Structural problems, such as sagging beams, settling columns, or fatigued floor joists, are all too common in a crawlspace. Settling columns in a crawl space are most commonly caused by weak supporting soils underneath that cannot stand up under the weight and pressure being transferred to them through the home. Over time, these weak soils will begin to shift and settle due to changes in density and moisture content. As this occurs, the columns and beams will begin to move out of position.
Sagging beams and floor joists are commonly caused by the improper spacing of the existing pier columns. By placing pier columns too far apart, beams can become overloaded, forcing them to bend and sag. This leads to sagging floors above, cracks in the walls, and a variety of other foundation issues.
Rebuilding the crawl space is not necessarily the best option for a crawl space repair; there are installations that can be done in a day or two's time that will both reinforce the structure and potentially return the floor to its original position. The following is a list of common crawl space structural repair options:
Concrete Columns and Additional Shimming
In some cases, concrete columns are constructed in the crawlspace to add solid, rigid support underneath the home. However, these columns are tine consuming to create, as a wait is necessary while the concrete cures. Because the columns are not adjustable, they will not return the structure to the original position. Additionally, non-adjustable columns will need to have additional shimming installed if the damage worsens.
Additional shimming is a temporary fix at best. Once installed, the space must continued to be shimmed and reshimmed, as the damages will recur. As with concrete columns, reshimming cannot lift floors and walls.
Crawl Space Jacks
Crawl space jacks are adjustable metal beams that are installed in a crawl space via portable support beams. To be installed, a hole is dug and a solid base of engineered fill is established underneath the crawl space jacks, and a pre-cast concrete base levels the beam at its base on the ground. A threaded metal rod is cut to the appropriate length, assembled, and mounted on the base. The system site is then tightened and adjusted to fit on the floor beams above.
Crawl Space Jacks can be installed in even cramped spaces without the mess of concrete or the need to wait it to cure. In addition, they provide immediate stabilization and results, and because they can be adjusted, they can be used to help move the floors and walls above to their original position.
These crawlspace jacks work by transferring the load of the home from the beams and supports downward into existing soils. They're stronger and better at bracing homes than concrete beams, and they're able to be installed as part of a crawl space encapsulation system. The installation usually can be completed within a day, making for the best all-around option.
Light-duty Jack Posts
Light-duty crawl space jack posts are designed as a cheaper alternative to the more rugged designs on the market. They have very limited load-bearing capacities and are difficult to adjust. They're often not installed with an engineered fill underneath, and as such, they depend on the same weak supporting soils that caused the crawlspace supports to fail in the first place. They're a better option than concrete columns, but ultimately they're not the best option for a crawl space.
Heavy-duty Jack Posts
Heavy-duty jack posts made with galvanized steel will prove to be the strongest, most corrosion-resistant solution for crawl space structural supports. These jack posts should be able to hold well upwards of 50,000 lbs of weight per brace and can be adjusted easily to restore the home's structure and property value. They use a base of engineered fill underneath for added support, and they install with no need for additional shimming later. This is easily the best option for crawl space repair.
Crawl space supports are best used in conjunction with a crawl space liner and the other components of a crawl space encapsulation system. Installing a vapor barrier and sealing the vents will preserve all wood support beams and structures, keeping them strong and ready to hold your house up for the long haul. Click to learn more about crawl space encapsulation!