our window keys are a particular brand and apparently they're all exactly the same. So to get a new one you just buy them over the counter in a Mr Minit / Timpson's place. I was a bit by that but the new ones do work!
SPB, pretty much all window keys are like that. I work with rental properties and have to get spare window keys all the time because our tenants lose them. I can't remember the last time I actually had one cut rather than just getting it off the shelf.
Thanks lottiebunny. I'd assumed that was the case but it could have just been ours (Cotswald). Is that not a HUGE security issue though? I suppose it prevents opportunistic theft but any decent burglar will have one of each in his toolbox!
sazm, without window locks, you can smash the glass or cut a hole in it, put your hand through and open the window to gain access to the property. If you have window locks, you can't open it, even from the inside without the key.