Reasons Why a Floor Would Be Sloped

Floor Support Issues

• One reason for a floor to be sloped is the deterioration or movement of the supports immediately below the floor. These include the floor joists that provide structural support or the plywood sub-floor that holds the hardwood, tile, carpet or stone flooring material above. Improper installation, damage from a disaster and simple deterioration due to temperature and moisture exposure can all cause the supporting elements below a floor to change position and shape, allowing the floor to slope.

Foundation Problems

• Problems with a home's foundation can also cause floors to slope. The problem may affect the floor in a single room or several floors throughout a home, depending on the location and severity of the damage. Foundation damage that leads to sloped floors can come from poor construction workmanship or an event such as an earthquake that alters the land below and around the home.

Intentional Sloping

• Some floors are sloped intentionally, which is usually done to allow water to run toward a drain or doorway, preventing it from pooling up elsewhere and damaging the floor. For example, the floor in a bathroom may slope toward a drain. Shower and tub floors always slope slightly for the same reason. Basement and garage floors may also include slight slopes to allow water to run to a drain or toward a door where it can leave the home.

Diagnosis and Repair

• Unless your floor begins to slope immediately after a natural disaster, determining the cause can be difficult. Building experts and inspectors can take measurements that will determine whether your foundation is intact. Visual inspections also help identify the cause of a sloping floor and whether the problem is likely to get worse over time. Repairing a floor's support involves removing the existing floor to add a new sub-floor or joists. Repairing a home's foundation is an even more costly and complicated process, involving jacking the home up and digging around the foundation.