I moved my 2.5 year old to a bed at around the same age and although the first day or two he slept in the bed, his naps started taking place on the floor in front of the door as well. What we did is put two bed safety rails across the exposed edge of the bed to simulate the closed-in feeling of a crib, but in a big bed. Mind you, he was also sleeping on the lower half of the bunk bed, so he really couldn't get out over the rails if he tried. We had to move his younger brother into the crib, so DS#1 made the move. We took the bedrails down about two months ago and he never came off the bed during nap times or night times.