What is Foundation Movement?
Simply put foundation damage is caused by soil movement. The three directions that the foundation can move is: up, down, or inward from exterior soil pressure pushing against your concrete foundation wall. Your foundation can experience all three types of movement- at the same time. The potential movement of your foundation depends upon the soil conditions around your home. These soil conditions range from not expansive to very expansive depending upon where your live. The average potential for soil expansion is around four inches, by can be as high as twelve inches in some areas. This amount of movement can severely damage your foundation and home. It is very important to maintain the integrity of your foundation.
What causes foundation movement?
Shrinking and swelling of expansive soils. Over 90% of all foundation failures can be linked to either improper design or soil related problems. When looking to build a new home, or trying to find out what your current foundation is sitting on, it is worth hiring a soil geologist. During the wetter month of the year, soil will become soaked and begin to swell. The amount of swelling is determined by the expansiveness of the clays and underlying soils. The amount of swelling can vary from nothing to in excess of 12″. During the drier months, soil will lose its moisture and begin to shrink. The amount of shrinkage depends on how much moisture is evaporated from the soil. The more the shrinkage the greater the foundation is likely to settle. Building on expansive clay, compressible or improperly compacted fill soils, or improper maintenance around foundations also causes foundation settlement and movement. Whatever the cause, settlement can destroy the value of structures and will render them unsafe.
Moisture due to poor site drainage & building on non-compacted fill.
Since water or excessive moisture can cause foundation movement or damage, it is very important to keep water away. Moisture can be diverted completely away from your foundation by maintaining or improving the desired elevation (slope away from) the foundation. Sufficient site drainage is extremely important in order to extend and maintain the life of your foundation structure. Water proofing, installation of drainage systems (sump pits and pumps), and French drains are all important factors in maintaining proper stability of your foundation. Building on improperly compacted soils can also affect the amount of foundation movement your home has. This normally occurs when a developer or contractor raises the elevation of the construction site above the undisturbed natural soils. The elevation difference must be taken into account when the design of the foundation is considered. The amount of fill varies upon the desired elevation of the new home of the existing site conditions. When this happens the weight of your home will begin to sink into the soil and allow the foundation to shift and create costly damage to the structure of your home.
Plumbing Leaks
During the initial construction stage of a home, quality piping and fixtures must be used. Plumbing drain lines must be constructed of dense, durable nonabsorbent materials and must have smooth, impervious surfaces, free from unnecessary concealed fouling surfaces. Older homes typically installed either clay drain pipes of cast iron drain pipes. Newer homes typically install either ABS or PVC drain lines. Installation of waste or sewer lines must maintain a slope of at least 1/8″ drop per foot toward the main sewer line in the street. Shifting or improperly installed water and sewer line can leak and add unwanted moisture around your foundation. Water supply lines are normally constructed out of copper. Older homes may still have either lead or galvanized lines coming from the street going into your home. Whether the plumbing leaks are in the water lines or sewer lines, foundation movements will inevitable occur.
How to detect foundation troubles inside the home.
- Cracks in the masonry
- Gaps between bricks, doors and windows
- Bricks leaning away from garage doors
- Gaps between fireplace and house
- Sagging roof line
- Deterioration of building materials
- Structural damage supporting building materials
- Water stains around foundation
- Dirt lower around foundation (negative slope)
- Sinking exterior walls
- Separation around concrete walks and driveway
- Garage door opening sagging
- Uneven window headers and sills
How to detect foundation troubles outside the home
- Cracks in the masonry
- Gaps between bricks, doors and windows
- Bricks leaning away from garage doors
- Gaps between fireplace and house
- Sagging roof line
- Deterioration of building materials
- Structural damage supporting building materials
- Water stains around foundation
- Dirt lower around foundation (negative slope)
- Sinking exterior walls
- Separation around concrete walks and driveway
- Garage door opening sagging
- Uneven window headers and sills