Why Does Concrete Sink?

Why Does Outdoor Concrete Sink?

Void in concrete sidewalk

Soil washout can result in empty space beneath your concrete slab, unable to support it. This can lead to cracks and sinking over time.

Concrete is heavy! When the soils underneath a concrete slab are unable to support its weight, the slab will sink.

If part of the concrete slab is supported by soils and other sections are not, the unsupported pieces may crack away from the other section and result in unlevel concrete.

AFS Foundation & Waterproofing Specialists can inspect the condition of your concrete slab during an on-site estimate. Call us today to schedule a free quote in Montgomery, Birmingham, Mobile and surrounding areas.

Primary causes of sinking outdoor concrete

    1. Soil Shrinkage, Compaction & Settling

      A hoofprint in the mud, showing compacting soils

      Different types of soil have different load-bearing capacities. When a soil's load-bearing capacity is exceeded, the soil will compact and settle.

      It's also possible for the soil beneath a slab to settle and compact of its own accord. Soil that contains large amounts of clay and/or silt will shrink substantially when it gets dry.

      As the soil compacts underneath a concrete slab, the unsupported slab will sink as well, usually cracking in one or more spots.


  1. Washout Of Soils

    Water washing away mud and sediment in rainy weather.

    The soil that is underneath your driveway, patio, or concrete steps may not necessarily remain there to provide adequate support for the concrete element.

    As water moves underneath your concrete slabs, it can wash away the soil that's supporting the weight of the concrete. As this happens, it creates a void, or empty space, underneath. Over time, with nothing to support it, your concrete slab can begin to sink or cave in.

Want a permanent solution? Learn more about our PolyLevel® installation in Alabama

The good news is that you don't have to live with sunken concrete anymore! Check out our before and after photo gallery to illustrate what PolyLevel® concrete lifting can do for your property!

We would be happy to provide you a free evaluation and cost estimate in Huntsville, Tuscaloosa, Hoover, Madison, Decatur, Columbus, Auburn and other local areas.

Looking for a price? Get a no cost, no obligation free estimate.

our service area

We serve the following areas

Alabama
  • Bridgeport
  • Bryant
  • Dutton
  • Estillfork
  • Fackler
  • Flat Rock
  • Fort Payne
  • Gaylesville
  • Henagar
  • Higdon
  • Hollywood
  • Ider
  • Mentone
  • Pisgah
  • Rainsville
  • Stevenson
  • Sylvania
  • Valley Head
Georgia
  • Chickamauga
  • Cohutta
  • Crandall
  • Dalton
  • Flintstone
  • Fort Oglethorpe
  • La Fayette
  • Lookout Mountain
  • Lyerly
  • Menlo
  • Ringgold
  • Rising Fawn
  • Rock Spring
  • Rocky Face
  • Rossville
  • Sugar Valley
  • Summerville
  • Trenton
  • Trion
  • Tunnel Hill
  • Wildwood
Tennessee
  • Apison
  • Chattanooga
  • Guild
  • Harrison
  • Hixson
  • Ooltewah
  • Sequatchie
  • Signal Mountain
  • South Pittsburg
  • Whiteside
  • Whitwell
Our Locations:

AFS Foundation & Waterproofing Specialists
2415 Jordan Road
Huntsville, AL 35811
1-256-418-4540


AFS Foundation & Waterproofing Specialists
9079 U.S. 78
Leeds, AL 35094
1-205-386-8803


AFS Foundation & Waterproofing Specialists
25476 Friendship Rd
Daphne, AL 36526
1-251-299-2059


AFS Foundation & Waterproofing Specialists
214 Industrial Park Dr
Soddy Daisy, TN 37379
1-423-933-1626