Conventional precautions against pests should be more than adequate for straw bale. Some concerns have been raised about hay fever, toxins and pesticide residues. Of course, once the bales are encased in plaster it is difficult for irritants to transfer into the dwelling. Clean, dry bales contain few molds or pests. And pesticides, at least for rice straw, are used early in the growth cycle, then discontinued.
Rice straw contains extremely small amounts of pesticide residue.
A. Test results show straw bale construction to be exceptionally resistant to fire. And, since plaster applied to the uneven bale surfaces tends to be thicker than normally found on buildings, the bales can be said to carry an extra layer of protection. Loose straw, which is sometimes used to fill cavities, is much more vulnerable to fire and should be dealt with carefully by sealing with plaster or treating with fire retardants. Intermittent moisture is not a threat, however. In California, we can face periods of intense rain, usually followed by dry, windy days, excellent for drying out walls.