AEC & BIM Knowledgebase Error Solution Guide Slabs Slabs Messages in slab controls and possible solutions are listed under this heading. Insufficient Reinforcement on Slabs Punching safety is not provided. The rib height does not meet the requirement in gear upholstery. The slab thickness does not meet the requirement. Slab thickness is insufficient Slab deflection limit exceeded Slab thickness for punching reinforcement min. Should be 25cm Rib spacing and Rib width controls are not provided on Ribbed and waffle slabs. Slab Stress Check is not Provided Next TopicInsufficient Reinforcement on Slabs ×