I figure once we stuff ours closet full of clothes, linens, and what not it will be well insulated! LOL
At least for hot/cold transfer into the bedroom. Our front faces the west and takes the full brunt of the afternoon sun and heat here in central Florida. Although warm in the closet ( and not unbearably warm I might add) we've not seen it adversely affecting the performance of the two ac units ability to cycle on and off or our ability to maintain a reasonably cool temp throughout our 36FB.
Walk lightly upon Mother Earth and leave no footprint behind.