I just purchased a new Ultimate Dreams King Size Supreme Gel Memory Foam Mattress (which I don’t seem to see reviews of on this site, so I’ll try to put one up after it’s delivered), and had a question about the bed. We have a king size bed already, with slats that are a bit more than 3" apart. What’s the best way to modify this for the new mattress? Should I get wider slats so that they are spaced closer together? Should I just buy some plywood or fibrewood to lay on top of the slats to make a single flat surface? Do I need to add additional supports?
The Supreme Gel is one of their newer mattresses so there haven’t been many reviews about it yet. One of the members purchased it here but unfortunately they didn’t come back and share their feedback.
The 3" or less" guideline is for mattresses that use latex in the bottom layer. Your mattress uses polyfoam which is not as elastic and stiffer so if your platform slats are a little over 3" or even wider apart than that it will be fine and you won’t need to adjust it at all. The suggestions on the Brooklyn Bedding site here is 8" or less but I also wouldn’t choose slats that are that far apart.
It seems to me that what you have will be fine as long as there is a midbeam with good support to the floor…