Look above the windows on many Philadelphia rowhomes and you may see stair-step cracks in the brick. Often, a rusting steel lintel is the cause. Window lintel replacement removes the failing steel and rebuilds the opening so the brick above is fully supported.
We see this problem across South Philly, Kensington and West Philadelphia. Old steel angles rust, swell and push the brick out of place. Patching the cracks without fixing the lintel only hides the issue for a short time.
This guide explains how a proper lintel replacement works and why flashing and weep holes are essential.
Why Steel Lintels Fail
A lintel is the steel angle that carries brick over a window or door. Over time, water reaches it and rust begins.
- Rust jacking. Rust expands and lifts the brick above.
- No flashing. Older openings rarely had a water barrier.
- Blocked drainage. Water sits on the steel with no way out.
- Freeze-thaw cycles. Winter weather speeds up cracking.
How Window Lintel Replacement Is Done
The work is done carefully so the wall stays supported at every step.
- Temporary shoring supports the brick above the opening.
- Brick is removed above the old lintel.
- The rusted steel is taken out.
- A new galvanized or primed steel angle is set with proper bearing.
- Brick is relaid and mortar matched to the existing wall.
The Brick Industry Association publishes technical notes on lintels, flashing and weeps for brick walls.
Thru-Wall Flashing and Weep Holes
A new lintel will rust again if water keeps reaching it. Therefore, flashing and drainage are part of every replacement.
- Thru-wall flashing installed over the new lintel.
- End dams that stop water from running off the sides.
- Weep holes or vents along the bottom course.
- Sealant at the window frame below the lintel.
Repoint the Cracks or Replace the Lintel?
Repointing may be enough when:
- Cracks are fine and not growing.
- The lintel shows no rust or movement.
- Brick is still in its original position.
Lintel replacement makes sense when:
- Rust is visible under the brick.
- Cracks widen or bricks shift.
- Windows are being replaced at the same time.
Warning Signs of a Failing Lintel
- Stair-step cracks rising from window corners.
- Brick bowing above the opening.
- Rust stains running down the wall.
- Windows that stick or will not close.
Ignoring these signs can lead to larger masonry repairs later. An inspection is the safest first step.
Frequently Asked Questions
How long does window lintel replacement take? Many single openings can be completed in a day or two, depending on access and weather.
Will the new brick match? We match brick and mortar as closely as possible to the original facade.
Can lintels be replaced without removing the window? Often, yes. The window is protected during the work.
Do you handle permits? We advise on permits and handle them when required.
Protect Your Brick Facade in Philadelphia
Timely window lintel replacement stops cracks before they become major masonry repairs. Philadelphia Exterior Contractors handles brick, lintels and windows in one project. Learn more about our window replacement services, read our exterior repair blog, or contact our team for an inspection.
