I just wanted to share my experience installing a Sleep Master Platform Mattress Foundation with a King size High back Malm Bed from IKEA.
I assembled the bed without the included rails and without installing the center support beam which is sold separately from IKEA.
Then I assembled the Sleep Master foundation and it fit perfectly inside the bed frame. It is a tight fit, but the frame is fully extended and laying flat without any problems.
I have seen other posts where people have done the same, but in some cases I wasn’t sure if the King size bed would work well and I wanted to comment on the idea some have mentioned of using the IKEA under bed storage drawers. The drawers will not fit, because the Sleep Master foundation has support legs that will block the drawers from being able to slide under the bed.
It seems like a great combination compared to the IKEA slat systems.
I will attach photos.
