From Jacob’s Desk: How long will concrete lifting last?
With nearly two decades of experience serving Central Ohio, you can imagine how many questions we’ve answered about concrete lifting and leveling! That’s why B-Level president Jacob Shreyer has devoted his time answering your questions in the blog series “From Jacob’s Desk.”
How long will concrete lifting last?
If you’re planning a concrete lifting project and wondering “will my concrete sink again if I have it lifted?” I would have to answer with: “It will never sink, maybe it won’t sink, or it may never stop sinking.”
I know this isn’t the answer you’re looking for but we might be able to determine which category your concrete most likely falls in: “Never Sink, Maybe Never Sink, or May Never Stop Sinking” so that you can make a more informed decision as to the right repair option for you.
How old is the concrete?
I’m sure you have all heard of the “7-year itch” when it comes to marriage. Will the couple make it through the first seven years? If they do, their odds of staying married increases. Ironically, the same question can be asked about concrete when it comes to settling!
Within the first 7 years of the concrete’s life, it is subject to normal construction settlement due to improperly compacted soils. Once the concrete has been down for 7 or more years, the odds of the concrete settling decreases. Having new concrete lifted before it reaches 7 years old puts your concrete in the “Maybe Never Sink” category.
What is underneath my concrete?
For most of us the question of, “what is underneath my concrete,” is hard to answer because we simply don’t know. All we do know is that the concrete has dropped and it’s very possible that whatever is underneath the concrete could have contributed, or be the sole reason, as to why it dropped. This problem extends beyond “improperly compacted soils” mentioned above.
You may be dealing with organic debris such as old tree stumps and roots, or construction debris, or even landfills that were not properly removed. They may have cleared out woods to develop the lot where your concrete sits, swamp grounds, or even quicksand. What is underneath your concrete, in most cases, will determine the success of a lift.
When it comes to decomposing organic fill, it may take several decades after the concrete was poured to start noticing movement or settlement. Once you start noticing settlement, it may take several more decades before the settlement stops. If you’re dealing with decomposing organic material, swamplike soils, or erosion issues underneath your concrete, you’re in the “May Never Stop Sinking” category.
Concrete on a sloped surface, or on or next to a hill
Concrete on or next to a hill or sloped surface is always going to be more problematic than concrete on flat ground. Most of the concrete that I have seen, no matter how well the ground was prepared, will eventually start sliding and coming apart at the seams as the ground moves. To help prevent the problem, customers will need to spend the extra time and money installing retaining walls and structural footings on the lower side of the slabs to help reduce the risks of slab settlement or sliding. If you have concrete poured on a sloped surface or on or next to a hill, you’re in the “May Never Stop Sinking” category.
Tree roots may have caused by concrete to become uneven
We receive calls almost daily about sidewalks that have become uneven due to tree roots. Quite simply, if tree roots are involved and the roots have not been cut, your concrete will continue to move. There is no “Never” or “Maybe” on this one; your concrete is certain to move if trees are involved. When we can, we try and advise our customers that lifting, grinding or replacing the concrete is only temporary unless the roots of the trees are no longer growing.
In some cases, the customer will tell us that the tree has already been cut down and would like to have the concrete fixed. In this case, the concrete would fall into the category of “Maybe Never Sink.” This would depend on how old the concrete is. If it is a newer slab, 20 years old or less, the roots will eventually start to decompose causing the slab to sink, but if the slab is older than 20 years, it may be time to replace the concrete before the old roots become a problem.
Depending on how bad the trees have affected the concrete will also determine the likelihood of having it fixed. Shaving or grinding down the offsets, in many cases, becomes the only option in lieu of having it all replaced.
What is being used to raise my concrete?
The two most recognized materials used to lift concrete is a slurry mixture of concrete known as Concrete Leveling, and the other material used is a foam product known as Polyleveling. Each of these methods have certain advantages and both are used to permanently raise slabs. If the contractor you hire uses one of these products, your chances of the concrete “Never Sinking” definitely increases.
Materials that may not be as effective, and have a higher probability of failing are: mud, clay, sand, non-compacted gravel, or shims such as blocks, plastic spacers or pieces of wood.
Contractors that offer these types of products would be Mudjacking Companies, Handyman Services, or DIY ideas you can research online. I’m not saying these other materials will not work, however, there is a higher probability of these materials failing. This would put your concrete in the, “May Never Stop Sinking” category.
Who is lifting my concrete?
Not all concrete lifting technicians have the same skill level, as with any trade. A properly trained and experienced foreman can go a very long way in reducing the likelihood of having to go back and redo the job. It never hurts to ask your contractor, “How long has the technician who will be lifting my concrete been doing this?” From my experience, any technician who has not spent at least one year in the field working with another experienced foreman will have major learning pains. I hope for your sake that they wouldn’t have to learn on your concrete!
Historically speaking, if you’re one of the 10,000+ customers who has had B-Level raise their concrete, your odds of being in the “Never Sink Again” category is about 93-96%. All of our technicians have had the proper training and the time spent with an experienced foreman before venturing out on their own.