The structure of a home does not lend itself to flexing and movement caused by uneven foundation support. The roof, walls, floors, windows, doors all perform best and create the least amount of problems when they are not stressed or tensioned by a moving foundation. Knowing the signs caused by a shifting, heaving foundation or one that is not level, will enable you to determine whether you have foundation problems or just cosmetic problems caused by minor seasonal expansion and contraction.
Fundamentals of Foundation Support
Homes in the Dallas/Fort Worth area often experience foundation problems. The nature of the soil and substrate in this area and the extremes of heat and cold and wet and dry are particularly hard on foundations.
Foundation problems result when pressures increase or support decreases (often caused by environmental factors) which cause foundations to shift or cease to be level. Foundation problems range from hairline cracking that is difficult to reliably attribute to foundation movement, to severe drywall and brick veneer cracking accompanied by separation of the wood frame.
Signs of Damage May Not Indicate a Need for Repair
Some cosmetic problems that are not caused by problems in the foundation are similar to problems that are in fact caused by problems in the foundation. That sounds confusing so let me state it another way and give you an example. Problems that may look like they were caused by foundation problems may actually not indicate that you have foundation problems.
For example, a hairline crack in a joint of an exterior brick facade that is not growing and which is not an indication of a foundation problem may have been caused by seasonal expansion and contraction or may have been simply caused by the drying of the mortar. Furthermore slight foundation movement may have caused problems but are best not repaired by foundation repair but can be cosmetically repaired with mortar or sealant.
Signs of Damage that Indicate a Need for Structural Repair
Inspecting a foundation consists generally in looking for areas where unevenly supported loads have resulted in changes to the structure like cracks, bowing, buckling, heaving and other distortions. Analyzing why these distortions occurred and their current status, enables the inspector to determine the best course of action to undertake to remedy foundation problems. Generally speaking a structural repair is indicated when safety issues are of a concern, the problem cannot be repaired with non-structural remediation (sloping of the ground, amelioration of drastic changes in substrate moisture, addition of gutters and drains, removal of large plants next to the home), the problems are growing, the damage is severe and the likelihood that the situation is active, i.e., it is an ongoing problem that will cause more damage.
Interpreting Types of Cracking
A crack on one side of the wall of the foundation that has a similar type crack on an opposite wall can indicate a large problem causing these mirrored cracks. Vertical and 45 degree cracking is usually caused by settlement and heaving. Horizontal cracking is commonly caused by side pressure on the foundation, such as lateral pressure.
Cracks that go entirely through the foundation are worse than those that don’t. Cracks with large gaps indicate more movement than cracks with thin gaps however gaps can cycle between growing and shrinking depending on conditions.
Small hair-line cracks that do not go through the foundation wall are often common and may not be anything to worry about; they may have been caused by shrinkage of the concrete or mortar joints. Surface cracks that do not go entirely through the wall and with no signs of displacement are not normally indications of a structural defect. Isolated vertical cracks that do not extend to the lower edge of the foundation wall are usually shrinkage cracks. They are caused by the concrete shrinking during curing.
Old cracks will have dust, dirt, paint and insect parts in the crack. If the foundation is not stable, you will have what is sometimes referred to as an active crack which changes in configuration over time.
Cracks in interior walls and ceilings can also be caused by normal seasonal house expansion. Wall cracking alone without other evidence of foundation problems is caused by this seasonal expansion and contraction.
Large cracks 3/8″ wide or wider should be carefully examined and a specialist in foundations should be consulted.
The solid foundation resists lateral pressure from soil on the outside of the basement or crawl space. If the foundation does not provide enough lateral support, the walls will deflect inward and create horizontal cracking. Some of the causes of insufficient lateral support thin walls and insufficient re-bar reinforcement. Also, horizontal cracking and loss of structural integrity can occur if at the time the home was built, backfilling was done before the foundation is properly cured or if large objects impacted the foundation at the time of backfilling.
Vertical movement under the foundation is known as heaving and causes what are known as “heaving cracks” on foundation walls. These cracks are usually narrower at the bottom than the top. Heaving under brick, block or stone foundations causes “step cracking” These cracks normally follow the path of least resistance which would be mortar materials between the bricks, blocks or stone.
Expansive soils, often found in and around Dallas and Tarrant Counties, Expansive soils increase in size when they absorb water, causing heaving cracks. The sudden addition of water such as from a downpour or flooding inside the home can drastically increase the volume of the soil and cause serious heaving problems. Then when expansive soil dries, shrinkage occurs leaving behind unsupported structures.
Preventing heaving is accomplished by preventing excessive water from affecting the soil that contacts the foundation and shrinkage is prevented by preventing excessive drying of the foundation. Proper grading around the home aides in preventing these two conditions.
Settling of the soil under the foundation is also a cause of settlement cracks in the foundation walls. Cracks caused by settling are narrower at the top as compared to the bottom.
Doors and windows that are stuck and misalignment (gaps)
Foundation settlement can cause doors and windows to be difficult to open and close. In addition to opening and closing doors and windows, look for gaps that are larger on one side than the other. This can indicate settling and help determine where the settling is occurring.
Sloping or tilting floors.
Use a level to determine if the floor is level. Floor elevations should be recorded for future reference in the inspection.
Unless the sloping is substantial or extensive remodeling is planned, the best repair would be to stabilize the foundation. Extensive re-leveling in an older home may cause more than expected damage to the interior walls, ceilings, doors, windows and cabinetry. If the home has been stabilized and future movement is unlikely, slightly uneven floors are acceptable. Most people will not notice sloping less than 1/8″ slope per foot. 3/16″slope per foot is noticeable to most people.
Power Jack Foundation Repair
If you are planning to sell your home, a home inspection can give you the opportunity to make repairs that will put the house in better selling condition. Power Jack Foundation Repair can perform your pre-listing home inspection, so get a jump start on selling your home by calling Power Jack Foundation Repair to learn more about having your home inspected before listing it on the market. You’ll be glad that you did!
Power Jack Foundation Repair also has extensive experience with repairing all the damages that are caused by problematic foundations. It has an excellent reputation and not only directs and monitors the work done and again, stands behind its work with its True Lifetime Transferable Warranty that covers the repairs for the life of the structure. It is fully transferable to future homeowners at no charge. The field representative who inspects your home will be happy to show you a copy of the warranty certificate or contact our offices.