?
    They also indicate 65° temperature differential. So on a zero degree day, the home is at 65°? Is that warm enough?
    Does it drop below 0° in your area? If so the indoor temperatures falls below 65°?

    The design should be based on the lowest temperature your area experiences. Called a design day.

    Is this a system you are installing yourself?
    If you hire a hydronics company, let them do a load calc that they are comfortable with.

    I believe you can send your plans to Rehau, Uponor, Watts Radiant for a design. If you want a second opinion. Many plumbing wholesalers do design as well as manufacturers reps. Buy their product if you use them for free designs :)

    Or if you like crunching numbers you can do a manual load calc, at least for that great room. The 348 sq feet of glass at one end sends caution signals up.

    The main zone at 1442 square feet X 25 btu/ sq ft (realistic output from a comfortable floor at 82°)
    from the floor= 35,550 btu available, they show 56,880 btu/hr?

    The Uponor design guide has a step by step manual calc form. It takes into account the actual dimensions of walls, ceiling, doors and windows. Example below, for a simple one room.

    Also the address for the free Uponor design guide. Or just google Uponor Design CDAM

    Bottom line, get a second opinion on that load calc and design.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • dko
    dko Member Posts: 668
    Agree, please note the note with their freesistance.



    And they don't put their name on the loopcad, so they don't own it. None of it is particularly accurate and like they say, should only be used as a preliminary measure.
    kcopp
  • jamesanderson
    jamesanderson Member Posts: 5
    65 deg is cold, it should be at least 72deg, it is E. TN area. This tue it is going to be 9 F due to arctic blast. I have a plumber who said he has never done it but will install if i give him the materials and design. I have reached out to several in my area but no luck. I bought materials from Radiantec and that was the design they gave but seems they did not take a lot into considerations and i am stuck with them. I will download the CDAM and do calc. and try to get a second opinion.
  • jamesanderson
    jamesanderson Member Posts: 5
    I have the loopcad 2023 software and have redesigned the loops and have added other info keeping the same number of manifold/circuits. Found out that 65deg is ideal for radiant in calc. Now i have the software if anyone needs help in designing let me know since this forum has been helpful for me.

Categories