Before adding another shelf, check the lift.

The space above a stack is useful only when you can remove what is underneath.

A shelf riser divides one tall shelf into two shorter spaces. That can make a short stack easier to separate from nearby items, but it can also create a cramped lower space that is awkward to use.

Measure the object and the movement

Write down the height of the lower stack and leave room for your hand to lift or slide out a piece. Check the available height above the proposed riser as well. Measure the opening where the riser will enter, not just the interior shelf.

Look closely at the legs. Their positions reduce the usable width below the platform. Product photos may show a stack that is narrower than yours. Use the specified dimensions and load rating for the exact model rather than estimating from the image.

Consider a no-purchase change

If your cabinet has adjustable shelves, an existing shelf may be movable to a more useful position. Follow its hardware instructions and keep supports secure. Do not improvise a load-bearing stack of loose objects.

The decision is simple: can you remove the items you use without dismantling the arrangement? If the riser adds another obstacle, leave that space open or relocate the seldom-used pieces.