Stools are used to separate the top reinforcement mesh and bottom reinforcement mesh. It’s essential to maintain the accurate thickness of the slab. Dimensions of the Stools could be changed as per requirement. Those should be strong enough to bear the loads without changing the gap between the two layers.

The height of the stool can be calculated as follows,

Stool’s height = Slab thickness – (2*cover + diameter of the top and bottom bars)