The maximum span of a post tension slab depends on several factors, such as the slab thickness, the tendon layout, the concrete strength, the load intensity, and the design criteria. However, some general guidelines can be found in the literature based on typical applications and experience.
According to one source1, the maximum span of a post tension slab can range from 25 to 40 feet (7.6 to 12.2 m) for two-way slabs, and from 30 to 65 feet (9.1 to 19.8 m) for one-way slabs or beams. Another source2 suggests that the maximum span of a post tension slab can be up to 45 feet (13.7 m) for joist systems, and up to 35 feet (10.7 m) for beam systems. However, these values are only approximate and may vary significantly depending on each project’s conditions and requirements. Therefore, it is advisable to consult with an experienced engineer or contractor for more accurate information about post tension slab design and construction