When that foil insulation first came out, I had an industrial use for it but had to provide the Rvalue (insulation value). It took quite a bit of research as the insulating value can’t be calculated the traditional method because of the reflective surfaces on both sides. It was different than fiberglass or styrofoam. Anyways when the answer finally came back, it was the equivalent of 6" of fiberglass insulation…R28…think your observation hive will be just fine.
In one of our beehouses, we lined the inside of our beehouse with foil insulation plus we had R15 (3") fiberglass insulation in the framing…bees loved it.