# What Do Stair-Step Cracks in Brick Mean?

> Stair-step cracks in brick can come from settlement, heat and moisture movement, lintels or missing joints. Learn what to check, then decide on the next step.

URL: https://truecoursemasonrynewark.com/guide/stair-step-cracks-in-brick/

A stair-step crack means part of the wall has moved relative to the rest, and the movement found its way along the mortar joints. Foundation settlement is one possible cause. Others include thermal and moisture movement in the brick, a rusting lintel, a long wall with no expansion joint, and framing movement. The pattern alone cannot tell you which.

That is the honest starting point for stair step cracks in brick. [True Course Masonry Newark](https://truecoursemasonrynewark.com/) repairs cracked brick walls across Newark and Essex County once the cause is understood, with the work carried out by licensed and insured contractors. This guide covers the main causes, the clues that separate them, how to monitor a crack, and when it needs a structural engineer rather than a mason. For the repair work itself, see [masonry repair](https://truecoursemasonrynewark.com/masonry-repair/).

**Key takeaways**

- The stepped shape tells you the joints were the weakest path, not what pushed or pulled.
- Width that tapers, offset bricks, growth over time and racked openings are what separate a serious crack from a minor one.
- Brick grows slowly with moisture and moves daily with temperature. Long runs without expansion joints crack at predictable spots.
- Cracks that start at window or door corners point first to the lintel.
- Patching a crack that is still moving only hides it until the next season.

## Why cracks step along the joints

In most walls the mortar is weaker than the brick. When the wall is strained, it relieves the stress by breaking along the joints, and because bricks overlap from course to course, the break alternates between a bed joint and a head joint. The result is the staircase. It is the same whether the force came from below, from the side or from the brick itself. That is why the shape is a clue about where the wall was weakest, and not a verdict on the cause.

## Settlement is one cause, not the only one

Settlement does produce stair-step cracks. When one part of a foundation drops or rotates relative to another, the masonry above tries to span the gap and cracks diagonally, often from a corner of the building or an opening toward the low spot. Settlement cracks tend to be wider at one end than the other, may show bricks offset across the crack, and often come with sticking doors or windows, sloping floors or a crack that continues into the foundation wall.

Newark-area records do not point to a single dominant soil cause. No local evidence was found of expansive shrink-swell clay in Newark, and the city's low eastern ground around the [Ironbound](https://truecoursemasonrynewark.com/service-areas/ironbound/), much of it former marshland, is a different setting from the rising ground toward [Forest Hill](https://truecoursemasonrynewark.com/service-areas/forest-hill/) and the Watchung ridges. Where a house sits on old fill, beside a regraded lot or near a leaking drain, the ground under one corner can behave differently from the rest. None of that can be read from the crack.

Structural foundation repair is a separate trade and is not offered here. If an evaluation points to the foundation, a structural engineer sets the scope and foundation specialists carry it out; the masonry repair comes afterward.

## Other causes that make the same pattern

**Thermal and moisture movement.** Clay brick expands as it warms and slowly grows as it takes on moisture over its life. The Brick Industry Association's Technical Note 18A explains that walls expand toward their ends, so stress concentrates at corners, offsets and setbacks, and that cracks commonly run from the corners of regularly spaced windows, where more brick above and below the openings moves more than the narrower piers between them. A long south- or west-facing wall heats and cools more than a shaded one; NOAA counts about 28 days a year at 90°F or above at Newark, against a winter of frequent freezing nights.

**Missing or bridged movement joints.** Newer veneer walls are designed with vertical expansion joints. The BIA recommends spacing them no more than about 25 feet apart on brickwork without openings and placing them near corners and at offsets. Where a wall was built without them, or they were filled with mortar later, the wall makes its own joints by cracking. Brick expansion joints are not the same as the control joints used in [concrete block walls](https://truecoursemasonrynewark.com/block-wall-repair/), where the block shrinks instead of growing.

**Lintels and openings.** A steel angle over a window that rusts expands and pushes the brick above it, and a lintel that sags lets the brick drop. Either starts a crack at the corner of the opening that steps upward. The [cracks above windows guide](https://truecoursemasonrynewark.com/guide/cracks-above-windows-brick/) covers this in detail.

**Framing, roof and floor movement.** Where brick is tied to a wood frame or carries floor joists, shrinking or deflecting framing, or roof thrust at the top of a wall, can open cracks in the masonry.

