I have recently installed cctv at my house but I need some artificial light on a night to enhance the footage. Im have fitted a 15w LED pir floodlight on my garage, 2.5mm2 twe from a socket to a switched fused spur, to the floodlight, but I also need to fit one on the front of my house. The light would be 30w/50w LED on the front peak above the window so lighting cable coming in through loft space, can I connect to the existing upstairs lighting circuit and if so what would be best way? Cable size, fused spur etc.