Shed alarm

[combi6793]

Hello,

I'm hoping for economic and straightforward suggestions to alarm a shed. It's a wooden shed, approx 20ft x 30ft, and about 1.5ft above the ground on stilts. It has mains power. There has been a rise in crime in the area recently so I would like to alarm this shed as it is a little secluded from the house and has some valuable equipment in it. One of the people who uses the shed has special needs so I do not want to use a key pad or timed entry system. I know it would not work in a power cut, but I would be happy with a mains only system if it simplified things

Instead of a keypad I think it would be possible to hide a switch under the floor of the shed that is accessed from the outside. There could be an discreet indicator inside the shed like a blue LED near a window or something to show to was on. I think it would be sensible if the alarm could be triggered by a door contact switch or PIR. I am thinking of an alarm that would trigger a loud siren rather than a silent alarm.

TIA

[Tim Watts]

I would put a reed switch behind the wood panelling in a known but unmarked location and use a neodymium magnet as the "key". Unless someone observes you in action, there is no visible mechanism to attack.

[Adam Aglionby]

Something along lines of:

takes a PAYG sim card and phones a number in case of alarm along with siren, key fob control possibly suitable for people of limited mobility also has panic button which will also dial all numbers stored., tend to be a range of sensors available, PIR, door contact etc Usually open collector output available for triggering relay for lights etc.

Limited battery backup ,but cutting power directly before forcing entry won`t help any intruders.

Had similar installed for nearly 2 years, initial false alarms to do with PIR placement ironed out , been stable since. well under 100 quid at time.

Physical security in way of real padlocks and pad bars or decent shackles on solid doors be first line of defence.

Cheers Adam

[ss]

You can also buy for around £9 alarms that pull out a pin when the door is opened and sets an alarm off, the pin is connected to a short length of string (you can make this longer) I have one on the door and another looped through some items in the garage so if they disturb those items the alarm goes off. I just undo a clip to deactivate (this stops the pin being pulled, disconnects the string from the pin) it can be deactivated / reset by a 4 digit code but I never bother.

[Tim Watts]

This is all true - but on the basis we're dealing with thick pikies in the dark rather than Thomas Crown... :)

[Dave Liquorice]

I had similar but instead of the ultrasonic transducer it had some

4mm sockets to connect radio gear to the cars 12v. Guess when that car was knicked? Yep when the flashing LED wasn't for some reason...

[root]

I'd go for deterrence rather than an alarm. People ignore alarms until they become a nuisance and by then whatever damage/theft is going to take place has already happened. Personally I'd go with a proximity detector that either yells at the approaching individual: "Oy you, get away from there" or sounds like a large dog.

[fred]

In article , [e-mail] writes

I agree with the loud sounder approach, I have always put a deafening sounder just inside the main entry point of any place I am trying to protect.

This one is internal but recommended:

has a moving coil element which IME means a more penetrating sound and makes it more noticeable over long distances. Far better than piezo element Sound Bombs IMO.

External boxes are often overpriced and have poor sounders, I prefer to buy a dummy and fit the guts of the above sounder or the SAB variant:

with a strobe:

a door is likely to be kicked in I'd put a shock sensor on it:

a little relay jiggery pokery I'll let a light kick or 2 set off the sounder for the duration of the shock sensor trigger. Most panels can set a trigger count on shock sensors so you can avoid false triggers unless the perp repeatedly triggers the sensor.

In closing I'd definitely say get something with a GSM (or some kind of wireless) link, ideal for slightly remote protection.

[Dave Liquorice]

above

With a nice hidden area underneath with a reasonable space to work in the floor is probably the weakest point...

[combi6793]

It's a wooden shed, approx 20ft x 30ft, and about 1.5ft above

Thanks for your suggestions everyone.

I've been thinking. I have seen a light switched on by a PIR for sale for less than ten pounds. I could fit that inside the shed, switched by a hidden external switch. I could then attach a wire to the bulb terminals running to a siren. Assuming I could find a suitable siren I could fit it externally in a dummy bird box of some kind. Okay I would loose the door contact switch but it could still be good enough, and pretty cheap.

What does the panel think?

[NT]

What use is the key if you dont know where to put it? Good idea imho, if you can ensure noone ever sees you use it. If they do though, its useless.

Dont even think about using magnetically operated contacts on a shed door. They'll be so unreliable as to be quite useless. A PIR would be good.

And do make good use of the element of surprise. If the alarm triggers, make it scare the sht out of them. A 500w bulb will ensure they cant see a thing, but everyone can see them.

NT