Steel roof insulation question

Discussion in 'Shop Talk' started by Old Jack, Jul 13, 2004.

  1. Old Jack

    Old Jack Truth Seeker

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    I have steel roofs on the house and upper cellar house. what is the best way to insulate these?
    Does any special consideration need to be taken for condensation?

    Air flow?
    They both have ridge venting and venting at the eaves.
     
  2. Ross

    Ross Moderator Staff Member Supporter

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    Are they fastened on strapping or directly to the subsurface? You're supposed to leave an air gap with strapping but I have both and don't notice an appreciable difference. As long as the steel can cool moisture won't be a big problem, so power venting the atic might be a requirement. The attic space in my house is 6 inches of fibreglass and 8 of blown insulation. Its been fine every time I have checked and the steel on my roof is screwded directly to the plywood subsurface.
     

  3. Old Jack

    Old Jack Truth Seeker

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    ---------------
    There is no subsurface, the steel is mounted directly to the roof beams, which are rough sawn hardwood 2x6's (real 2x6's). Venting the attic makes sense, I have to run power through there anyway. There's a guy here who advertises in the Green Tab ( a local recycler/penny saver type rag) a blown on foam treatment for steel roofs. Have you heard anything about this?
    I'm imagining it's something like "Great stuff" but on a larger scale.
     
  4. joan from zone six

    joan from zone six Well-Known Member

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    the sprayed urethane foam you mention is great stuff - no condensation, fantastic r-value, awesome adhesive qualitiers - downers - expensive, noxious fumes if burned, difficult to replace roof sheathing