My wall construction is 2×4 filled with cellulose and 4-1/2″ urethane screwed to the outside.
user-1141733
| Posted in Energy Efficiency and Durability on
My wall construction is 2×4 filled with cellulose and 4-1/2″ urethane screwed to the outside. Is there an advantage to put a 1″ air space between the 2 insulations? If so how much does it improve the R value?
Thee wall has an R-45 without the space.
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Replies
Q. "Is there an advantage to put a 1" air space between the 2 insulations?"
A. No. An air space increases the chance of heat-robbing infiltration and exfiltration, as well as heat-robbing convection loops.