Answers to Frequenly Asked Questions

We have provided a dictionary file to help define some of the technical and construction related terms in our reports in our Dictionary File.

These are some of the most commonly ask questions we receive. Most of our work is performed in the Houston area, and all of our work is performed in South Texas. Our answers when region specific are only intended to address these specific areas.

  1. What are pitfalls to avoid when maintaining a foundation on expansive soil?
  2. Is my slab cracked?
  3. When should I call a foundation repair company?
  4. Are all foundation repair companies alike?
  5. If the house is built right, can I still have foundation problems in the future?
  6. How does the cost of maintaining a foundation compare to the cost of repairing it?
  7. Is the soil in some areas of Houston worse than others?
  8. What are the effects of subsidence in some areas of Houston?
  9. What are the effects of fault lines in some areas of Houston?
  10. Do all areas in the U. S. have the same problem with expansive soils?
  11. Is one kind of foundation worse than others?
  12. Can I qualify for an FHA loan if there's a crack in the foundation?
  13. Should I be concerned about hairline cracks under my carpeting?
  14. Will an addition to the house have more foundation problems?
  15. What's the best/worst shapes for a house?
  16. Is the resale value of a house less if it has had the foundation repaired?
  17. Can a foundation experience damage from improper repair?
  18. Does a repaired foundation still need maintaining?
  19. How long does a foundation repair job last?
  20. Can a foundation watering program be implemented instead of releveling with piers?

  21. If you don't see the answer to your question here, please don't hesitate to call us.  You may also submit your questions via the E-mail.


What are pitfalls to avoid when maintaining a foundation on expansive soil?
  1. Never allow the soil around and below the house to become dry during extended dry periods. Highly expansive clay soil will shrink in volume and allow the foundation to settle downward. The foundation will experience "differential settlement" which is detrimental to the building structure if the soil at the perimeter foundation dries before the soil under the floors. The soil usually dries slowly under the floors because its moisture is trapped by the floor of the building.
  2. Never apply water directly into the gap that opens between the concrete slab and the soil during extended dry periods. Water flowing under the concrete grade beams that make up the support the building will dissolve the clay in the soil below the beams and carry it away into the cracks that form in the yard as the soil dries. Soil carried away in this manner is lost and so is the height that it contributed to the elevation of the foundation.
  3. Never allow the surface of the soil immediately adjacent to a concrete slab or grade beam or the piers that support a building to acquire a slope toward the building. The surface of the soil should be carefully graded to slope away from the building at a rate of more than 1" per foot for a distance of three to four feet. An example of creating undesirable perimeter drainage is where a dog digs a cooling pit at the edge of a foundation.
  4. Never repair damaged areas inside your house until you have found the cause. You should not cover up the symptoms of foundation settlement until you have corrected the problem. This will save both time and money on repeated repairs.

  • Is my slab cracked?

    Most concrete slab foundations acquire cracks during curing of the concrete or with heaving of highly expansive clay below the slab as it acquires moisture after construction is completed. Many of these types of cracks have little or no effect on the performance of the foundation. The term "Cracked Slab" is a colloquialism used by real estate agents or persons familiar with abnormal foundation differential settlement. Cracks usually develop in the floors and grade beams of buildings having an abnormal degree of differential settlement. The cracks in concrete are normal and could be a symptom of differential settlement and not the problem.


    When should I call a foundation repair company?

    It would be advisable to contact a foundation repair company after the need for repair has been determined by a non­biased professional (one who does not sell foundation repairs), who has the training and experience necessary to determine when the differential settlement has become severe enough to warrant repair of the foundation. Some homeowners may decide to have their foundation releveled if the slope of the floors has become uncomfortable, even though the damage to the structure may be relatively minor.


    Are all foundation repair companies alike?

    Foundation repair companies are not alike. Some management persons have more experience than others and some have different opinions as to the type work that is necessary to insure the foundation remains level. Some foundation repair companies may provide a much better warranty than others. Different foundation companies may also use different systems for re-leveling such as drilled, belled bottom footings, pressed pile piers, and/or watering systems.


    If the house is built right, can I still have foundation problems in the future?

    It has often been my experience that houses with foundations properly designed and constructed in accordance with recognized procedures still develop evidence and/or consequences of differential foundation settlement. A house constructed on well compacted, non expansive fill, with large grade beams and subterranean piers have the least likelihood of foundation movement becoming evident. Even these houses should be constructed with the foundation not attached to the tops of the piers. The foundation slab should be allowed to float up and off the piers if the soil expands or contracts. For best performance of most foundations, it is recommended that the recommendations provided in our Foundation Care Document be followed for foundations resting on expansive clay soil.


    How does the cost of maintaining a foundation compare to the cost of repairing it?

    The cost of maintaining a foundation is usually much less than the cost of repair. It certainly has less effect on one's normal life style than that noted while the foundation is being repaired. The cost of foundation maintenance is usually less than the yearly interest that would be due on money borrowed to make foundation repairs.


    Is the soil in some areas of Houston worse than others?

