One of the questions we are asked is “will raising our concrete damage it?” With over a thousand jobs under our belt and thousands of slabs raised the answer is generally no but it is something that is hard to predict. Some of the most gentle lifting on minor settling may generate a crack whereas a huge lift may not. Why?
- Concrete of a thickness of less than 5″ is more prone to cracking, unfortunately this includes nearly all the poured slabs out there. Slabs 4″ thick are twice as resistant to fractures (heavy loads from above as well as lifting from below) than are 3″ slabs. The problem is slabs may be 5″ thick in one area and 2 1/2″ in another. Because we can’t know where a thin spot may be we may attempt to lift from the weakest spot on the whole slab which may generate a crack.
- Occasionally a slab may bind on something such as a foundation wall or another slab which can cause a crack. Most of the time slabs bound on other slabs are simply cut free of each other which eliminates the problem. Slabs bound against foundations generally can’t be cut free and if stuck cannot be raised without risking cracking.
- Finally, there are often cracks that are invisible to the untrained eye already in your slab. These cracks are often in areas that have settled slightly and pinched the crack together or the slab hasn’t been thoroughly cleaned and the cracks are filled with dirt or sand which conceals the fractures. Either way when raised the cracks will open up to some degree when leveled or raised.
In the end the consumer accepts the risk of a cracked slab either when hiring a replacement concrete contractor or someone to raise their concrete. By hiring the most experienced contractor whether replacement or repair you have less chance of a cracked slab when complete. For concrete raising that contractor is Slabjack Geotechnical.
Call today 1-855-752-2522
Superior technology, Superior polymers, Superior results.