The Foundation Performance Association has established guidelines for foundation underpinning in Texas.
While there are a lot of specific rules, and some exceptions, here are the five generalized guidelines for pier spacing:
- Pier separation along exterior walls no greater than 8 feet for a single story, and 6 feet for a two story, regardless of pier type.
- A two foot by five foot masonry fireplace shall be supported by 3 piers for single story and 4 piers for two story.
- In a wall setback situation, such as a front porch with entry door, a setback of more than 3 feet and less than 9 feet shall require a minimum of 4 piers.
- A monolithic wing wall of more than 3 feet shall require a support every 8 feet.
- Piling/pier supports shall be placed at each corner where an exterior wall changes direction, with at least one piling support on each side of the corner piling.
When pier/piling spacing guidelines are not followed, often in order to save cost or discount a foundation repair, the foundation may later fail.
Granite Foundation Repair is a member of the Foundation Performance Association.