Foundation Education

What causes foundation problems?

CLAY SOIL

  • BLUE MARL,  COLICHE,  BLACK GUMBO•SHRINK/SWELL
  • NON-TRANSMITTAL OF MOISTURE
Our soils are made up of @ 5 components.  The most prevalent are Blue Marl (a type of clay), Black Gumbo (a very expansive and sticky clay), and Coliche (hardened calcium carbonate which binds these clays together).

FOUNDATION FLEX

  • AGE-RELATED STRENGTH
  • EVENTUAL FAILURE
Because of our expansive clay soils, our foundations are always flexing and bending season after season, year after year.  Just like bending a pencil back and forth, the foundation gets weaker and eventually loses it’s ability to remain level.  This is why newer homes (less than 15 years old) rarely have foundation settlement issues.  On average, homes reach about 20 years old before any significant signs of foundation failure become evident.
KNOW THE WARNING SIGNS

WARNING Signs Inside the Home3136

Sheetrock Cracks Sheetrock is brittle and can be cracked easily. Foundation movements, wall movements, termite damage, even slamming doors can result in Sheetrock cracks.

Door Catch Plates Foundation settlement will often result in doors which do not close and latch properly. Many home owners and even handymen will simply move the catch plates in order to make the doors work. Look to see if the wood has been cut and the plate has been moved from it’s original position.

Door Gaps Again, foundation movement can often result in doors not fitting properly. Look to see if doors are square within their frames.

Doors Sticking Depending on the direction of foundation movement, doors can either have a large gap as in the previous picture, or can be sticky or not close at all as shown here.

Shaved/ Cut Doors Often home owners and handymen will cut the tops (and bottoms) of doors to prevent them from sticking and allow them to close. Sometimes this is easy to recognize as the cut is not straight.

Doors Re-hung Often doors which are badly out of alignment will be completely removed and re-hung, as this door was. Notice that the top of the door frame is not level with the ceiling as it would have been at original construction.

Slopes If you sense sloping floors, you are usually right. And if you can feel the slope it is almost always enough to cause concern

WARNING Signs Outside the Home3136

Brick Cracks Brick cracks are a sign of movement.  The larger the crack, the more severe the movement.  Sometimes bricks and mortar will crack from normal seasonal movements and/or thermal expansion, so a crack in itself does not always mean you have foundation problems.

Around the Windows Foundation settlement is almost always rotational, and will create separations at openings in the brick walls – such as windows, doors, and garage doors.

Garage Doors Garage walls are the most prevalent area to experience abnormal movement.  In most cases the brick will rotate away from the garage door frame.  This crack/separation will be wider at the top and narrow at the bottom.

Frieze Boards Frieze boards are the trim boards at the top of the brick just under the eaves of the roof.  These boards are cut to fit together when the house is built.  If these boards are pushed apart by the brick, this indicates adverse foundation movement

• MULTIPLE PATCHES4318
• WATER STAINS
• NO NEED FOR SPEED LIMIT SIGNS

Roads close by  can cause severe damage to foundations. When heated, concrete roads expand then shrink as they cool. Streets push against driveways and driveways push against the foundation walls which results in deflection and buckling. Something has to give.

Vibrations from street traffic can also affect your foundation. If your home is close to major roads, especially roads with large trucks at high speeds, the vibrations will be passed to your foundation. Since most foundations are not built to handle these constant vibrations, they can be weakened and damaged over the years.

Other Causes of Foundation Failure

  • Cut and fill land development
  • Water run-off
  • Moisture trapped by flowerbeds
  • Water ponding
  • Low-density soils
  • Under-compacted fill
  • Negative drainage or plumbing leaks
  • Construction when soil was dry and it heaved later
  • Rebound—cut hillside relieves overburden pressure and exposes dry, dense soil
  • Settlement—drying clays shrink at different rates causing foundation failure
  • Subsurface hydrostatic Liquefaction—when fill soil is dumped over an old, wet-weather stream or hillside seep. The under layers become saturated, liquefy and flow from under the upper layers.
  • Total collapse of surface soils—caused by saturation, deforestation and removal of support soils at the toe of the hillside