How do I prevent lights being on permanently

[kelfoan]

I have a light switch which controls the outside porch light and the spot lights along my garage. These lights work via a simple 1gang 1 way switch. I want to replace the porch light with one that has a nightime sensor , however I will have to have the switch permanently on. This means tht although the porch light will only come on at dusk, the garage spot ligts will be on all the time. How do I seperate the 2. I dont want to start adding extra switches as i have only just decorated

[Seventhhouse]

It depends on how many cables, or cable cores are behind your light switch, If both the porch and the garage lights are fed from the switch and can be separated, you could use a double switch - available in a single pattress.
If there is only one cable or pair of cores, you could intercept the cabling between the porch and the garage, and install a PIR for the garage lights.
The switch permanently on; the porch triggered by a photocell and the garage spots by PIR.