Help.Snake under floorboards!

Question
My daughter recently got a bairds rat snake and whilst handling him yesterday he escaped.Though we tried to grab him and put him away he managed to get down a small hole in the floorboards.I'm confident he can only roam under the flooring of our home as the walls are brick on all the boundaries,but we live in a block of apartments and am worried he may "pop out" on the neighbours below.He is about 3 feet long but a bit thin and had a good feed a few days ago.I've read suggestions for "traps" and will try all possible ideas.I have a young cat(7 months old) and 2 young children also so am concerned we'll never see the snake again.His cage is very close to where he went down.How often would you suggest baiting the trap and have you any other suggestions for tempting him back up from the floorboards?We did look everywhere in the room including inside furniture,clothing,boxes,etc so we know this is the only place left he could be.

Answer
I have seen snake traps on the internet but I really have no experience with them. Every time that I have lost a snake in the house it's made his way back. Sometimes it took a couple of months though. I really don't have any suggestions on how best to catch it though.