I tried 3 different mattresses and 1 new bed foundation in 1 year. My mattress basically is about 1.5 inch higher on one side vs. the other side. it’s like this.
Looking at it from the top, the right side is flat. But as you go past the center point, the mattress rises slightly. It continues to rise towards the left edge to about 85% of the way. Then, it flattens out.
I thought there were something wrong with the mattress. So put the mattress on the floor and slept the whole night without any issue. Perfectly flat.
I thought there were some flexing issues with the foundation. But my level is literally flat when I put it on the foundation after installing it.
I thought perhaps the attachment points on hardwood bed may be different height. They were, but only about 1/8 of an inch difference between left and right rails.
Just out of curiosity, I rotated the foundation (former head side went to feet side) and still have the exact same problem.
this happens with Sealy Posteurpedic, Avocado Green and Sleep On Latex mattress (which is my latest). My next step is to get rid of the bed and get a new one but that is an expensive proposition. Any suggestions or ideas?