Most PIR motion sensors, including the Iris brand, Don’t work well outdoors for two reasons.
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they aren’t weatherproofed
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Way too many false alerts. Just a gust of air or a cloud passing over the sun can create enough variance in temperature that you will get an alert. This issue is so significant that Aeotec, for example, recommends that you disable the motion sensor part of their multi sensor if you were going to put it outside.
You can certainly try it and see if it works in a particular location where you want to use it. But it won’t be a surprise if it doesn’t.