Electrical
Why does my smoke detector keep chirping?
What’s likely going on
A single periodic chirp almost always means a low battery, even in hardwired detectors that have a battery backup. A detector that's simply reached the end of its roughly 10-year lifespan will also chirp persistently no matter what battery you put in, since the unit itself is telling you it's done.
Is this a DIY job or worth calling someone?
Don't ignore this one or pull the battery out of frustration — a working smoke detector matters. Replacing the battery is safe and easy; if it still chirps afterward, the whole unit likely needs replacing, which is worth doing promptly rather than leaving a home without working smoke detection.
Not sure, or ready to have someone take care of it?