Skip to content
Buffalo Foundation Repairs

Serving Buffalo and nearby areas

Horizontal Crack in Basement Wall in Buffalo, NY

A horizontal crack in a Buffalo basement wall often means soil and frost are pushing the wall in, so get a free inspection and a written price before the next winter.

Call now: (716) 621-3279 or book your free inspection online

Book a free foundation inspection

Tell us what you are seeing. A local specialist calls you back the same business day.

Local to Buffalo

We connect property owners in Buffalo and nearby areas, including North Buffalo, South Buffalo, Elmwood Village, Allentown, Amherst and Cheektowaga, with one independent local foundation repair specialist.

  • Side pressure did it

    In a U.S. Army Corps of Engineers study of Amherst homes, soil pushing in from the side was the main cause of basement wall damage.

  • Weak tops

    In 93 percent of the houses the Corps checked, the basement walls lacked enough support at the top to hold back that pressure.

  • 59 inches of frost

    NOAA engineering data for Buffalo lists a 50-year frost depth of 59 inches and about 53 freeze-thaw cycles a year. Frozen wet soil swells and pushes on the upper part of the wall.

What it costs

Typical published ranges for Buffalo. The contractor's written estimate is the price, and the inspection is free.

WorkTypical range
Inspection and written estimate Free
Seal the crack after bracing $250 to $1,000
Carbon fiber straps, whole wall job $4,000 to $12,000
Wall anchors $1,500 to $2,000each
Bowing wall repair, whole job $4,000 to $15,000
Structural engineer report $300 to $2,000

See typical foundation repair prices in Buffalo

What a horizontal crack looks like

A horizontal crack runs sideways along the wall, parallel to the floor. In Buffalo it shows up in a few common ways.

One long mortar line in block

The crack follows a mortar joint, often three or four rows of block down from the top, and can run most of the wall.

A crack at mid height

In some walls it shows up halfway down, where the push from the soil is strongest.

Stair steps at the ends

The sideways crack turns into a zigzag near the corners. That pattern means the middle of the wall is moving more than the ends.

A ledge you can feel

Run your hand across the crack. If the block above sticks out past the block below, the wall has started to lean or bulge.

Water along the line

The crack gets wet or leaves a white crust after a thaw.

A thin vertical crack in poured concrete is a different thing. Those often come from the concrete shrinking as it dried. A sideways crack is about force.

Why it happens in Buffalo

Soil pushes from the side

Your basement wall is a retaining wall. The soil outside leans on it all the time. The U.S. Army Corps of Engineers studied damaged homes in Amherst and found that soil pushing in from the side was the main cause of basement wall damage. It named four forces: the weight of the soil, swelling clay, water pressure and frost.

Clay that swells

Buffalo sits on the Erie Plain, the bed of old glacial lakes. Much of the soil is clay. The Corps found the lake-bed clay in Amherst has medium to high swell potential. When it gets wet it grows, and it has nowhere to go but into your wall.

Frost and snow melt

NOAA data for Buffalo lists a 50-year frost depth of 59 inches and about 53 freeze-thaw cycles in an average year. Wet soil that freezes against the upper part of a wall expands and pushes. Then about 95 inches of snow a year melts into that same soil. Wet clay is heavier than dry clay, so the push gets stronger right when the soil is softest.

Walls not built for it

In 93 percent of the houses the Corps checked, the basement walls lacked enough support at the top. A hollow block wall with little steel and a weak tie to the house above bends at its weakest line. That line is the horizontal crack.

Watch it or fix it now

Watch, with a plan

A thin, dry horizontal crack with no step and no bulge. Mark the ends and width, write the date, and check after each thaw. Book a free inspection so someone with tools has measured it once.

Fix before next winter

The crack is wider than about a quarter inch, has a ledge you can feel, leaks, or grew since last year.

Call now

The wall bulges in more than about an inch, the top of the wall has slid in past the wood sill, or the crack opened up fast. Say so on the call.

How it usually gets fixed

The fix has two jobs. Stop the wall from moving, then deal with the water and the crack.

  1. Carbon fiber straps are glued to the wall every few feet. They work for walls that have moved a small amount. They are thin and can be painted.
  2. Steel beams stand against the wall from floor to the joists above. They hold walls that have moved more, and some can be tightened over time.
  3. Wall anchors run through the wall to plates buried in the yard. They hold the wall and can pull it back a little over the seasons.
  4. Rebuild the bad section when the wall has moved too far to brace. This means digging outside and laying new block or pouring new concrete.
  5. Seal and drain. After bracing, the crack is sealed. Many Buffalo jobs add an inside drain, because water pressure helped push the wall in the first place.

The ranges below come from national cost guides. Your estimate lists which method fits your wall and why.

Before the inspection

  • Measure the crack length and width and photograph it with a ruler in the shot.
  • Clear a few feet in front of the wall so the inspector can see it top to bottom.
  • Point downspouts away from that side of the house.
  • Do not pile snow against that wall when you shovel.
  • Keep heavy cars and equipment off the ground right next to it.
  • Find any old paperwork on past repairs to that wall.

Frequently asked questions

Is a horizontal crack in a basement wall bad?

It is the crack to take most seriously. Vertical cracks often come from concrete shrinking. A sideways crack usually means something pushed on the wall from outside. Have it looked at, even if it is dry.

Can I just fill a horizontal crack with caulk or hydraulic cement?

Filling it can slow water, but it does not stop the wall from moving. If the wall keeps getting pushed, the filler cracks again. The wall needs bracing first, then the crack gets sealed.

How do I know if the wall is moving?

Hold a long straight board or a tight string along the wall. If the middle sticks out toward you, it is bowing. Mark the crack ends and width with the date and check again after the next thaw.

Do I need an engineer for a horizontal crack?

Not always. If the wall has moved more than about an inch or so, if you are buying or selling, or if the estimates disagree, an engineer's letter helps. National guides put it at about $300 to $2,000.

Does a horizontal crack need a permit to fix in Buffalo?

Structural work often needs one. In the city, permits go through Buffalo Permit and Inspection Services, and each suburb has its own building department. The contractor should pull it.

Will my house fall down?

Almost never suddenly. Most walls move slowly, a little each winter. That gives you time to fix it, but not time to ignore it.

Other services

Common foundation repair problems in Buffalo

Areas we serve around Buffalo

(716) 621-3279 Free inspection