Many thanks for the extra replies guys.

I am also worried about the poisoning. I'm really not a rat expert at all. So I don't know if this rat(s) now lives in the loft or does he wander in and out of there as part of his daily routine? So does ratty exit the house daily and go about his business up the garden etc? If he does exit the house then is he likely to eat the poison and then make it out of the house and die up the garden? I have dogs and I don't want them munching on a dead rat full of poison. Also loads of cats coming into the garden and I don't want someone's cat poisoned.

I'll ring the council on Monday and see what they have to say. A good excuse to clear a load of stuff out of the loft and lay a few traps my side.

Thanks again guys. Much appreciated.