...enters the building. I will have to take a small exception to the word "toxic" relating to the styrofoam materials. The plastic itself is "safe" enough to be used in a variety of human-food-grade containers, and the ever present disposable coffee cup would be the best example. It is approved to serve scalding hot acidic liquids, which would be a major no-no if there was any inherent toxicity to the plastic foam material. Now I CAN agree there may be a risk of a lizard getting a mechanical blockage from ingesting the loose beads of styrofoam, should they have access to a bare spot in the mortared material. I have tried standard masonry mortar as well as the thin-set sanded grout, and both materials seem to produce a very hard and durable shell over the foam, if properly mixed, applied in sufficient thickness and cured. Inspection of the finished surface is pretty important, as its possible to get a thin coverage in spots which will probably NOT cure as hard and could be punctured somehow. I'd say the temps during the cure are worth noting, as some of these mortar materials are ruined if exposed to freezing temps before complete curing. The handfull of fakes I've played with so far are VERY hard shelled and could NOT be damaged by anything a collared lizard could do. I have looked at sites which use the 'aerosol' cans of expanding foam, and if they are anything like some of the materials I've used in the pattern shop, you might want to look over the ingredients of THOSE materials pretty closely, as some of them actually could have toxic chemicals present. If you have any information you can cite (and post) on the toxicity of "ordinary" styrofoam, I'd certainly like to see it.
DC
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