Evansville Tuckpointing Step cracks above windows and at corners: lintel, settlement, or just mortar
A stair-step crack that climbs the mortar joints from the corner of a window or up a corner of the house is almost never a mortar problem by itself. Something moved. On Evansville’s mid-century brick, the usual answer is a rusted steel lintel, replaced at $400 to $1,500 per opening. On older houses on river-bottom soils, the answer is settlement, and the masonry repair waits until the foundation stops moving. Repointing the crack without finding out which one you have is the most common wasted masonry dollar in this city.
Check this first (twenty minutes, a straightedge and a coin)
- Find where the crack starts. From the top corner of a window or door means the lintel. From a corner of the building running diagonally down or up toward one point means settlement. Along one joint plane with no pattern means mortar.
- Test for displacement. Put a straightedge or a taut string across the crack. If the two faces are still in the same plane, the wall has opened but not shifted. If one side sits proud of the other, something is moving.
- Measure the width. Slide a coin edge in. Hairline is watchful waiting. A quarter inch or more is a real gap and rain is entering it.
- Look at the steel. Above the window, at the top of the brick opening, is there a painted steel angle? Rust bloom, orange staining down the brick, or a lifted mortar joint directly on the steel is a rusting lintel. Steel expands as it rusts and pushes the wall apart.
- Check inside. Cracks in the drywall or plaster at the same corner, doors that stick, or a sloping floor point at movement rather than a lintel.
- Date the crack. Photograph it with a coin taped beside it and shoot it again in two months. A crack that is not growing is a different conversation than one that is.
What is usually wrong
| What you are seeing | Likely cause | Fix and cost |
|---|---|---|
| Cracks from both top corners of a window, rust staining, joint lifted on the steel | Rusted steel lintel expanding | Lintel replacement, $400 to $1,500 per opening |
| Diagonal crack running to one low corner of the house, doors sticking inside | Foundation settlement | Foundation assessment first, then masonry repair |
| Crack follows joints only, no displacement, mortar crumbly everywhere | Mortar failure and thermal movement | Repoint, $8 to $20 per sq ft, $500 to $800 minimum |
| Crack at the corner of an addition or porch meeting the main wall | Two structures moving separately | Repoint or a flexible joint, spot work $300 to $900 |
| Crack under a sill spreading down, sill cracked too | Failed sill loading the brick below | Sill repair or reset, $300 to $1,200 each |
| Long horizontal crack with the wall pushed out | Wall movement, not a step crack | See the bowing wall page before quoting |
Ranges come from the pricing page. The repair itself is covered on the lintel and sill replacement page, and our guide step cracks over the window goes deeper on telling the three causes apart.
Why Evansville sees so many of these
Two reasons, one modern and one old. Steel: the brick ranches and split-levels that fill the East Side, Newburgh, and the post-war edges of the city carry their wide openings on exposed steel angles. Once the shop coat fails, the steel rusts, and rust occupies far more space than the steel it came from. The wall has nowhere to go but up and apart. That is why the crack starts precisely at the top corners of the opening.
Soil and water: Evansville sits on the Ohio at the bottom of the Pigeon Creek drainage, and the older neighborhoods are built on river-bottom and terrace soils that shrink and swell with moisture. The city has been above the 42-foot flood stage 41 times since 1940 by the Levee Authority’s count, and a wet spring followed by a dry August moves clay soils. Add 45.31 inches of rain a year and downspouts that discharge next to the foundation, and the same corner of the same house works up and down for decades.
When it is structural, not cosmetic
Call it structural when the crack shows displacement out of plane, when it is wider than a quarter inch, when it is measurably growing, when the brick course over an opening has sagged, or when the crack shows up inside the house too. Any of those means the wall is carrying load in a way it was not built to. A crack that is stable, tight, and confined to the joints can be repointed as part of ordinary maintenance, and the crumbling mortar page covers that work.
What to expect on the call
Photograph the whole elevation, then the crack close up with a coin taped next to it, then the head of the window showing the steel. Say whether anything inside cracked at the same time. What you should hear back is a cause before a price. If the answer is a lintel, the scope is shoring the brick above, cutting out the rusted angle, setting a new galvanized lintel, and resetting the units, and the crack gets repointed at the end rather than at the start. If the answer is settlement, the masonry quote should wait for the foundation, and any mason who wants to repoint a moving crack today is selling you the same repair twice.
Frequently Asked Questions
What causes stair-step cracks in brick?
Three things, and they are not repaired the same way. A rusted steel lintel over an opening expands and lifts the brick above it, which cracks up and out from the top corners of a window or door. Foundation settlement pulls a corner down, which cracks diagonally toward the low point. Plain mortar failure cracks along the joint without displacement. Repointing the wrong one is money spent twice.
How much does it cost to fix a step crack in Evansville?
It depends on the cause. Replacing a rusted steel lintel runs $400 to $1,500 per opening, including shoring and resetting the brick above it. Repointing a crack that is only mortar is part of a repoint at $8 to $20 per square foot against a $500 to $800 minimum. Settlement is a foundation question first, and the masonry repair follows the foundation work.
Is a step crack in brick serious?
A hairline crack that has not moved in years and shows no displacement is usually not urgent. Treat it as serious when the two sides of the crack no longer line up, when it is wider than about a quarter inch, when it is growing, when the brick above a window is sagging, or when the same crack appears inside on drywall or plaster.
Why do so many Evansville ranch houses have cracks over the picture window?
Steel lintels. Mid-century brick homes here span wide openings with an exposed steel angle, and once the paint fails the steel rusts. Rusting steel expands to several times its original thickness, which lifts the brick course sitting on it and opens a stair-step crack from each top corner of the opening.