Austin – Improve Foundation Performance

Expansive Clays. Can’t live with them. Can’t live without them.

If you live in the Austin or the South Texas Area, you know the havoc these soils can wreak on a slab on grade foundation system. But do you know how simple it is to prevent clay soil slab damage while at the same time improving its performance potential?

To help lower the potential of future concrete foundation distress and residence interior/exterior brittle material cracking occurrences, a homeowner should consider implementing the following non-structural maintenance/code compliance guidance:

• Maintain a uniform soil moisture content along and about the foundation system perimeter where it is reasonable to do so. The following Guidelines below may be followed:

• Excessively wet foundation bearing soils can swell volumetrically causing ground supported foundation systems to displace vertically (“heave” or “settle”) upward or downward over time. Assure bearing depth soils near the foundation perimeter do not become excessively saturated. To the extent allowable, assure uniform bearing depth soil moisture content conditions along the foundation perimeter areas.

• Excessively dry foundation bearing soils can shrink volumetrically causing ground supported foundation systems to displace vertically (“settle”) downward over time. Assure bearing depth soils near the foundation perimeter do not become excessively desiccated. To the extent allowable, assure uniform bearing depth soil moisture content conditions along the foundation perimeter areas.

• The Post Tensioning Institute Publication “Design and Construction of Post Tensioned Slabs-on-Ground” states:

• Watering should be done in a uniform, systematic manner as equally as possible on all sides of the foundation to keep the soil moist. Areas of the soil that do not have ground cover may require more moisture as they are more susceptible to evaporation.

• During extreme hot & dry periods, close observations should be made around foundations to insure that adequate watering is being provided to keep soil from separating or pulling back from the foundation.

• Assure any air conditioning condensate discharge lines direct condensate away from the foundation system perimeter to prevent localized foundation bearing soil saturation.

• Assure any water heater TPRV discharge lines direct their liquid effluent away from the foundation system perimeter to prevent localized foundation bearing soil saturation.

• Attempting to replace expected local climate precipitation by artificially imbibing moisture into the foundation bearing soils with appliances (example: soaker hose or irrigation system) may negatively impact the structural efficacy the foundation system. No known authoritative treatise or code based protocols exist which provide approved instructions for their safe, hazard free, long term use.

Austin – Improve Foundation Performance Austin Austin – Improve Foundation Performance- Improve Foundation Performance