Is post tension slab more expensive?
Post-tensioned concrete will usually be more expensive for the home builder, due to the extra equipment needed. However, in large structures, post-tensioning can actually be less costly than conventional concrete slabs.
Is a post tension slab better?
First off, one could argue that post-tensioning is superior to conventionally reinforced concrete in a pure engineering sense. The reason is because post-tensioning is a method of pre-compression, which means the concrete is put into a state of compression, which allows the concrete to take on flexure without cracking.
How expensive is a post tension slab?
Generally speaking the perception is that a post tensioned sport court is more expensive than a cast in place slab. So we dug into it and got some installed numbers. What we learned is that they are virtually the same price at about $4.50-5.00 per square foot when the cast in place slab has rebar at 18″ centers.
How long does post tension slab last?
about 15-20 years
Conventional concrete & rebar foundations last about 20-30 years before failure begins to occur. Post-tension slabs are lasting about 15-20 years and are failing at a much higher rate. Post-tension slabs are created with concrete trenches around the perimeter of the house where the external walls will be placed.
What are the disadvantages of Post tensioning?
Disadvantage of Post Tension Slab
- Skilled Labours. Post tension slabs require skilled workers.
- Poor Workmanship. This type of slab requires special skills.
- Poor Compaction. A number of tendons used in post-tension slabs are prone to corrosion.
Do post tension slabs have footings?
Now, what makes them different from your conventional slab foundation system is that post tension slab foundations typically don’t have standard footings at all. They don’t have deep footings around the perimeter of the home or under load-bearing walls within the structure.
Should a post tension slab crack?
Small cracks do not normally create a significant concern other than for cosmetic reasons or those associated with pest control and are considered insignificant once the tendons are tensioned.
Does post tension slab crack?
Cracks more often occur during curing because the concrete generates heat and expands during the chemical process and shrinks as it cools. Because there is not yet tension on the tendon cables there is no reinforcement to hold the foundation together and cracks often occur during this period of time.
Is rebar used in post tension slabs?
Post-tensioning, which is a form of prestressing, has several advantages over standard reinforcing steel (rebars): It reduces or eliminates shrinkage cracking-therefore no joints, or fewer joints, are needed. Cracks that do form are held tightly together. It allows slabs and other structural members to be thinner.
How thick is a post tension slab?
Basic Overview of Post Tension Foundations A post tension slab foundation can range anywhere from 4 to 12 inches thick.