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.

\"Oh, by the way\"

the contractor said when I showed up on the jobsite to check the heating, "the owner decided they wanted cork under the hardwood floor". This turned out to be an after thought; a material between the Warmboard and hardwood to give the floor some spring, but they didn't think to talk to me or the designer before putting it down.

Now I'm worried about it. It looks to be 1/2"; anybody know the R-value?

Best wishes,


<A HREF="http://www.heatinghelp.com/getListed.cfm?id=53&Step=30">To Learn More About This Contractor, Click Here to Visit Their Ad in "Find A Contractor"</A>


  • jfox
    jfox Member Posts: 44
    R value of cork

    Wirsbo design manual lists 1/2" as 0.6 (Appendix E). A lot better than I thought it was going to be.

    Hope this helps.

  • GW
    GW Member Posts: 4,676
    try using a clause like this one

    We have calculated the radiant to perform with __________ R Value floor covering. Any changes may affect our calculations.

    To Learn More About This Contractor, Click Here to Visit Their Ad in "Find A Contractor"
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    [email protected]
  • Dale
    Dale Member Posts: 1,317

    was the first real insulation, many years ago I was working in Fulton street in Chicago, the meat district, all the lockers were refrigerated with ammonia. someone was cutting a door and the wall opening had cork between the rooms that was almost a foot thick! Put in in the late 1800's they told me.
  • Mike T., Swampeast MO
    Mike T., Swampeast MO Member Posts: 6,928
    R-value of cork

    I find various numbers from 3.125 - 3.7 per inch. VERY good insulator. This is for essentially natural cork.

    The only place I find low numbers are from RFH sites when used as the FINISH floor.

    Found even higher numbers for specialty "cork boards" that contain lots of things besides cork--the insulative properties are sometimes ENHANCED in such.

    You may have a BIG problem on your hands. I would definitely find out exactly what they are using and contact the mfgr.
  • Steve Levine
    Steve Levine Member Posts: 106
    contract clauses

    I would suggest that "Any changes would affect" SYSTEM PERFORMANCE. They may say that if your calculations are affected, "so what".

    Steve Levine

This discussion has been closed.