Why concrete sinks

Posted Mar 31, 2021 in Concrete Raising

Service concrete raising

Sink­ing con­crete – you’ll come across it in the form of uneven, cracked, or sunken con­crete slabs. And it doesn’t hap­pen with­out cause. In fact, slab set­tle­ment is to blame when it comes to your uneven con­crete slabs. What is slab set­tle­ment you ask? Well, slab set­tle­ment refers to the move­ment a con­crete slab expe­ri­ences when the soil below can no longer sup­port the weight of it.

Sink­ing con­crete prob­lems and causes:

When it comes to slab set­tle­ment, soil changes under­neath your con­crete slab is the cul­prit. While there are many rea­sons why the soil may change under­neath your con­crete slab, there are three main causes.

  1. Soil Washout under the Con­crete Slab
  2. Poor­ly Com­pact­ed Fill Soil
  3. Soil Mois­ture Con­tent Changes

Soil washout under the con­crete slab

Water caused by plumb­ing leaks, ero­sion, large rains, etc. will find its way under­neath your con­crete slab. As this water moves under­neath your con­crete slab, it can wash away the soil that’s sup­port­ing the weight of the con­crete. As this process re-occurs over time, the amount of soil present under­neath the con­crete slab will dimin­ish and your con­crete slab will begin to sink because there is not enough soil to sup­port the weight of the slab.

Poor­ly com­pact­ed fill soil

Dur­ing the con­struc­tion of a dri­ve­way, patio, side­walk or home, the soil is most often spread out or moved around to achieve the desired grade lev­el. If a new con­crete slab is poured right on top of this loose­ly com­pact­ed soil then slab set­tle­ment is more like­ly to occur. As the fill soil under­neath the slab com­press­es and set­tles, emp­ty space is cre­at­ed under the con­crete. So, with noth­ing to sup­port it, the con­crete breaks, cracks, and set­tles into the emp­ty space.

Soil mois­ture con­tent changes

Cycles of wet and dry have a direct effect on the soil under­neath the con­crete slab. When soil types like clay get wet, it holds onto the water and expands in size. When the soil becomes dry due to occur­rences such as drought con­di­tions or tree roots draw­ing valu­able soil mois­ture, soil begins to shrink, cre­at­ing emp­ty space under the slab, result­ing in uneven and cracked concrete.

Learn how we can lev­el your con­crete slab

Fam­i­ly Water­proof­ing Solu­tions has the exper­tise to eval­u­ate your uneven, cracked con­crete slabs, allow­ing you to quick­ly enjoy using those areas around your home. If you would like to learn more about con­crete lev­el­ing ser­vices, con­tact us today for your no-oblig­a­tion free esti­mate.

What our customers say

  • We con­tract­ed Fam­i­ly Water­proof­ing Solu­tions for exte­ri­or wall seal­ing and foun­da­tion crack repair ser­vices. Ken was very thor­ough in explain­ing the work that would be done, and his crew did a great job. This busi­ness was a plea­sure to work with.

    Stacie T.
  • Work­man­ship and ser­vice were excel­lent. Would rec­om­mend with­out reservation.

  • You and your crew did a great job in our base­ment and crawl­space. You went the extra mile to insure that all of our water seep­age prob­lems are over. We would rec­om­mend you high­ly to oth­er peo­ple. Your qual­i­ty and time­ly work out­match­es all the others.