What did an engineer specify for a previously piered Sand Springs house?

Reviewed by Preston, Oklahoma foundation repair consultant · Updated 2026-10-14

Sand Springs20252-story wood frame, brick veneer; garage addition and a former garage converted to living spaceslab-on-grade with continuous perimeter footings (floating floor slab)

In short: A two-story brick-veneer house in Sand Springs had brick cracks on three sides, a chimney separating from the walls and cracks throughout the interior. It had been piered before, with no records available ¹. The engineer attributed the movement to active clay, insufficient earlier piering, and differential movement between the original house and its additions. The scope was 21 perimeter steel piers, 10 to 15 interior helical piers with foam injection, and plumbing and duct checks ¹.

What did the house show?

The engineer inspected the house in May 2025 ¹. It is a two-story wood-frame house with brick veneer. The garage is an addition, and a former garage was converted to living space. The foundation is a slab-on-grade with continuous perimeter footings and a floating floor slab ¹.

Observed conditions ¹:

• Brick cracks from hairline to 1/4 in., and previously patched cracks, on the north, south and east walls and the northeast and southeast corners.
• The chimney separating from the walls.
• Previous piering, with no records available.
• Interior cracks throughout, at doors, closets and the living room.
• Uneven upstairs floors from minor framing sag, with no repair specified for that.

What did the engineer find was causing it?

The engineer named three factors ¹:

• Shrink-swell of active clay.
• Earlier piering that was not enough.
• Differential movement between the additions and the original house.

What repair was specified?

Perimeter (item 1). 21 perimeter piers, shown at 9 ft dimensions on the plan, with equal spacing where none is given ¹. The engineer's pier specification requires ¹:

• steel piers only, unless another system is approved by the engineer
• penetration at least 10 ft below the bottom of the foundation into firm, stable strata
• a detail showing the steel pier driven to refusal on bedrock (blue shale)
• a pier log for every pier: depth, type, diameter, driving pressure and amount of lift
• mortar removed from patched cracks near piers before lifting
• a 6x6x1/2 in. angle iron under the footing where a pier falls near a crack
• a call to the engineer if old shallow concrete piers are found

Locations and count may change for footing conditions ¹.

Interior (item 2). Helical piers under load-bearing walls, about 6 ft on center, with foam injection elsewhere on a roughly 6 ft port grid. The foam is to be warranted. The engineer estimated 10 to 15 interior piers, with cracks stitched at 18 in. ¹.

Other items. A plumbing test before and after the work, a camera inspection of the in-slab ducts, and replacement of fiberboard attic flooring with plywood or OSB ¹.

What does this case show about Oklahoma foundations?

• Shale is both the problem and the target. A federal survey of expansive materials identifies clay-rich sediments and shales as the most troublesome expansive materials ². In this specification, the piers are driven through the active soil to refusal on shale bedrock ¹.
• Clay moves with moisture. ASCE's homeowner guide explains that clay expands when wet and shrinks when dry, and that uneven moisture changes cause more damage than uniform ones ³. The engineer's diagnosis here was shrink-swell of active clay ¹.
• Undocumented earlier repairs complicate the next one. The house had been piered before, but with no records the engineer could not tell how deep or how hard those piers were driven ¹.
• Additions move on their own. The engineer expected independent movement at the joints between the original house and its additions ¹.

Related

• Additions and Mixed Foundations
• Differential Movement at Additions
• Steel Push Piers
• Helical Piers
• Chimney Separating or Leaning
• Shale Weathering and Bearing Strata