It is very important to install as to alert something /someone is in your roof. Look for quality pir , pet immune and auto temperature compensation is a must to prevent false alarm.

Also better to add cctv in the roof as you can see whats happening .

This post has been edited by pg84: Jun 26 2014, 11:18 AM

for me i placed it on both opposite edge of roof , and the cctv just above the sensor . Any wind blow grass moves , just need to look at cctv.

then its better to change it to auto temp compensation type.

ya 2 is enuf , cctv is in the roof la , cannot see outside mah

I think paradox ones have...pls google