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  1. trailblaze

    trailblaze New Member

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    South West PA
    i just got this email from the manufacturs of wonderboard...

    "½” Wonder is non-combustible and it has an “R” value of 0.134 @ 75 degrees"


    well i guess this throws my plans out the window...i'd need 2.5 inches of this stuff to make it slightly work...

    however, the r value is at 75 degrees.... what about the temp under a stove.. would that R value raise or lower??

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  2. begreen

    begreen Mooderator Staff Member

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    That doesn't jibe with what I've read, I wonder where they got that figure for that board.

    Use Durock brand (by USG) instead. A 1" thickness will give you R .52, 1.5" = R .78.
  3. trailblaze

    trailblaze New Member

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    i can't find any places around to purchase Durock.

    maybe it's the temp factor? maybe at like 150 degrees it's .268 per 1/2 which puts it at approx .52 at 1 inch??
  4. begreen

    begreen Mooderator Staff Member

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    Do you have a Home Depot or Lowes nearby? Durock is pretty common.
  5. trailblaze

    trailblaze New Member

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    Loc:
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    i have multiples of both stores... they looked at me like i was nuts when i asked for Durock Cement board...although most of those workers don't know their left foot front their right...



    i just got an email back from wonderboard... they say the R value will decrease with higher temps...
  6. begreen

    begreen Mooderator Staff Member

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    It sounds like they gave you the R value for a 1/4" thickness and not the 1/2" sheet. As long as you get the 1/2" cement board (not the lightweight Wonderboard or Durock) I think the R values are identical. Ask them why Durock is twice the R value for essentially the same product.
  7. fossil

    fossil Accidental Moderator Staff Member

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  8. trailblaze

    trailblaze New Member

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    Loc:
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    i agree... something doesn't sound right about an R.134

    i swear, dealing with people anymore is a pain in the butt..i am sooo frustrated right now

    BeGreen.... i called the local Lowes... demanded i speak with the store manager, who personaly looked for the Durock brand and what would you know... THEY CARRY IT...

    if i could have got this response the first time it would have saved me a lot of trouble...

    i'm putting 3 layers of Durock down and being done with it...
  9. fossil

    fossil Accidental Moderator Staff Member

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    Hey...we're people. %-P Rick
  10. trailblaze

    trailblaze New Member

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    not you guys... the people at lowes
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