Curious to know how the following confined space issue would be presented\worded in your inspection report:
I have a gas fired water heater and furnace, both vented VIA chimney, with an aggregate of 120k BTU/h.
50 cubic feet of combustion air needed per 1k BTU/h, which puts me at 6k cu ft combustible air needed.
The room this equipment is located is in a basement, is roughly 870 cubic ft, and incorporates a 16.25sq ft door opening, with no door attached.
The room adjacent to the equipment\door opening is 3,249 cu ft, which puts me at 4,125 cu ft. So I’m shy 1,875 cu ft of needed air.
It should be noted that the ‘adjacent room’ incorporates the stairwell to the main floor, with a door at the top of the stairwell. The stairwell space is roughly 110 cu ft - still well below what is required.
Also of note is this scenario applies to my house, which I’ve lived in for 20yrs. I’ve never had any issue with negative pressure impacting the water heater venting (smoke test), and don’t believe the lack of combustible air was flagged as ‘defect’ when my inspection took place (although it’s hard to recall after all this time). I do recall the inspector telling me verbally to never put a door on the utility room.
I know I’m going encounter this scenario once I start doing inspections, hence the question to those with first had experience.