I've not had one false alarm, they've never failed, and they're nowhere
near furniture.

You will. It's just a matter of time.

If they're simply thrown under a carpet, yes. If they're cut into the
underlay they're undetectable - unless you're really checking for them

Oh so the bump becomes a dip instead of a bump! Oh please!

They also wear out as we stand on them in normal day to day living.

Mine are in the most heavy trafficked part of the house - and are fine.

Have you looked at them? Checked their condition? Is the foil and foam
protruding from the split edges yet?!

I've been burgled once and had a couple of attempts (before the alarm was
fitted). Each time they levered open - or attempted to - a sash window.
Most casual burglars don't want to crawl through broken glass - would you?

Yes, if I did it for a living like burglars do!

Contacts
on doors is also (in my opinion) a waste of time - except when necessary
to start a setting or an entry procedure. Doors and windows should
always be locked and bolted thus rendering any contact useless in
anything other than a complete gross attack.

Of course they're locked and bolted. But on a wooden sash, such locks
won't resist a determined attack with a jemmy, etc.

The PROPER locks will.


I specified alarm systems for over 25 years and always avoided
contacting doors and windows (front door was usually contacted to form
the exit/entry route) and as soon as space protection was introduced in
the late 70's pressure pads were dropped like a very hot brick in favour
of them. Ultrasonic first, then PIR's and microwaves etc.

Pressure pads?! I suggest contacting your local museum as they may be
interested in buying them from you!

Strange how I never have false alarms - unlike the professionally fitted
systems either side of me. ;-)

False alarms are caused by two main factors - pressure pads and poor
installation techniques such as not soldering joints etc. I happen to know
this as I've been an alarm engineer for many many years, unlike yourself.