## Clues worth recording

| Observation | What it suggests | Why it matters |
| --- | --- | --- |
| Crack wider at one end | Rotation or settlement toward the wide end | Points to differential movement |
| Bricks offset across the crack, in or out of plane | Real displacement | A red flag for engineering review |
| Crack starts at a window or door corner | Lintel or opening movement | Check the steel and bearing |
| Cracks near a corner on a long wall | Expansion | Check for movement joints |
| Crack opens in winter and closes in summer | Thermal cycling | Often less serious, still needs a flexible fix |
| Crack keeps widening across seasons | Active movement | Needs evaluation before repair |
| Doors and windows nearby sticking | Opening racked by movement | Supports settlement or framing causes |

No single row proves a cause. Two or three together start to narrow it.

## How to monitor a crack

Monitoring turns a worrying crack into evidence. Mark fixed points at the widest spot and at each end, measure and photograph them against a ruler, and repeat every month or two through a full year so you capture both winter and summer. A crack that opens and closes with the seasons tells a different story from one that only gets wider. Keep notes on rain, freezes and any work done nearby. Stay on the ground; do not climb a ladder to reach a crack high on a wall.

## When it needs an engineer, and when it can be planned

**Have a structural engineer evaluate it first if:**

- bricks are offset across the crack, or the wall bulges or leans near it
- the crack is clearly widening over weeks or months
- it continues down into the foundation, or floors and openings have shifted
- it runs through a loadbearing wall and through the bricks themselves
- masonry near it is loose overhead

The [engineer or mason guide](https://truecoursemasonrynewark.com/guide/when-a-masonry-crack-needs-an-engineer/) goes through these red flags in more depth, and the [bulging brick wall guide](https://truecoursemasonrynewark.com/guide/bulging-brick-wall/) covers out-of-plane movement.

**Usually a masonry repair to plan when:**

- the crack is fine, even in width and has not changed over a year of watching
- it sits at a corner or long run consistent with expansion, with no offset
- the wall is plumb and in plane, and nearby openings work normally

## How the repair follows the cause

Once movement is understood, the repair matches it. Stable cracks are usually cut out and repointed in a compatible mortar, with cracked bricks replaced, as the [brick repair](https://truecoursemasonrynewark.com/brick-repair/) page describes. Expansion cracks often call for a new expansion joint, sealed with a flexible sealant rather than mortar, so the wall has somewhere to move. Lintel-driven cracks need the steel dealt with through [lintel replacement](https://truecoursemasonrynewark.com/lintel-replacement/). Settlement goes to an engineer and the foundation trade before the brick is touched.

For budgeting, national cost guides put brick wall repair at roughly $10 to $30 per square foot, with many repairs between $500 and $2,500. That is a national range, not a quote; hidden damage behind the face is the usual reason a crack repair costs more. The [masonry repair cost guide](https://truecoursemasonrynewark.com/guide/masonry-repair-cost-newark/) breaks it down.

## Start with a record

Start monitoring this week: mark the crack, photograph it against a ruler and note the date. Look at the nearest window and door for cracks at their corners and check whether they still open freely. Bring that record to a first look through the [contact page](https://truecoursemasonrynewark.com/contact/); a few months of measurements answer questions a single visit cannot.

## Frequently asked questions

### How do I measure whether a stair-step crack is getting wider?

Pick two or three points along the crack, including the widest, and mark small pencil ticks on the brick on both sides so you measure the same spot each time. Measure the gap with a ruler, a crack-width card or a coin as a gauge, and photograph it beside the ruler. Repeat every month or two through at least one full winter and summer, and write down the date and weather. Do this only where you can reach from the ground safely.

### Does it matter whether the crack runs through the bricks or only through the mortar?

It is a useful clue. A crack that follows the mortar joints means the joints were the weakest path, which is normal for most walls with sound brick. A crack that cuts straight through bricks means the movement or force was strong enough, or the mortar hard enough, to break the units. Through-brick cracking with offset edges deserves an evaluation sooner, but neither pattern proves a particular cause.

### Can a stair-step crack be filled with mortar to keep the water out?

Pointing the cracked joints keeps water out and can be part of a sound repair, but only once the movement has stopped or its cause has been dealt with. If the wall is still moving, new mortar cracks again along the same line. Filling a crack that runs through a designed movement joint is a mistake, because the joint is there to let the wall move.