"BigWallop" wrote
| You'd be better off with an actual fire control panel and detectors,
| rather than mains cables running everywhere.

Interconnected smoke alarms usually require only *one* triple+E cable to
provide power and interconnect functions.

Most conventional fire alarm systems will require either 2 x twin, or 1 x
triple, for detectors and sounders. There are single-cable systems but they
tend to be more expensive.

| Run your detectors in normal PVC T&E but make sure the sounder /
| alarm bells are made in flame proof cable.

I *think* the updated BS now requires detector cabling in fire resistant
cable. Many panels specify screened cable anyway, either Firetuff or MICC,
for electromagnetic compatibility.

| One control panel with 3 or 4 zones is very cheap, and only one
| battery to replace in 6 years time.

To comply with BS, fire alarm systems require periodic testing and
maintenance on contract. That's an unneccesary complexity and expense for a
domestic system, and may compromise safety. A cable break will show a fault
on a panel system, but could still knock out *every* detector and/or
sounder. In a workplace there will be a maintenance contract and a procedure
to call out a technican promptly to attend to this; a home user is more
likely to switch off the panel and then forget about it. A cable break on an
interconnected system should leave some alarms still working.

Moreover, interconnected smoke alarms usually provide a self-resetting hush
function, which is comparatively rare (and might not be permitted by BS) on
panel systems, yet is very useful in a domestic environment to minimise
false alarms.

| I do think you'd be better with a fire alarm system all in one.

In a single family dwelling with half a dozen detectors?

Owain