How does an R22 Wall perform as an R50 Wall?
Both the attached documents are produced in consultations with the PCA and CTL Engineering in Skokie, Illinois. One is the report which ‘theorizes’ using computer modeling in accordance with ASHRAE 90.1 that a 10′ thick minimum ICF wall (Ours has got this beat by 1 ΒΌ’ thickness) will in many cases perform equivalent to a Stick or Frame Built wall insulated to a value of R50. Study the report tables closely – you’ll see this is true for more southerly US regions only – as you come farther north the number goes steadily downward and if we in Canada lived and died by the claims of this report – we would have all stopped selling ICFs years ago, as it suggests we can only credit the ICF for thermal performance of R22 (it’s calculated R Value) only slightly better than a frame wall. What this report does NOT take into consideration is the Air Tightness of the building – which Peiter van der Verf”s “ICF Comparison to Wood Frame” does. The crux of his report is that it was based on actual stat
