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.

Radiant layout and sizing program

Hello everyone I am a plumbing and heating contractor in northern New Jersey.  Recently I've been getting more requests for radiant heating. I do alot of steam and baseboard heating. Also put in combi and high efficiency boilers. I understand radiant but haven't had to install the tubing. Can anyone recommend a program that they prefer to use for sizing and layout of circuits? Its doesn't have to be a free program as I am willing to pay for one if it's better. Thank you for any suggestions!


  • STEVEusaPA
    STEVEusaPA Member Posts: 6,505
    Rehau has a program you can try for free, but it's a little complicated and you may get easily frustrated.
    Wrightsoft has the best software, but when you add up all the modules, it gets a little pricey.
    John Siegenthaler sells a program that works pretty well, not as expensive.

    But your best bet may be to find a supply house that uses wrightsoft and has a person who does design work. Give them the plans, let them design it, buy all the tubing, manifolds and components from them. You'll get a full report, component call out, loop lengths, flow rates, near boiler diagram and on and on.
    The one I use even lends you a tubing uncoiler, and a tubing stapler.

    There was an error rendering this rich post.

  • Derheatmeister
    Derheatmeister Member Posts: 1,550
    We use Viega's LoopCad..
  • psb75
    psb75 Member Posts: 845
    One word: Uponor
  • WillC
    WillC Member Posts: 23
    Try LoopCAD 1 month unlimited free use
  • GroundUp
    GroundUp Member Posts: 1,926
    Once you understand how radiant heat transfer works, any of the layout programs are subpar at best IMO. They fit the tubing to the space, but the vast majority of the time the layout can be improved upon. I feel Uponor's program is best overall, but like the others still doesn't often lay out the tubing in a proper manner. Hypothetical scenario: say you have a 20x50 slab with the manifold location in a corner- in most cases the software will run the first loop down 70 feet of exterior wall and back a couple times. Obviously the exterior wall is always the coldest part of any slab, so 70 feet into its 250ft trip, the fluid has already given up its usable heat and the remaining 180ft is just along for the ride instead of actually emitting heat. Meanwhile the 2nd loop is actually backfeeding heat into that 1st loop from the center, so it appears to be well balanced at the return manifold despite the wildly varied slab temp. Personally, I design my own layouts to balance exterior wall exposure evenly between loops whenever possible and maximize system efficiency. No program I'm aware of will do that on purpose.
    delta TSTEVEusaPAeaucielRich_49
  • HomerJSmith
    HomerJSmith Member Posts: 2,468
    I would go to Uponor and Rehau, etc, web sites an download their design manuals
  • eauciel
    eauciel Member Posts: 5
    What are your thoughts on heating rooms according to function using hydronic radiant heat? I avoided thermostats on loops by designing the layout of the house so that warmer rooms, bathroom and walk-in shower, were on different loops than cooler rooms, like bedrooms. I then adjusted the amount of tubing per sq foot as a percentage of temperature difference from standard living area temperature. After 8 years it’s still working out.  
  • tocker
    tocker Member Posts: 30
    What is best for designing a panel radiator system?
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,505
    tocker said:

    What is best for designing a panel radiator system?

    Same as other methods. Determine the btu requirements for the room, at a desired water temperature, match that to the output of the panel radiator. The panel radiator manufacturer will have that data.

    There was an error rendering this rich post.

  • EzzyT
    EzzyT Member Posts: 1,296
    Just a suggestion on the panel rad system use trvs  h patter valves with bypass and use a odr control to trigger constant circulation 
    E-Travis Mechanical LLC
  • bill_brooks
    bill_brooks Member Posts: 50
    when i was designing my new house, i was still thinking in 180deg. terms. i had never done a radiant design before. very bad for my desired radiant heating scheme.
    one day i was visiting my cabinet supplier who was also supplying my plumbing fixtures. he said.........
    i have a rehau program that can size and design your house. if you haven't spec'd your boiler yet,
    i can throw that in as well. well....step right up!
    not only did he supply a computer-driven (mine was a hand-job) heating layout, but a boiler as well!!

    hosanna! i had to spec. virtually nothing. he even had a radiant jobber who i could work with! (too easy)
    all i had to do was spec. and provide the heating transfer subtrate ( a co. from colo.who did the install)
    suddenly, i was sleeping 8hr. nites! the whole process except the lw heat crete, was now in the schedule!
    the crete was really quite similar to concrete except lighter.

    within less than a month, everything was installed and commissioned. what a pleasant experience.

    to date, my only problems have been replacing the Quietside 9x boiler twice. none of us could have
    forseen them leaving town about 5yrs. after commissioning. no spare parts. such is life.

    i bought a new weil-mcclain boiler after the quietside pooped, and have never looked back. it's a very
    quiet and versatile boiler. cudos to weil-mcclain!

    while i usually prefer multiple suppliers for specialties, i obviously had the gods smiling on me!