Why foundations move in McKinney
All of Collin County except a sliver of its western edge lies in the Blackland Prairie, according to the Handbook of Texas, and the prairie’s soils are deep clay. The USDA’s soil survey of the county found one soil, Houston black clay, covering 370.1 square miles on its own. Today’s official description rates its shrink-swell potential as high.
That clay works like a sponge with a schedule. In short: heave when wet, settle when dry, according to a Texas Department of Licensing and Regulation bulletin, which calls shrink-swell soil a very common cause of foundation problems in the state. North Texas weather makes the swings bigger than most places get:
- Rain comes in extremes. The National Weather Service says annual rainfall at DFW varies from less than 20 to more than 50 inches. 2014 brought 21.32 inches; the very next year, 2015, was the wettest on record.
- Dry spells are long. DFW went 67 days without measurable rain from mid-July to late September 2026.
- The city plans for it. McKinney’s own street standards require moisture conditioning of the subgrade, aiming to keep potential vertical rise to 4 to 4.5 inches. A house slab gets no such treatment after it’s built.
Most McKinney houses are young: the median home was built in 2007, and 73% of homes date from 2000 or later. Most Texas houses sit on slab-on-ground foundations, which the clay can tilt or bend as a single piece. Newer doesn’t mean immune: the soil under a 2010 slab is the same soil.
Signs your foundation is moving
These are the signs the Texas Real Estate Commission and the Texas Section of the American Society of Civil Engineers (ASCE) tell inspectors to look for:
| What you see | Where | Could also be |
|---|---|---|
| doors that bind or don't latch | Interior doors, especially near the middle of the house | Humidity, worn hinges |
| cracking of drywall walls and ceilings | Above door and window corners | Normal drywall shrinkage, settling tape |
| diagonal (stair-stepping) cracks in brick | Exterior brick, near corners | Mortar shrinkage if hairline and not growing |
| sloping floors | Hard floors, rolling a ball | Uneven framing or subfloor |
| frieze board separations | Where the wall meets the roofline outside | Wood shrinkage |
| Cracks in a concrete floor 1/16 inches across or wider | Garage slab, under flooring | Normal curing cracks if narrower |
One sign on its own proves little. An ASCE homeowner guide puts it plainly: the more of these signs you see together, the higher the probability the foundation has moved. The Foundation Performance Association goes further: not all distress is foundation movement, and a good inspection rules out the lookalikes. The warning signs page covers each sign in more detail, with the common lookalikes.
Call to schedule an inspection
Foundation repair in Collin County: the main fixes
Piers under a slab. The most common repair here. The contractor digs beside the beam, drives or drills piers down to firmer ground or rock, and lifts the low area back toward level. Pier type, depth and count drive the price; the pier types guide compares them.
Pier and beam repair. Some older houses sit on piers and beams instead of a slab; 8% of McKinney homes were built before 1980. Fixes range from re-shimming to replacing piers or beams; Angi puts re-shimming around $1,600.
House leveling. Lifting the house back toward level, either with shims on pier and beam or with piers under a slab. Expect some cosmetic cracking afterward.
Drainage and soil moisture. Gutters that dump at the foundation, beds that hold water, and yards that slope toward the house all make the clay swing harder. Drainage work doesn’t lift a house, but it can slow movement.
Inspection and a second opinion. Every repair starts with an inspection and, usually, a floor elevation survey. For a big job, a second plan or an independent engineer’s evaluation is worth the cost; the engineer guide explains when.
What foundation repair costs in McKinney
Published averages give you a yardstick, not a quote:
| Item | Typical cost | Source |
|---|---|---|
| Foundation repair, national average | $5,174 | Angi |
| Foundation repair, Dallas average | $5,223 | Angi |
| Average DFW job at one large contractor | $8,379 | Olshan (contractor figure) |
| Piers, per pier | $1,000–$3,000 per pier | HomeAdvisor |
| Piers on a typical slab job | 5–15 piers | Olshan (contractor figure) |
| Foundation inspection | $300–$750 | HomeGuide |
| Structural engineer’s report, average | $550 | HomeAdvisor |
The gap between the national average and one contractor’s DFW average is the clay: repairs here usually mean piers, and piers are priced one at a time. The foundation repair cost page breaks the price down line by line and explains why two quotes for the same house can differ by several piers.
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McKinney’s permit rule
McKinney is stricter than many cities. Its foundation repair guidelines count leveling, pier or footing replacement, shimming and floor-system repair as foundation repair, and set out three steps:
| Step | McKinney’s rule |
|---|---|
| Permit for the repair | yes |
| Engineer’s letter and drawings showing the affected areas and any plumbing test | yes (before permit) |
| Closing the permit | Final Engineer's Report required |
That’s good news for homeowners. It means a licensed engineer has signed off on the plan and checked the result. Ask every contractor who pulls the permit and who provides the letter and final report. The McKinney permit guide walks through each step. Neighboring cities set their own rules: see Allen, Frisco and Plano.
Before you sign a repair plan
Texas has no state license for foundation repair contractors: a 2011 Senate bill analysis found no state regulation of foundation repair contractors (2011). The plan and the warranty are your protection, so check:
- The elevation survey. Ask for a copy of the readings the plan is based on. The Foundation Performance Association notes that a second survey six to twelve months later can show whether movement is ongoing.
- The pier count and why. Number, type, depth and location of every pier.
- The permit and engineer. Who pulls the permit, who writes the engineer’s letter, and who provides the final report.
- The warranty. What it covers, how long it lasts, and whether it transfers to a buyer and for what fee.
- Plumbing. Whether the plumbing will be tested before and after the lift, and by a licensed plumber.
- The alternative. The Texas ASCE guidelines note that an owner may reasonably choose cosmetic repairs instead of underpinning. For minor, slow movement, that can be the right call.
Get at least two written plans before you agree to a large repair.
Call to schedule an inspection
Who does the work
When you call or send a request, a local foundation contractor who serves your area confirms a time, inspects the house and gives you a written plan and price. Work is done by independent local contractors. Pricing and availability are set by the contractor serving your area.