What is Slab-jacking, and how does it work?
Slab-jacking is a proven alternative to concrete replacement dating back to the early 1930's.
Concrete settles for a variety of reasons. The #1 reason is that the base simply was not compacted properly before the concrete was poured. Over time the sub-base simply fails under the weight of the new slab and therefore settles. Slab-jacking is the proven answer. A series of small holes are drilled in the slab through which a grout and cement mix is pumped beneath the concrete slab. The grout under pressure depresses and helps stabilize the sub soil, fills the void and thus raises the slab to its proper grade. After the slab is lifted the holes are filled and patched with new cement.
The entire process is usually completed in just a few hours, allowing the concrete to be back in use immediately, and at 50 - 90% less than the cost of replacement!
Minimal mess, minimal down time, and as you still have the same concrete, newly lifted areas will still match the color of surrounding concrete. (Only the holes, which must be patched with new cement, may not match perfectly.)
It should also be noted that any existing stains or cracks will still be there as the slab-jacking process elevates the existing slab by pumping grout under the slab. Since concrete will not bend, slabs that are poured with "dips" in it will still have the dips after it is lifted. Virtually all concrete cracks. The crack may be on the bottom of the concrete and not be visible until after it is lifted. Every effort is taken to prevent cracking, however we cannot be held responsible for cracks. Slabs with a few cracks can be lifted by a professional slab-jacker but severely cracked concrete may need to be replaced.
Other factors which can cause concrete to sink are water erosion and rodents undermining the concrete. These are issues which are part of regular home maintenance and need to be checked regularly by the home owner to prevent further problems. Simple steps to take are checking to assure all cracks are sealed every spring (we recommend "Sonolastic SL1" for horizontal joints and "Sonolastic NP1" for 45 degree angles and vertical joints) and make sure all water drains away from your concrete and home. Look for small holes and signs of digging beside your concrete as an indication of rodent activity. Rodents must not be allowed to undermine your concrete. You may need to call a professional exterminator if you can not stop them. Our material will not settle but we cannot prevent erosion or other forms of undermining.