I’d imagine it has to be a regulatory nightmare. There’s really no options on the market. First alert at this point just has the zwave one that can’t be hardwired or interconnected so it’s not to code in many locales. Nest is pretty good but it won’t work intranet only and that’s a dealbreaker for me; I do iot but it has to be gear that can cope with being on a vlan with no internet access. The only other options are sketchy brands that don’t give a fuck about us regulations. Sometimes it’s a chinese company that has some staying power like xiaomi but sometimes it’s one of those random ones that likely won’t exist in 2 years

A shame because I would really like to be notified if my house is burning down while I’m away from it. Would be pretty handy.