    Some locations in the Houston area have soil that is more expansive than others. The more expansive the soil, the more it changes volume with change in moisture content, and the greater the effect it can have on the performance of a buildings foundation. There are some locations in the Houston area where the soil is a sandy loam which has little change in volume with change in moisture content.


    What are the effects of subsidence in some areas of Houston?

    Subsidence usually refers to sinking of the soil surface in a large area. Unless there is a fault where the soil shifts vertically, the subsidence of land usually does not adversely affect the performance of a building's foundation. In some cases, subsidence of the land results in tilting of a structure because the surface of the land that has experienced subsidence slopes toward the lowest point of the subsidence. Uniform tilting of a structure does not adversely affect its integrity unless the tilt becomes very pronounced (a slope of greater than .25 inches per foot would begin to have an adverse effect on the acceptability of a structure for comfortable habitation).


    What are the effects of fault lines in some areas of Houston?

    Fault lines of the type found throughout the Houston area have a very detrimental effect on the performance of a building's foundation if the building is located directly across the fault. A building resting across a fault line cannot be leveled and remain level. A building resting on a fault must be periodically releveled to maintain its structural integrity.


    Do all areas in the U. S. have the same problem with expansive soils?

    Although I am not familiar with all areas in the U. S., there are undoubtedly areas where the land is not expansive and there is little or no problem with foundation differential settlement. Local areas, like most of Galveston Island, are primarily sand which does not expand and contract with change in moisture content. If the land does not shrink or expand, a building resting on it is likely to experience little or no movement.


    Is one kind of foundation worse than others?

    No one type of a conventional foundation is better or worse than another if the foundation is properly designed and constructed. A block, pier, or pier and beam foundation is usually much easier to return to a level condition if it becomes unlevel. If the foundation is properly designed and maintained according to local requirements, most any foundation will perform in a satisfactory manner.


    Can I qualify for an FHA loan if there's a crack in the foundation?
     

    If the foundation of a house has experienced abnormal differential settlement that is adversely affecting the performance of the structure, the HUD agency will not guarantee a loan for the property unless it has been repaired in accordance with a design developed by a qualified Professional Engineer who will oversee the implementation of the repair. If there are small cracks in the concrete slab that are not adversely affecting the building's structural performance and there is no evidence of abnormal conditions that could result in additional differential settlement of a particular building's foundation, the HUD agency will guarantee a loan with an acceptable engineering report. See description of cracked slabs above.


    Should I be concerned about hairline cracks under my carpeting?

    Hairline cracks in a concrete slab, even those found below carpeting are not necessarily a measure of foundation performance. If there are floor cracks and abnormal cracks and separations in the superstructure of a building, then there is cause for concern that should be further evaluated by a qualified professional. Cracks typical of those often found when carpeting is removed can be found in the concrete floor of most garages. See description of cracked slabs above


    Will an addition to the house have more foundation problems?

    The addition of rooms to one or more of the sides of a house will not have an adverse effect on the performance of either the addition or the original structure; however, the two separate foundations will be prone to differential settlement with respect to each other. The addition of rooms as a second, third, or higher floor of a structure may adversely affect the performance of the original building's foundation. If it is desired that an additional floor be added, tests and inspections should be made to evaluate the foundation, the soil, and the structure of the original building before continuing with construction.


    What's the best/worst shapes for a house?

    The best shape for a house resting on highly expansive clay soil is square, round, or rectangular. U, C, H, L, and other irregular shapes usually exhibit evidence of foundation movement more readily than other types of construction. The expansion and contraction of expansive soil at the inside of the U, C, H, or L shaped houses tend to force the protruding wings apart, causing damage to the superstructure and the foundation.


    Is the resale value of a house less if it has had the foundation repaired?

    The resale value of a house having need for foundation repair can be increased significantly by having the foundation releveled. The value of a house which has had the foundation repaired as compared to a similar house which has not had the foundation repaired and does not need repair is about the same. It is pointed out that some people will not purchase a house that has been releveled.


    Can a foundation experience damage from improper repair?

    Yes, an unqualified foundation repair contractor can cause additional damage to the structure and foundation while releveling the foundation.


    Does a repaired foundation still need maintaining?

    For best performance, a repaired foundation should be maintained in much the same way as the foundation of a house resting on expansive clay soil which has not been repaired. See our Foundation Care Document


    How long does a foundation repair job last?

    Properly installed piers should last for the life of the building. The piers should ensure less movement than the building would have experienced if the piers were not installed. For best performance, a repaired foundation should be maintained in much the same way as the foundation of a house resting on expansive clay soil which has not been repaired. See our Foundation Care Document


    Can a foundation watering program be implemented instead of releveling by putting in piers?

    A foundation watering program and/or system can, in many instances, be implemented rather than installing piers to relevel a foundation. If the house has been out of level for an extended period of time (several years), it is probable that watering will not cause the foundation to become more level. If the differential settlement has been caused by washing away of soil or by movement of a fault, then watering of the soil will have little or no effect. The results of a watering program is usually much slower than installation of piers.