Most bed support slatting is made of solid wood running face up from bedrail to bedrail. Solid wood planks are not meant to support a load in that orientation due to the nature of the material. It gives and bows in this orientation, and that allows for movement of the mattress when shifting in bed. The proper way to support a mattress is to run the slats on edge and have each slat be at least 3" wide. My slatting system creates an ultra ridgid platform for the mattress to eliminate any movement within the bed.