One panel, one controller, one log. It records which flat answered and which flat released the door, and flat 9's handset was taken off the wall and the cable cut back five years ago.
I chair the residents association of a block of thirty two flats and I have the door entry system in my remit, which nobody else wanted.
What it is: a panel outside with a button per flat, a controller in a cupboard in the entrance hall, and a handset in each flat with a speaker and a door release button.
What it does is a series of closed circuits. You press a button, the controller rings that flat's handset. The resident lifts the handset, which closes a circuit at their end, and the controller connects the audio. They press the release, which closes another circuit, and the controller fires the lock.
The controller logs all of it. Time, flat called, whether the handset was answered, whether the release was pressed. It holds about four thousand events and we download it when somebody complains about the door being on the latch, which is monthly.
The reason it logs is insurance. After a break in in 2018 our insurer wanted evidence that the entry system worked, and a system that logs is cheaper to insure.
Flat 9 is on the first floor and it has been empty since the April of 2020.
The leaseholder died. There was no will anybody could find and it went to the Treasury Solicitor, which is what happens, and it has been going through that process for five years, which is slow and completely ordinary.
The flat is boarded. There was a leak in 2020 that took out the bathroom floor, and the managing agent boarded the front door with an eighteen millimetre ply sheet and a hasp, and the ply is still there and I have a photograph of it from last month.
When the leak was dealt with the handset was taken off the wall in flat 9, because the wall it was on came down. I watched the electrician do it. He cut the four core back into the conduit, put a blanking plate over it, and wrote it on his sheet.
So flat 9 has no handset and no cable at the flat end.
The controller logs flat 9 answering the buzzer.
Between eleven and twenty times a year since 2020. It logs the call, then it logs the handset answered, then it logs a door release.
Which means somebody outside pressed button 9, and the circuit at the flat end closed, and the release circuit closed, and the front door opened.
I want to put the obvious things to bed because I have been round all of them and one of them took two years.
A short in the cable. This is the right answer and it is what I believed until 2022. A four core cut back and left in a conduit can short across, and a short at the flat end looks to the controller exactly like a handset being lifted.
Two things killed it. First, a short is permanent: it would look like flat 9 answering every single time the button was pressed, and it is eleven to twenty times a year against several hundred presses of that button by people who have got the wrong flat. Second, we had the riser rewired in 2023, the whole thing, new four core to every flat, and flat 9's pair terminated in a junction box in the hall cupboard with the ends separated and taped.
It carried on.
The panel. Replaced in 2021 and again in 2024, different manufacturer the second time, which meant a new controller and a new log format.
Flat 9 answers the buzzer.
The times are the part that stops it being an electrical story.
Two in the afternoon, mostly. The spread is 13:40 to 16:20 and I have all of them.
That is not when anything odd happens in a block of flats. That is when deliveries happen.
And the calls are short. Eleven to thirty one seconds between the answer and the release, which is exactly how long it takes to say hello, who is it, it's a parcel, come up.
What happens after the door opens.
Nothing, as far as I can establish, and I have tried hard.
There is a camera on the entrance hall, which came with the 2021 panel. It records to a box in the cupboard, fourteen days.
I have caught four of them.
In all four a delivery driver comes in through the front door, ordinary, holding something. Three of them go up the stairs and out of shot. One of them stands in the hall for about nine seconds looking at the boards on his phone and then goes up.
All four come back down, between two and five minutes later, without the parcel.
The parcels.
I have knocked on doors. Not all thirty two, but the eleven on the first floor and the eight above, over two years, asking whether anybody was expecting something on specific afternoons, and getting the look you get.
Nobody on the first floor has ever had a parcel on one of those days that they had not expected, and nobody has had one go missing.
So somebody is buzzing flat 9, being let in by flat 9, carrying a parcel up to the first floor, leaving it somewhere, and coming back down.
I went up once, straight away, which is the only time I have managed it, in the September before last.
I was in my own flat on the ground floor with the log open on a laptop because I was doing the monthly download, and it happened while I was looking at it. 14:51, flat 9, answered, released.
I was in the hall in about eleven seconds and on the first floor landing in about twenty.
There was nobody on the landing. Both stair doors were shut. The board on flat 9's door was on, the hasp was padlocked, and the padlock is one I fitted and I had the key in my pocket.
In front of the board, on the doormat, which is the original rubber mat that has been there since before the boards went up, there was nothing at all.
I stood there for a while and then I went back down, and the driver came out of the door to the bin corridor about a minute later, past me, and said afternoon, and went out to his van.
I did not ask him anything. I have thought about that a great deal and the honest reason is that I could not think of a question that would not have made me sound exactly like a man who needs to be reported to somebody.
What I have done is nothing that would satisfy a surveyor.
The system's log is downloaded monthly and filed, because the insurer likes it and because I am the kind of person who files things. Flat 9's events are on a separate sheet now and the sheet is in a folder in my flat.
The managing agent knows the handset is disconnected and has the electrician's certificate saying so, which is true.
And in the April, when the Treasury Solicitor's process finally moves and somebody buys that flat and takes the boards off, I am going to be somewhere else.