Floors sag and suffer from differential settlement due in the main to some very simple processes. Water is the most common contributing or causal factor.

Since your house was built, you and previous owners have been raking up leaves and debris, starting at the perimeter of the house. Over the years, little by little, dirt is raked away from the house, along with the other material. As you take a little soil from here and leave it there, a compounding effect becomes evident. A valley next to the foundation has been created, and a little hill has been formed a short distance away. This produces a trap for rain and gardening waters to puddle and pond right next to your foundation.

Wet soil has reduced bearing capacity. As winds blow against your roof and the side of your house, the wind forces will shudder down the walls to the foundation. Pressures pound, shake, and drive against the foundation causing it to settle a little into the wet soils.

Wind forces, sonic booms, and small earthquakes will cause your house to shudder. Added to and combined with the number of times in fifty or so years the soil has been wet with standing water around your foundation, resulting in varying degrees of settlement and sagging floors you might be experiencing.

You have seen homes where a marble, placed on the floor, will quickly roll to the outside walls. The under floor supports – piers – usually rest in dry soil conditions and will not sink along with the perimeter foundation. The result is a domed floor surface, wreaking havoc with doorframes and window margins. In short, the doors become difficult to close, and cracks in the finished surfaces begin to show up more and more often.

FLOOR PLANE ADJUSTMENTS AND HYDRAULIC LIFTING

Due to the externally applied stress caused by differential movement in the support members, wood members of the floor have bowed into an arc. In this condition, the wood is in tension and most often in tight contact with those supports. 

During the lifting process, the stress is relieved at the ends of the wood, but the member retains all or part of the warped or distorted state. The floor surfaces at end points may be level after the lifting operation, but the mid-section is above the desired plane. From the standpoint of support repair, nothing further can be done to improve the situation.

The wood fibers are not as fresh as they once were, nor are they under the same stress factors to relax the now-crowned set. To add further complication to the floor-lifting endeavor, there is an element of some cracking of finished wall surfaces along with changes in door and window margins. The solution lies between a compromise and the cost-prohibitive steps of total replacement.

Few of us realize that many structures are not initially constructed perfectly straight and true. Any attempt to correct an inherent problem will result in the creation of new distress. For this reason the structure support system is normally raised to a proper load-bearing position.

Even then, some compromise is often required to equate the degree of adjustment with practical job conditions. For example, if a lifting operation intending to close a 1/4" crack produces an offsetting 1/2" crack, nothing has been gained and a compromise must be made. Further, warped joists and floorboards are antagonistic to floor straightening.

In order to achieve optimum results, we would want you to be aware of changes as they occur in the entire lifting and blending operation. Because of the above-related possible effects, we would request your presence and input during the critical phases of this procedure.

We suggest preventative maintenance procedures such as rain gutters, proper drainage patterns or drainage systems, and other measures to halt or diminish settlement progression. Remember once something starts to fail, the rate of failure accelerates. Like a rock in a mudslide, it just keeps getting faster, until...disaster.