Non-combustible rigid or semi-rigid board insulation based upon 'spun molten rock fiber' and proprietary binders such as those manufactured by USG, Thermafiber or Roxul Co., CavityRock, faced or unfaced, are also worth reviewing for exterior insulation in traditional exterior cavity walls and in ventilated cavity walls. Rock fiber insulation is inert, recyclable, can be made using post industrial feed stock, is permanently resistant to vermin, mold, sunlight, liquid water and moisture. This type of material has been in common use for these ventilated, open joint, exterior wall and for roof assemblies in Canada, the UK and Europe for decades. -------------------------------------------
Joseph Bridy AIA
Bohlin Cywinski Jackson
Philadelphia PA
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