Is it a Foundation Settlement or Heave?
Knowing the difference between the two problems will save you thousands of dollars. Many times you start to recognize the signs of heave or settlement in your home but often times do not know what they mean. Have you started to see cracks or sloping in the floors, cracks on the interior or exterior of your home, doors and windows are starting to get hard to open and close. As a homeowner, often times we recognize that these are problems but we do not realize why they are happening. Usually this can mean one of two things either the interior slab is heaving upward or the footings on the perimeter of the house are settling downward.
It can be very difficult to know the difference between the two, because they share many of the similar symptoms. A slab heaves in the interior of a home because moisture penetrates underneath the house and mixes with the clays, saturating those particles which in-turn causes them to swell. This typically will happen in the middle of the house because it is the area with the least amount of weight. In order to tell the difference between the a heave and a settlement. The first step we reccomend is for a floor level survey to be performed, which measures floor elevations. The data helps us understand what is happening with the interior floors.
With this data we are able to recognize patterns of highs and lows, which help in understanding what is happening with the your floors. For instance if you have low readings consistently around the perimeter of the house with high readings in the middle, you can logically assume that the area with higher readings has risen instead of the entire perimeter settling at the same rate. Settling occurs in sporadic movements and is not usually consistent around the perimeter.
Another way to determine heave is by the damage to the house. Is the damage more in the middle of the home or is it on the perimeter or outside walls? If there are more drywall cracks and damage to the inside walls and floors, with very little exterior damage, the chances are that the interior is moving. Typically in this case the slab is moving as opposed to the exterior footings. One thing that you might do is check the perimeter stem wall on the outside; stucco cracks for a variety of reasons and is typically not the best indicator of anything in particular. Cracks in the stem wall are more indicative of problems that may be occurring in the footing and point more to a settlement related issue. Once we have diagnosed between heave and settlement, the treatment can take two different courses.
If you have a heave situation on your hands, then measurements of the floors is essential because the only way of really knowing whether you were effective or not is to re-measure the floors at a later date. Usually the first line of action to re-mediate heave on the interior of a house is to check sewer drains as well as the supply line and modify the drainage around the exterior of the house. Once the moisture has been stopped; in 6 to 12 months you can re-measure the floor to see if your actions were effective. If proven effective, then you can cosmetically repair the home.
If the monometer survey shows settlement, the proper repair is using helical piers around the perimeter of the house with the settlement problem. Generally, this is more effective than pressure grouting because it provides a load bearing product that can be warranted to last as long as the foundation of the house. Your home is typically your largest investment; attention to the foundation will preserve your equity for years to come. Give us a call and see what certfied foundation specialist can provide for you.