Underpinning & Lowering Your Basement

If you have a basement with a low ceiling you can create a proper living space by lowering the basement floor.

A Big Job With Many Advantages

Underpinning is the process where your basement floor is dug out and lowered so that more living space can be created.

While it is a big job, underpinning has a variety of advantages:

  • Increased living space
  • Higher property value
  • Able to install new, larger windows
  • More daylight into the home
  • Able to address foundation issues during the process
  • Able to evaluate and install new waterproofing elements

Underpinning will Restore Your Foundation

Damaged foundations can benefit from underpinning because the excavation and new concrete will fix previous settlement issues. In other words, Underpinning stabilizes the overall foundation. For such an extensive task, trust only a waterproofing and foundation repair company with years of experience. Underpinning has great benefits, but it must be done right the first time to avoid future structural or water issues.

Professional Tip: Underpinning is a large project and you must make sure to select a company that is fully insured and can draw on years of experience to create architectural drawings and plans, as well as obtain the necessary permits for excavation and underpinning. Stay Dry is one of the companies that can do it all.

Underpinning Methods

The overall goal is to support the weight of the building structure with concrete. After structural supports are in place, the weak soil is dug out and excavated followed by a mass pour of concrete. This is a an affordable method and it is also easier to perform providing the circumstances allow for it.

Professional Tip:  A polyurethane mix can also be used rather than concrete. It can also raise the foundation higher, but this material will substantially raise the cost of the underpinning project.

Beam and Base Underpinning

This method involves a concrete base but also the use of concrete beams that will transfer the weight load to the mass of concrete that was poured. This method is more complicated and depends on the surrounding ground and the size of the concrete base. The beam will vary in size depending on the building and the load that needs to be carried.


This method of foundation stabilization involves drilling holes under the foundation, or through the concrete, and then pumping a special concrete mix underneath, aiming to eliminate any problems stemming from foundation settling.

A mortar-based mix is usually pumped under the foundation, which then cures and provides stability. Empty spaces are filled with a solid mass, once cured, to support the foundation. Mudjacking is not always the best option and so have an experienced professional assess your needs prior to selecting this option.

Why Is My Basement Settling?

You may be wondering why you need foundation repair work in the first place. What is actually causing the foundation settlement you are observing in your home?

Soil Issues
Poor drainage can cause surrounding soils to hold too much water, compromising their ability to hold weight, causing shifting, and leading to a settling in the foundation, or even worse, cracks.

Water Issues
Water damage from outside entry, or from plumbing issues, can cause foundation damage over time and lead to cracks, heaving or mold.

Temperature changes
Frost damage, moisture imbalance and temperature changes can wreak havoc on a home, especially if the surrounding soil is caused to move away from the home or lose its compaction.

Nearby construction or seismic activity can damage your foundation and cause cracks or settling depending on the nature of the work and the proximity.