How to insulate & air seal an addition built on an existing deck
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| Posted in Green Building Techniques on
I have a net zero energy home (EUI 13 KBTU/SF/yr). I plan to enclose an existing 8’ x 12’ deck to create more interior space. The deck is attached to the house and supported on 4 concrete piers, which we want to retain. I am also considering a cathedral ceiling in the new space. Can I get advice on how to insulate and air seal the floor of this new room, which will be exposed to outdoor temperatures, and the ceiling, which will have no attic above?
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Replies
Courtney,
It seems odd to go from having a net-zero energy house to wanting to retrofit such a deck to living space. I imagine this would be an extremely tall task if you want to remain anywhere near net-zero. You would be adding an incredible amount of exterior surface area and minimal volume.
But what climate zone are you in? I have a cold weather bias.
Did you have the original house built? Is that builder still around?
It's hard for me to see how you can effectively retrofit a deck to become a highly efficient envelop.
The search feature on this site can bring you to many helpful articles however.
Such as:
https://www.greenbuildingadvisor.com/article/how-to-build-an-insulated-cathedral-ceiling
https://www.greenbuildingadvisor.com/article/sealing-a-crawl-space
Thank you. I plan to maintain the existing house envelope. This new room will be more like a porch but warm enough in a Connecticut winter to be used by someone who isn't too sensitive to cold (me).
The space under the deck will not be enclosed so the crawl space article would not apply. I suspect I should build the floor of the new room like a wall.