Originally Posted by ImPreSiV

John - most house alarms have a buffer zone between the ground and 40cm high for example, which can be adjusted, to allow for pets (cats, dogs etc...) or will only detect things over a certain weight - ie: a person from 50kg upwards.. allowing your 25kg labrador to run around as he pleases... if you get robbed by an annorexic though, you have a problem..