Unvented attic space in 1930s Cape Cod
My wife and I are in the process of doing a kitchen remodel in our 1939 Cape Cod (1.5 story) in zone 4A. There are a lot of wonky complications due to previous owner remodels and also just a Cape Cod with dormers.
There was ductwork in the unvented attic space above the kitchen supplying an upstairs bedroom and the first floor kitchen and dining room that we discovered in poor condition so we removed the old ductwork in this small unvented attic space (roughly 5’x9′ on a corner of the roof where two different angles meet).
Now we are trying to figure how to insulate the attic space and after reading about a hundred posts and dozens of articles I feel very unsure about what to do because of our complications and budget.
Complication #1: It is an unvented attic with no overhang at all for adding ventilation.
#2: It shares some sort of thin fiberboard wall with the utility room for furnace and water heater after previous owners converted the garage to a conditioned living space except for the back utility area.
#3: Roof is only about 10 years old in good condition from previous owners but is asphalt shingles on top of wood shingles over skip sheathing (perpendicular 1×4 slats with about 6 inch gaps between them with shingles nailed into them). Roof is constructed with 2×4 rafters
A new roof is completely out of our budget, especially as we plan to only be living in this house for about 3 to 5 more years.
The ductwork and semi-conditioned utility room makes me think spray foaming the interior of the roof deck is the only option, but I’ve seen it mentioned here that you can’t spray foam with skip sheathing which leaves me just clueless as what to do.
Before I opened up the attic space (because of kitchen renovation) there was some kind of very old (about 1/2 inch thick) paper wrapped insulation nailed to the knee walls and someone had put down about 1/2 inch thick unfaced fiberglass in a few places above the old ceiling.
Are there any options here for someone on a tight budget? I’m know that pretty much any option will not get me anywhere near code level of r-38 but what can I do to at least something while I have this attic space open.
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