Insulation distribution with a low ceiling; efficiency vs. comfort
Context: a 14′ x 7′ x 6’8 tiny house built on a step-van chassis. Heated by wood and propane. Designed for Zones 4-7. Primary occupant 5’10 or so. Insulation is reclaimed polyiso, mostly 4″ with a few 2″.
If I increase insulation at the roof and lower it a the floor (say, 2″-4″-6″ floor-walls-roof), this would retain the most heat overall, and conform to standard building practice, but wouldn’t it also exacerbate a temperature gradient between air at the roof and air at the floor? For comfort with such a low ceiling, I ideally want the upper air colder (on my face) and warmer (on my feet).
Instead, suppose there were an even 4″ all around; would this keep the floor slightly warmer and the roof slightly cooler, compared to the 2-4-6, at the cost of increased total heat loss?
As a side note, is it wise to have less insulation on the floor than the walls, if the floor is a foot off the ground with no skirting?
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