A crack running sideways above a window, or brick lifting at the window corner, usually means the steel lintel over that opening is rusting and expanding. MLM Construction Group repairs brick and lintels on Brooklyn row houses, licensed under HIC #2130570, with 97 Google reviews at 5.0. Call (516) 713-9199.
Every window and door opening in a brick wall needs something to carry the brick above it. On most Brooklyn row houses and small apartment buildings that is a steel angle, called a lintel, sitting on the brick at each side of the opening and hidden behind the face of the wall. You usually see only its bottom edge, a thin line of painted metal above the window head.
Steel is fine as long as it stays dry. Over decades, water gets through mortar joints and failed sealant, reaches the steel, and it rusts.
Rust takes up far more room than the steel it came from. As a lintel corrodes, the layers of rust swell and push upward on the brick above it, a process masons call rust jacking. The steel does not have to be close to failing for this to happen. A lintel that is still strong enough to carry the wall can already be lifting the brickwork and cracking it.
That is why lintel problems show up as damage in the brick, not in the steel. By the time you see the steel itself sagging, the job has become much bigger.
From the sidewalk, look at the brick right above each window. The classic sign is a horizontal crack along the mortar joint just above the lintel, often running a little past each side of the opening. Next is step cracking, a diagonal crack following the mortar joints up and away from the top corners of the window.
Look at the bottom edge of the steel. Flaking paint, rust stains running down onto the window frame or the brick below, and steel that looks thick and layered rather than flat all point the same way. Bricks at the end of the lintel that have shifted or cracked, and a window that has started to stick, complete the picture.
Inside, cracks in the plaster at the top corners of the window and water staining at the head after a storm are the same problem seen from the other side.
The brick above the opening is carefully taken down, with the wall above supported while the work is done. The old lintel comes out. Depending on its condition, it is either replaced with a new galvanized or primed steel angle or, if the steel is still sound, cleaned back to bare metal and coated.
Then comes the part that decides whether the repair lasts: flashing. A through wall flashing is installed over the new lintel with end dams at each side, so water that gets into the wall is directed out at the face rather than sitting on the steel. Weep openings are left in the joint so that water can escape. Without that, a new lintel will start rusting again on the same timetable as the old one.
The brick is then relaid, matching the existing brick and mortar as closely as possible, and the surrounding joints are repointed. On larger openings or higher floors, scaffolding or a lift is needed, and depending on the scope a DOB permit may be required. We tell you which at the assessment.
Pointing a crack above a rusting lintel looks tidy for a season. The rust keeps growing behind it and the crack opens again, usually wider, because the cause has not been touched. Worse, sealing the face tight can trap more water at the steel.
Caught early, a lintel can often be dealt with on its own. Left for years, the brick above starts to bulge, the end bearings crush, and the repair grows into rebuilding a section of the facade.
Price depends on the width of the opening, which floor it is on, how the wall is reached, how much brick has to come down, and how many openings need work at once. Doing several lintels in one visit is much more economical than one at a time, because access is often the biggest part of the cost.
MLM Construction Group inspects and photographs every opening, tells you which lintels need replacing now and which can wait, and gives you a written price for each. Licensed under NYC DCWP HIC #2130570 and fully insured. See our brick pointing and masonry page or call (516) 713-9199.
Most often a rusting steel lintel. Rust takes up much more space than steel, so as the lintel corrodes it pushes up on the brick above it and cracks the mortar joint along the top of the opening.
It is the term masons use for brick being lifted and cracked by expanding rust on embedded steel, such as a lintel. The steel can still be strong enough to carry the wall while already damaging the brickwork.
Not if the lintel is rusting. The rust keeps growing behind the new mortar and the crack reopens, often wider. The steel has to be dealt with and flashing installed for the repair to last.
The brick above is taken down with the wall supported, the old lintel is removed and replaced or cleaned and coated, through wall flashing with end dams and weeps is installed, and the brick is relaid and repointed to match.
It depends on the scope of the work and the building. Some lintel and facade repairs require a DOB permit. We confirm what applies to your building at the assessment.
It depends on the opening width, the floor, access and how much brick comes down. Doing several lintels in one visit costs much less per opening because access is a large part of the price. We give a written price for each opening.
Yes. MLM Construction Group repairs lintels, brick and pointing across Brooklyn, Queens and Manhattan, licensed under NYC DCWP HIC #2130570 and fully insured. Call (516) 713-9199 for a free assessment.