I have neighbours who live directly in front of me - the back of their house and the front of mine are separated by a driveway which feeds my house and another neighbour to my right. They have a deck that wraps around the back of their house, which they have done all sorts of non-code things to, like enclosing parts with laser-lite panels, dodgy electrics fed out of windows, an outdoor kitchen, and have what appears to be several large-format digital printers on it (and associated inks/chemicals), along with a pile of household junk.
About two weeks ago something on said deck started beeping. It's intermittent during the day but always beeps consistently at night. I can hear it in my house with all the doors and windows closed. It sounds exactly like a smoke alarm when the battery is running down - a loud 'chirp' every 35 seconds.
Is there anything else that would make that noise? Like some kind of security system? It seems like it is being turned on and off since it mainly beeps at night, but I can't imagine any system that would do that because of the nuisance factor. I do recall seeing them attaching something to the wall of their house around the time the noise began. If it's a smoke alarm with a dying battery, how long might it beep before it dies? If it's an indoor alarm they've used, could it be beeping because of the temperature outside?
I intend to pop a polite note in their letterbox (maybe with a fresh battery) but would like to know what I might be dealing with first, and I can't see what it is because of all the junk. They have a double mattress stood up in front of where I think the device is, and a hot water cylinder and a BBQ in front of that (what a lovely view I have from my living room window).
If they refuse to deal with the beeping, is there anything I can do? Does that kind of noise fall foul of noise regulations? Can I insist they sort it out or am I stuck with it? I can't imagine what it will be like over summer once I open the windows in the evening.
All advice gratefully received.