Saggings Floors and How They Signal Crawl Space Damage

Sagging floors can be a safety hazard and over time become a serious problem if it is not fixed properly. Few support beams placed throughout the crawl space or spaced incorrectly can cause the beams to weaken over time and cause the flooring above to start to sag down which creates an unsafe environment above.

To fix your sagging floors and keep your home’s structure intact, contact MidAmerica Basement Systems.


A floor joist shows signs of compression due to the heavy weight of the home—and too few crawl space supports.

Inadequate crawl space support leads to sinking floors, uneven floors, and damage to your structure.

Causes & Repair Solutions For Sinking, Sagging Crawl Spaces

Crawl space jack posts provide a fast, permanent, warrantied solution to this problem. They're a great option for homeowners investing in home repairs.

The Problem:

Your crawl space is experiencing structural problems that are causing it to sink or sag in the middle.

What's Happening:

Crawl spaces experience structural sagging for these three primary reasons:

  • Support columns spaced too far apart
  • Rot-weakened joists, girders, posts
  • Columns settling due to weak soil/poor footings

Telltale Signs:

  • Tilting or sinking crawl space supports
  • Moist, rotting wood
  • Sagging, sloping, or uneven floors upstairs
  • Cracks in interior drywall
  • Door & window frames skewed and/or unlevel

How to Fix It:

Additional crawl space supports should be installed to ensure that your structure is properly stabilized. Mold and rot should also be addressed by installing a crawl space liner and removing excess moisture from the crawl space.

We can fix your sagging crawl space! Call us at 563-202-1650 for a free crawl space repair quote today!

We serve Davenport, Peoria, Waterloo, Iowa City, and many nearby areas in Illinois and Iowa.


A moldy, unsupported girder sinks under the weight of a home due to an improperly installed crawl space support. If not addressed, could mean significant damage to the home.

Advantages To Our System:

At MidAmerica Basement Systems, we recommend installing the SmartJack® System, which uses adjustable heavy duty steel crawl space jack posts. These posts install quickly in a home and provide the best solution for restoring stability to your structure.

The SmartJack® system can be installed in tight conditions, usually in less than a day. Made with galvanized steel for corrosion resistance, it can support vertical loads exceeding 60,000 lbs.

The adjustable design of our crawl space jack system means that sagging floors can not only be stabilized; they can also be restored their original position in many cases.

To address the issue of poor supporting soils, each crawl space jack distributes the weight of the home through a precast concrete footing and a base of engineered fill material.

The SmartJack® is the only solution that addresses problem soils during crawl space restabilization!

Installing the SmartJack®

Installing the SmartJack® is a fast process that will not disrupt your home or landscaping. During our crawl space repair, your installers will follow these five steps:

What NOT To Do

Here are three fixes that we at MidAmerica Basement Systems do NOT recommend:

Concrete Columns

Crawl space girders or beams are sometimes supported by columns made from concrete blocks. The blocks are typically stacked on a concrete footing and held together with mortar.

Once the column has been built and the mortar has cured, the extra space between the uppermost block and the floor girder above is filled with wooden spacers or shims.

Because of the wait for the concrete footing and mortar to cure, this is a very slow, time-consuming process.

Since the completed column isn't adjustable, additional shimming will be needed as the concrete column settles or the wood girder shrinks.

Additional Shimming

This is a cheap fix solution for repairing a girder and floor that have sagged because of settled concrete columns. Temporary jacks are used to lift the girder, and wooden shims are pushed between the existing column and the floor girder. The jacks are then removed.

This is a short-term fix only—the concrete columns will continue to settle, requiring additional shimming and maintenance in the future.

Light-Duty Jack Posts

Skinny, light-duty jack posts are available at many hardware stores and home centers. This type of adjustable steel post is often installed on top of a concrete block that rests on the ground in the crawl space.

Unfortunately, these posts hold very little weight, have poor stability and are difficult to adjust. Also, they won't compensate for poor supporting soils in the crawl space. This is not the solution you need!

We're YOUR Crawl Space Structural Support Contractors!

If you'd like a permanent solution for your crawl space issues or any other foundation problem, we're ready to help you. We offer free crawl space structural repair quotes to homeowners in the Illinois and Iowa area. To schedule your free, on-site visit and written estimate, call 563-202-1650  or contact us today!

Our service area includes Cedar Rapids, Peoria, Waterloo, Davenport, and nearby areas such as Iowa City, Normal, Rock Island, Dubuque, Moline, East Peoria, Clinton.