Separately supplied and conditioned room within a room
This is kinda a weird question and I searched pretty hard but didn’t find much except a post about a very elaborate gun storage room which was focused on totally different stuff. Google returns a lot of acoustic studio advice which is not exactly relevant either.
I hope the medical stuff doesn’t break any Q&A rules, I included the bare minimum for context.
Unfortunately I have been diagnosed with something called Mast Cell Activation Syndrome (MCAS) and it severely affects my quality of life. Without going into details it’s one of reasons why doctors are thinking some people are very sensitive to things like mold, pollen, VOCs, etc, and others seem to tolerate them with gusto. For me even the mildest of exposures will trigger incapacitating, whole body pain plus other unpleasantness. I haven’t slept for more than 2 hours at a time in 3 years.
Previously I only had mild issues that didn’t cross my mind as medical stuff, until one day I was exposed to a large quantity of lab waste at work without proper ventilation or PPE (someone dropped a container). Now I cannot really work and am just trying to figure out how to spend my retirement savings in a way that will hopefully get me to a place where I can work again.
I currently live in a condo with really bad air quality; it’s downwind of a frequently used parking garage and is also really close by a busy gas station. And to top it off I’m pretty sure the ceiling is showing signs of moisture damage. I’ve had stuff in closets away from the bathroom grow mold, so something is up. I am living with my dad because I don’t have income and he says he has no problems living here, but he’s accumulated quite the laundry list of health problems since we moved in, so…
The number one treatment for MCAS is to reduce exposure to triggers. Obviously I plan to move, but the thought of ending up on a year lease in a place that’s only slightly better without some kind of longer term life raft plan seems a little depressing, and I can’t afford to repeat that process too many times. Also, despite having enough savings for rent, it’s very hard to find rentals that don’t require 3x income regardless of savings here.
I have an aunt who has offered up their porch that has since been converted to interior space, approximately 12′ x 20′ (guessing).
The house was built probably post-WW2, and the pre-existing porch roof is basically the old giant overhang (double height at the old exterior wall). I don’t know the how or if this roof is vented.
Then the added walls are 2×4 framed and sheathed with T1-11 grooved plywood siding(?) with unknown amounts of insulation. I believe the floor is tile over bare concrete slab.
It is in Bellevue, WA, climate zone 4C. I stayed there a few times when I was a kid, and I remember it being extremely cold at night during the winter, even with several space heaters running. Maybe 48-55F? I would keep the single pane sliding door open to the house and move my sleeping bag close to the opening.
How unrealistic would it be to build a room within this converted porch? I was thinking I could make it small, just enough room to safely fit a twin bed, a small computer desk, a portable dehumidifier, a portable air purifier, and heating/cooling (temperature extremes are a trigger).
I was thinking since bulk water is no concern, to build something like this:
Taped plywood (air control layer)
2×4/6 structural framing with some kind of tolerable cavity insulation
2 layers of 40mm(?) Gutex, or cork? with staggered joints
Roof – same idea as the walls but with appropriately sized structural framing, and maybe more insulation? And of course tape the plywood to the wall plywood.
Floor system – this I’m not really sure about. I think the walls would sit on the true floor since I don’t care so much about acoustic isolation. Then I guess stack 2 layers of staggered Gutex or cork on top of the tiled or bare slab and top it with Advantech or similar, taping that to the walls. Then undyed red rosin paper and some kind of floating hardwood floor
Electrical – uhm…put it close enough to the wall with existing outlets that I can just plug things in directly through a gasketed port? As I write this, it already sounds like a bad idea.
Ventilation – two through wall ERVs or a regular ERV to an insulated duct running through the exterior wall. Condensation issues along the duct?
Windows and doors – one good of each in terms of air infiltration. And the window sized for egress. Two windows if in the budget?
Having now written this out, it does sort of sound uhm, not exactly realistic. But as I sit here wondering if for the third year in a row I’m going to spend tonight repeatedly waking up to a vomit filled mouth because the wind shifted…
Problems I could guess about:
-permitting; in searching I only found info about permitting for commercial recording studios built inside homes, but nothing suggesting a recreational studio required a permit. But maybe that’s because nobody sleeps in their recording studios.
-might be a lot of work and money to not solve anything
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