How to Make a Brick Lintel Repair

Traditional brickwork is more than just a facade on the outside of the home. It’s part of the home’s structure, and this material can last for generations if taken care of. When a lintel started to sag on a brick federal-style home with historic roots, the homeowner called Mason Mark McCullough to save the day. With a mix of modern and traditional materials, Mark shows the homeowner what to do.

How To Make a Brick Lintel Repair

1. Start by installing a piece of plywood cut to completely cover the window opening. This plywood will protect the glass and window frame.
2. Remove the bricks above the lintel. Start at the loose bricks above and work your way down. Chisel away at the mortar, and use masonry files to cut any stubborn mortar holding bricks in place. Continue removing bricks to expose the second wythe, or the layer of bricks behind the exterior layer. This layer holds the lintel bricks in place and has to be removed to fix them. Note: Save these bricks and clean them for reuse later.
3. Inspect the existing framework behind the second wythe. If it needs to be repaired, do so now by removing the old nailer and replacing it with a new piece of 2×4 pressure-treated board cut to length. Install a piece of butyl flashing against the nailer and window casing for waterproofing.
4. Replace the second wythe of brick starting on top of the new nailer (or existing nailer if it didn’t need repair). For the bottom-most course, only place mortar on the heads of the bricks, not underneath. These bricks should lay directly against the nailer. Use bed joints and head joints above this course. Cover this layer of brick with a facing of mortar for waterproofing and strength.
5. Install another piece of butyl flashing by pressing it into the joints above the repair second wythe and pressing it down into the facing of mortar. Use a pointing trowel to pack mortar in the joint above.
6. Once the second wythe is installed and flashed, install a piece of steel angle iron across the brick to provide a strong, durable lintel.
7. Create a mixture of restoration sand, portland cement, and lime that matches the existing mortar. Use a chunk of the old mortar for comparison. Adjust as necessary before adding water to the mix, achieving an oatmeal consistency.
8. Install the first layer of brick onto the lintel using the lip stretcher bricks. Do not use a bed joint, as this can cause corrosion and cracking. Simply use a head joint to install the bricks. Once the first course is installed, use head and bed joints to install the courses above.
9. Dress the joints between the bricks with the appropriate trowels to mimic the existing mortar for a seamless look. Brush the surface to clean off any excess dust and mortar and then use a damp sponge to blend the repair.

Resources

To protect the window, remove the shutters and cover the window with plywood.

To break the mortar, use a chisel and hammer. Remove the loose brick and continue to chip away the old mortar. You can use a mill file to remove stubborn mortar.

To prevent water penetration, apply flashing before adding back the brick.

To add structural support, Mark incorporates a steel angle iron. Mark uses a grinder to hollow out brick. The hollowed bricks are called lip stretchers. The overhang of the brick covers and disguises the steel angle iron.

To match the mortar, Mark uses a fixture of restoration sand, Portland cement, and lime. Mark suggests using a piece of the old mortar to compare as you’re mixing. Use a trowel to slowly mix the material with water.

Apply mortar only to the head joints when adding back the brick.

Use a damp sponge blend the new mortar with the existing mortar.

Materials

• Plywood
• 2×4 pressure-treated boards
• Butyl flashing
• Steel angle iron
• Restoration sand
• Lime
• Portland cement
• Lip stretcher bricks

Tools