Martin, How about this option?
Tennesseebob
| Posted in Energy Efficiency and Durability on
Thank you for the advice. What about just using it [double-bubble foil] at the ceiling level as this will give me an opportunity to better air seal the cathedral ceiling? Furring out the ceiling will give me an air space that should help radiate heat back into the envelope. Otherwise I will have a hard time air sealing from above, along with the fact that there’s a full width porch across the front that needs to be vented out the ridge.
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Replies
[This question appears to be a continuation of a previous thread: "I have access to some inexpensive double-bubble foil insulation."]
Bob,
Bubble wrap is a poor material for air sealing. If you want to air seal your ceiling, the best air barrier is gypsum drywall. Pay attention to sealing the penetrations and the intersection of the ceiling and the wall, and you'll be fine.
If you want to improve the R-value of your ceiling assembly and interrupt thermal bridging through the framing, I suggest that you use rigid foam (for example, polyisocyanurate), not bubble wrap.