Why did an Edmond slab house settle again two years after piering?

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

Edmond20251-story house, built about 1967, about 1,035 sq ftslab-on-grade

In short: A small 1967 slab house in Edmond had 21 exterior piers, 1 garage pier and interior slab injection installed in 2023. By late 2025 it showed additional settlement at the front, rear and north side ¹. The engineer pointed to continued settlement at pier locations, erosion and poor grading. The engineer specified adjusting or replacing 7 piers with steel piers, adding 1 pier where spacing was excessive, and a list of drainage improvements ¹.

What did the house show?

The engineer inspected the house in November 2025 and issued the report in December ¹. It is a one-story house of about 1,035 sq ft, built about 1967, on a slab-on-grade ¹.

Repair history and observations ¹:

• 2023: 21 exterior piers, 1 pier inside the garage, and interior slab injection.
• Since then, additional settlement at the front, rear and north side, seen as drywall corner and baseboard separations.
• A southwest bedroom closet door binding.
• A living and kitchen ceiling crack, which the engineer attributed to truss movement and described as not structural.
• Erosion and poor grading. A north-side walk traps water by the kitchen and utility room.

What did the engineer find was causing it?

The engineer described continued settlement at pier locations and stressed surface water, grading and drainage. Possible under-slab leaks were also raised ¹.

What repair was specified?

• Adjust or replace 7 of the existing piers shown on the report's figure. Replacement piers must be steel ¹.
• Add 1 new pier on the north side "due to excessive spacing" ¹.
• Afterward, repair drywall and trim, seal exterior cracks, tuck-point, and use elastomeric caulk ¹.
• Suggested items ¹:
  • a plumbing leak test
  • downspout extensions of at least 36 in., or underground pipe to daylight
  • ground sloped at 1 in. per 12 in. within 4 ft of the house
  • removal of beds that trap water
  • surface drains
  • compacted fill with vegetation
  • an option for a sloped concrete walkway

The report states its plan is not an engineered location plan. The contractor sets final pier lengths, locations and count, and any bad footing or stem wall must be repaired before piering ¹.

What does this case show about Oklahoma foundations?

• OKC-area soils include clay subsoils over shale. The USDA describes the Bethany series, with its type location in Oklahoma County, as formed in loess or alluvium over Permian shale. Its subsoil is silty clay loam to clay with 35 to 45 percent clay ². The record does not identify the soil series at this site; Bethany illustrates the clay subsoils mapped in the county.
• Drainage was part of the scope on a piered house. ASCE's homeowner guide for shrink-swell soils recommends grade falling at least 3 inches in 5 feet and downspouts discharging at least 3 feet away. It also notes that leaks in sewer or water lines can cause localized movement ³. The engineer's drainage list (36 in. extensions, 1 in. per 12 in. within 4 ft, leak test) covers the same items ¹.
• Spacing is part of the design. The engineer called out excessive spacing on the existing layout as a reason for an added pier ¹.

Related

• Pier Uplift or Movement After Repair
• Loads Pier Spacing and Capacity
• Surface Drainage and Grading
• Truss Uplift (Mimic)
• OKC Metro
• Bethany soil series