Indoor hot tub concerns
I’m proposing a 360 sf, one story addition to be constructed in southern NH using 4.5″ polyiso SIPs for the walls, and high density cellulose blown into the scissor trussed roof/ceiling. Inboard of the SIPs we’ll be framing a 2×4 wall for additional insulation as well as a place for the wiring. The addition will be open space that will include a 4 person hot tub. My concern is the potential for excessive water vapor from the hot tub especially in the superinsulated and air tight shell that we are proposing. The owner assures me that the lid on the hot tub will be in place the majority of the time.
I know there are a number of other variables to consider, but I’m wondering if we should just move ahead with the project and monitor the humidity levels after construction is complete (being prepared to react accordingly), or should we be planning to install a HRV system.
I’ve never done an indoor hot tub, and from those I’ve seen, excessive humidity doesn’t seem to be an issue.
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