What alarm sensors for garage?

[CIS121]

I've got a Response wireless alarm for the house an dam going to add some sensors for a new detached garage that backs onto another road.

I'm thinking 2 magnetic sensors, but am unsure if a PIR one is going to get false alarms in a garage from insects etc. What have you guys used?

[Sixpackpert]

Our alarm guy recommended door contacts only because of the problems with PIR's you have already mentioned.

HTH

[Paulbav]

PIR and Microwave dual technology sensors would be fine but not sure you will get them for that system though?
If you can find them just remember to keep the MW level so as it doesn't penetrate out through the walls.