Insulation “R Value” Testing Comparison

May 5, 2011Leave a reply

Insulation Material Test – ASTM C518
* Standard test for rating most insulation products
* Test uses guarded hot plate apparatus – tests insulation material sample
* Testing usually conducted at room temperature over a few hours
* Test does not consider factors such as air movement, thermal bridging, etc.

Insulation Material Test – ASTM C518
1″ P2000 = R-4.11
6″ Fiberglass = R-19

Installed Insulation Performance Test – ASTM C1363
* Test measures insulation material in installed state (as part of wall section)
* Installed testing considers factors such as thermal bridging, surface convection effects and installation deficiencies.
* While still a laboratory test, measures more real-life conditions than ASTM C518
* Replaced standard guarded hot box ASTM C236
* Measures temperature difference interior / exterior

Installed Insulation Performance Test – ASTM C1363
1″ P2000 in 2″ x 6″ frame wall = R-10.2
6″ Fiberglass in 2″ x 6″ frame wall = R-11.5

CONCLUSIONS:
1. Installed Performance tests are more relevant to real life performance.
2. Installed Insulation Performance testing showed that 1″ of P2000 Insulation performed about the same as 6″ of fiberglass insulation
3. Discrepency between fiberglass test results (material test versus installed test) confirmed by several independent studies.

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