As you might expect of a super-hard, super-tough substance that sprays as a liquid and thus plugs any available route within walls, Air Krete presents an impenetrable barrier to pests. But the mechanism isn't what you might think.
Air Krete dries to a porous, almost pumice-like consistency, trapping air bubbles inside the same way traditional insulation uses a latticework of fiberglass fibers to trap air. It's this "air" and not the "krete" that actually does the insulating. And this dry, pumice-like lattice sucks the moisture out of anything it touches, pests included (imagine touching a very cold ice cube with a wet finger -- it sticks).
Needless to say, pests would rather their moisture and oils stayed on their insides, so they tend to avoid Air Krete like kids do brussels sprouts.