I got the IKEA bunk beds a few years ago for my daughter and now I don't remember why I didn't get mattresses there too. You should be able to find out what the maximum height allowed for a mattress is for each set. I think I had to take a ruler and measure it for myself, but I just went to a mattress store and looked for mattresses with a low profile. There weren't that many to choose from, but I did find some comfortable ones.

ETA - A PP mentioned bunkie boards mattresses...I personally used to sleep in bunk beds and the bunkie board was its own thing separate from the mattress - kind of like a really short box spring. The bunk beds I bought at IKEA didn't need a bunkie board, and bunk beds are a b***** to change sheets on as it is so I would definitely avoid a heavy mattress.

Allison

Mom to:
Madeline 09/2001
Jack, Evan & ^Alex^ 03/02/2008 @ 26 weeks