Stabilizing a Crawl Space Foundation in McKenny, VA
Challenge
This homeowner in McKenney, Virginia reported that his kitchen floor was sagging and asked us to inspect the crawl space and foundation. We sent out one of our experienced home performance advisors to evaluate these concerns and give the homeowner a free estimate.
Upon inspection, we discovered that the floor joists and the support beams, otherwise known as girders, were indeed sagging. When the columns are too spaced apart, the beam can become too overloaded and begins to drop. When the beam or girder begins to sag drop, so does the floor above it. Excess moisture and wood root can also cause beams and joists to weaken. When the relative humidity in the crawl space is high, moisture is absorbed by the wood, which over time will begin to rot and get moldy, weakening it.
Weak foundation soils can also cause issues for these support beams. Soft soil can cause the columns in the crawl space to sink or settle over time, creating a gap between the support beams girder and the floor joists. The crawl space piers will begin to sink, loosening the support of the beams with the subfloor. It is a chain reaction that eventually leads to the sagging of the floors above.
Solution
We proposed many different solutions that would help protect and rectify the issues found within this homeowner’s crawl space. First, we would want to replace the rotted/damaged support beam with a steel I-beam, supported by the piers. After that, we would add SmarkJacks to support the new girder. After the repairs are done, we would move on to sealing the crawl space. First, we would advise attending to the mold and mildew with Mold-X2 or Shockwave. Then we suggest having a CleanSpace vapor barrier installed to help protect the crawl from the earth’s moisture. The next step would be to cover all open vents on the foundation walls and add a closed-cell spray foam or Foamax foam board to insulate the crawl space walls which will help in the defense from outside air and moisture influence. Then, we proposed adding a SaniDry Sedona dehumidifier and Little Giant condensation pump to help control the relative humidity.
The homeowner decided to focus their attention on the foundation repairs and replacements first. The first step we took was replacing the support beam with a steel I-beam girder. The girder supports the floor joists and subfloor above while being held up by the piers. With the piers sinking and the girders sagging and cracking, we needed to replace the support system for the girders as well.
We installed SmartJacks to hold the weight of the girders and stabilize lift the above floors and walls back into their original position. SmartJacks can support up to 60,000 pounds and can help level girders and floor joists within the crawl space. We excavated a cube of soil at every SmartJack location and filled each hole with a footer of concrete and tightly compacted crushed stone. A strong, galvanized steel column was cut to support the height of the crawl space and then assembled with the SmartJack components and connected to the girder. The original piers that haven sunken into the weak soils will no longer be of use, so the SmartJacks will be positioned closer together, distributing the weight much more evenly. The floors above will be more level and stable now, and the floor joists will no longer sag.
