@mattblaze "All due consideration" is doing a bit of work here.

@mweiss @mattblaze Where I live, of you do any renovations that require a building inspector, you have to install wired smoke detectors. (I presume they have some kind of battery to backup for power outages - the last one at our house was 5 days) (Also, we got a building inspector who didn't mind not noticing what kind of smoke detectors we have, because installing wired smoke detectors would have required major rewiring)

@mattblaze I recently replaced my end-of-lifespan (10 yrs) smoke detectors with new ones that claim their battery lasts 10 years.
(IIRC, there's a speck of radioactive material in them, whose decay determines the detector's lifespan)