Foundation Crack Repair in St. Paul

Injection sealing for poured walls, tuckpointing and reinforcement for block walls.

Almost every basement has cracks. Most are harmless shrinkage from when the concrete cured. A few are the first sign that soil pressure or settlement is moving the foundation. Three things tell them apart: how wide the crack is, which direction it runs, and whether it's getting bigger.

What the direction tells you

• Vertical cracks are the most common and usually minor, especially in poured concrete.
• Diagonal or stair-step cracks point to uneven settling, or to a wall that isn't well tied to the house framing.
• Horizontal cracks are the most serious. They usually mean soil is pushing the wall inward. See bowing walls.

Poured concrete vs. block

In poured concrete walls, you'll see individual cracks through the concrete. A web of hairline cracks, or widely spaced vertical cracks under 1/8 inch, generally means the concrete shrank as it cured.

In block walls, cracks follow the mortar joints. Blocks are hollow, so injection doesn't work well on them. Block cracks are usually a sign of wall movement, and the fix is to stop the movement.

In stone foundations, common in older St. Paul homes, the issue is usually mortar washing out rather than cracks. See our St. Paul page.

How to monitor a crack

1. Mark both ends of the crack with a pencil line and write the date next to it.
2. Measure the width at its widest point. A coin or a drill bit makes a quick gauge.
3. Take a photo with a ruler next to it.
4. For more precision, buy an inexpensive crack monitor. It's a two-piece plastic gauge with crosshairs that shift on a grid if the crack moves.
5. Check through a full Minnesota winter and spring thaw. That's when foundations move the most.

A crack that grows past its pencil marks, gets wider, or starts letting in water needs a closer look.

How to repair foundation cracks

How you repair a cracked foundation depends on whether the crack is still moving. A stable crack in a poured wall can be injected and forgotten. A crack that's still opening is a symptom, and sealing it just hides the symptom.

Leaking tie holes in poured walls

Poured concrete walls are held together by steel form ties while they cure. The snapped-off ends are left in the wall, and over time they rust and expand, cracking the concrete around them. Water then comes in through small round spots in a regular grid. Hydraulic cement patches often fail because the cement shrinks as it cures and doesn't stick to wet concrete. Low-pressure polyurethane injection or expanding plugs last longer.

Minnesota frost depth

Minnesota's building code requires footings at least 42 inches deep in the southern and central part of the state, including Ramsey and Washington counties, and 60 inches in the north. Older homes don't always meet today's standard, which is one reason freeze-thaw movement shows up as cracks in older foundations.

Cracked foundation repair cost

Concrete foundation repair by injection usually runs $300–$1,000 per crack, depending on length, access, and whether it's epoxy or polyurethane. If the crack is a symptom of wall movement, budget for the wall repair instead. See the cost guide.

Questions homeowners ask

Areas we serve

St. Paul, Woodbury, Maplewood, Oakdale, Cottage Grove, Stillwater, West St. Paul, North St. Paul, Lake Elmo