Kevin wrote:
....
seem to recall that at the time the Title 24 calcs were done, being told
that an exposed slab, would have a positive effect on the calcs, but a
carpeted floor wouldn't figure into the equation.

That doesn't make any sense--if a slab has an effect but changing the
slab to something else doesn't, then that fact "has figured into the
equation".

This addition is in the half of the basement area that wasn't already a
finished room. The pre-existing half does have carpet, and in the hot weather
we are currently experiencing, I'm noticing that the new room does stay
cooler than the pre-existing room.... (I don't have a/c for the lower half
of the house). I would like to keep it that way, and
am wondering if carpeting will have a noticable effect. My alternative to
carpet would be real linoleum, which I'm assuming would have a very limited,
insulating effect.
....

And, it'll be exactly the opposite effect when the cold weather arrives.
Of course carpeting has an insulating effect; just how big an "R"
factor it is depends mostly on how think the pad used is; the carpet
itself is a lesser (but not totally negligible) amount.

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