Four season room insulation and ventilation
Uninsulated (or poorly.. not sure what the previous homeowners did / the interior is finished) four season room attached to a ranch in climate zone 5.
Bottom of floor joists are covered with plywood.. so not sure what they have in there.. probably fiberglass…
EPDM rubber roof (looks to have soffit vents but not sure what is going on beneath the rubber for venting. As I do not think it vents to the inside of the main vented attic.. so maybe just soffit vents?) with windows all around, and two doors.
It does get icicles .. and part of that I’m guessing is that there doesn’t look to be a good air barrier.. as they used (cedar?) plywood/siding with non-sealed seams instead of drywall to finish the interior
Attaches to the house with leaky glass french doors.
Room is raised off the ground by about 2 feet…1 foot near home (sloped)
Has an electric baseboard for heat but nothing else.. no venting
My question is.. what are the options for making this a more comfortable / energy efficient space?
If more insulation added/ air sealed, will the windows (leaky double-hungs) allow for enough ventilation? Or would this hold too much moisture when humidity was high in summer?
How would you guys tackle a project like this?
Would it make sense to make it apart of thermal envelope? I would guess not being that all the windows make for a large amount of heat loss/gain? But.. would maybe solve the ventilation issue if allowed to breath from main house/HVAC..
From what I have read.. if no venting in roof assembly it should dry to the inside.. so I would think spray foam would be best choice in ceiling and walls since I can’t add rigid foam on the sheathing.
For the floor I was thinking of adding rigid foam to the underside of the plywood on bottom of joists, then adding another layer of wood to protect it and keep out critters.
Don’t need the room to be 70 all year.. so not planning on adding a mini split unless required, just comfortable enough to enjoy and keep humidity under control.
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