SmartJacks™ tackle uneven floors in Bauxite, AR
Challenge
Client originally called Redeemers Group, because he had sinking and uneven floors on the interior of the house. Uneven floors are rarely caused by problems with the floor system itself. Instead, it's often a settling or shifting foundation issue that has impacted the floor system. Floor beams and joists are made from wood that will usually bend or flex rather than crack or break. The same can't be said for masonry foundations. When soil issues cause a foundation to break, the floors above usually bend.
Upon inspection of this house by System Design Specialist Wyatt Burford, it was found that at some point, concrete blocks were piled up under the underpinning in an attempt to stabilize the house from further sinking (see pictures). The problem with this approach is that the earth will continue to give way. Therefore, the floors were still sinking, and eventually the blocks would have fallen altogether.
Solution
A common (BUT FLAWED) approach to this problem is to buy some jacks from a local retailer, put them where the pillars were, and attempt to jack up the floor. The same problem exists here as it did with the previously mentioned approach of piling concrete blocks. Temporarily it would lift the floors, but, the earth will still give way causing it to sink like the original footing. You wouldn't have a permanent solution.
The Redeemers Group approach: Our production team began by digging 2x2 ft holes in the earth where our SmartJacks™ would later be installed (see pictures). Why only a 2 foot cube? Wouldn't it be better if be go deeper? No... Here's how the engineering works: at a depth twice the bearing width, bearing stresses dissipate to approximately 10% of those at the bearing surface. What?! In other words, the SmartJack™ pre-cast concrete base is 12" wide. This is the bearing width. Two times 12" is 24" or 2 feet. So, at the bottom of the 2 ft hole, the pressure that was being exerted at the pre-cast base is reduced down to only 10% of what it was. Even if the soil at the bottom of the excavated hole isn't all that strong, you can be assured that the "Bulb of Significant Stress Influence" (see photos) has already been distributed within the crushed stone footing. Any system that does not address this will not be a long-term solution.
They then fill the space with gravel and pack it in. The SmartJack™ is then placed on top of the packed gravel, giving it a much sturdier place to work from then directly on the earth. The weight is therefore distributed through the gravel instead of through the earth/mud. It can hold substantially more, and won't give way later on. (See pictures). More detailed info:
More about the SmartJack™ Stabilizer system: SmartJacks™ are steel support systems used to stabilize and level the girders and floor joists in a crawl space. The heavy-duty system has been laboratory tested to support loads of more than 60,000 lbs., making it the ideal system to stabilize your sagging floor, any walls sitting on top of that floor, and additional loads from the home. How does it work? To address weak foundation soils, a 2' cube of soil is excavated at each SmartJack™ location. The hole is then filled with either concrete or engineered fill that consists of tightly compacted crushed stone. Next, a high strength, galvanized steel column is cut to the appropriate height for your crawl space. The steel column and components are assembled and connected to the girder, and the SmartJack™ system is tightened into place. The girder and the floor joists are immediately stabilized, and lifting the above floors and walls back to level can be attempted.
When to use the SmartJack™ system: SmartJacks™ should be used when you want to accomplish the following:
- Best opportunity to lift the above floors and walls back to their original position
-Engineered footing transfers the load beyond the troubled soils
-Can be installed in conjunction with crawl space liner
-restores property value
Redeemers Group LLC of Tennessee, Mississippi and Arkansas is your local certified Foundation Supportworks™ (FSI) contractor. Learn more about the Foundation Supportworks™ network here: https://www.redeemersgroup.com/foundation-repair/about-foundation-supportworks.html
Project Summary
System Design Specialist: Wyatt Burford
Production Manager: Philip King
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