Robert Allison wrote:
As to your original problem, you should just install fiberglass batt
insulation between the floor joists. That would go a ways towards
eliminating any coldness from the floor. BUT, the floor is most likely
not the problem as it is rare that a floor will allow a room to become
too cold. Most heat loss is from the walls, ceiling, and especially
windows. I will bet that this alcove has windows on three sides,
doesn't it?

Didn't follow the whole thread, but particularly if the crawl space is
ventilated and the floor is solid, I can see it being a significant heat
loss component.

The hADt term doesn't care in which direction dT is...

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