Click here to Find a Contractor in your area.
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/.

Slab insulation....

kcopp
kcopp Member Posts: 3,819
I am looking at a radiant job and working w/ a contractor..... The building owner is insisting that the slab only needs the bubble foil crap for slab insulation under radiant tubing.

Where is it in the 2009 energy code that you must insulate it to r10, aka 2" of blue board?

Comments

  • paul_79
    paul_79 Member Posts: 91
    slab insulation

    back away slowly
  • kcopp
    kcopp Member Posts: 3,819
    ya ya ya...Foam is the way to go...

    But really... where is it? I need the documentation please. And I won't back away. I will run.
  • icesailor
    icesailor Member Posts: 7,265
    It's on the label on the roll:

    Silly boy. It's right there on the label on the roll. And the salesperson told you so. 1/4" of foil faced bubble wrap is equal to 2" of blue foam board.

    I personally again achieved the distinction of A$$hat for telling an airhead that it wasn't so. I was told I was an old fart a$$hat and should get with the modern stuff. They use it all the time so it must be OK.

    It's right there in the code. They just haven't been able to find it again. But it's there.



    BUT, Maybe, just maybe, the 1/4" of bubble wrap is equal to R-10 in REFLECTIVE. Just maybe not in resistance.
  • icesailor
    icesailor Member Posts: 7,265
    Where is it?

    See that blue (or green) plastic house on the job that someone comes by with a suck truck and sucks out the effeluent? There's a white roll of paper on the wall. Its on there.

    It's on one of the sheets near the end.
  • hot_rod
    hot_rod Member Posts: 15,023
    Robert Beans Healthy Heating

    .com website has the best source of info on bubble insulation. And many other well researched topics, not a bunch of hearsay and "spin" over there.





    www.healthyheating.com/Page%2055/Page_55_o_bldg_sys.htm#.UIirFI76pJ0
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • kcopp
    kcopp Member Posts: 3,819
    Been there....

    good info. Where in the IRC does it say you need r5 or r10 insulation under a slab? It certainly makes sense to do it... The right thing to do is use  EPS foam BUT  are you required to do it by "law"/ code.... and if so chapter and verse... I have looked and can't find it.
  • paul_79
    paul_79 Member Posts: 91
    slab insulation

    code or no code, you are responsible to give the customer the best designed and working

    radiant system, part of the system is the insulation under the slab and the edge insulation. if you can't in good conscience put what you feel is the best product or follow the best installation practice then you have to walk. otherwise on the coldest winter spell the complaint will be, " the house is too cold " or " my heating bills are to high. at that point you can't put the insulation under yards and yards of cement. radiant heating isn't rocket science but you have to get the Whole install right, miss one aspect of the system and the whole thing suffers.
  • hot_rod
    hot_rod Member Posts: 15,023
    State by State?

    Here is a link to the Washington State code, regarding slab insulation



    .

    www.energy.wsu.edu/Documents/BFG%20Chapter%202-Jan2011.pdf
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Zman
    Zman Member Posts: 6,981
    2006 IRC

    I am looking at the 2006 IRC. Table N1102.1 on page 319 shows r-10 for zones 4-8

    Hope that helps.

    Carl
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • NH03865
    NH03865 Member Posts: 38
    2009 International Energy Code

    The requirement is in the 2009 International Energy Code Table 402.1.1

    It is based on your climate zone.

    It does not require under the entire slab, just at the edges.  Note d. adds an R5 requirement if the floor is to be heated.

    I have attached the page from the standard
  • kcopp
    kcopp Member Posts: 3,819
    Thank you...

    very much!
This discussion has been closed.