When a lintel, the horizontal support beam above a window or door in a brick wall, becomes damaged or fails, it can lead to serious structural issues if not repaired promptly. Lintels made of brick, steel, or concrete can crack, sag, or rust over time, causing the bricks above to shift and the wall to potentially collapse. Replacing a lintel is a complex project that requires carefully removing bricks, installing temporary supports, and rebuilding the wall. Here is a step-by-step guide on how to properly replace a damaged lintel in a brick wall.
Assess the Damage and Prepare the Work Area
The first step is to carefully inspect the lintel and surrounding brickwork to determine the extent of the damage. Look for cracks, sagging, or signs of rust. If the lintel is severely damaged, it will need to be replaced. If it is only slightly damaged, it may be possible to repair it using helical bars or other reinforcement methods.
Once you have determined that the lintel needs to be replaced, prepare the work area by removing any shutters or window coverings and covering the window with plywood to protect it from debris. Set up scaffolding or ladders to provide safe access to the work area.
Cut into the Mortar and Remove Bricks
Using a chisel and hammer, carefully cut into the mortar between the bricks above the lintel. Work slowly and carefully to avoid damaging the bricks. Remove the loose bricks and continue chipping away at the mortar until you have exposed the lintel and the bricks behind it (the “second wythe”).
Use a grinder to hollow out some of the bricks above the lintel to create “lip stretchers” that will help conceal the new lintel. These bricks will have a lip that overhangs the lintel, hiding it from view.
Install Temporary Supports
Before removing the lintel, install temporary supports to hold up the bricks above. This can be done using acrow props, strong boys, or trestle scaffolding. Make sure the supports are securely in place and can bear the weight of the wall above.
Remove the Old Lintel
Once the temporary supports are in place, carefully remove the old lintel. If it is made of steel, you may need to use a grinder to cut through it. If it is made of brick or concrete, you may need to break it into smaller pieces using a sledgehammer or jackhammer.
Remove any old mortar or debris from the area where the new lintel will be installed. Clean the bricks thoroughly to ensure a good bond with the new mortar.
Install the New Lintel
Choose a new lintel that is appropriate for the size of the opening and the weight of the wall above. Steel lintels are strong and durable, while brick or concrete lintels may be more aesthetically pleasing. Install the new lintel on a bed of mortar, making sure it is level and securely in place.
If using a steel lintel, you may need to create a “lip stretcher” brick course above it to conceal it from view. These bricks will have a lip that overhangs the lintel, hiding it from sight.
Rebuild the Wall
Once the new lintel is in place, begin rebuilding the wall above it. Use the bricks you removed earlier, or new bricks that match the existing ones. Apply mortar to the head joints (the vertical joints between bricks) and the bed joints (the horizontal joints) as you lay each course of bricks.
Make sure to stagger the vertical joints between courses for added strength. Use a pointing trowel to apply mortar to the joints between the new brickwork and the existing wall.
Finish and Clean Up
Once the wall is rebuilt, remove the temporary supports and clean up any debris. Use a wire brush to add texture to the new mortar joints and make them blend in with the existing ones. Apply a damp sponge to the surface of the brickwork to remove any excess mortar and create a smooth finish.
Allow the mortar to cure for at least 24 hours before removing the plywood from the window. Check the wall for any cracks or gaps and repair them as needed.
Replacing a lintel in a brick wall is a complex and challenging project that requires careful planning, preparation, and execution. It is important to assess the damage accurately, use appropriate tools and materials, and follow safety precautions at all times. With the right knowledge and skills, however, it is possible to replace a damaged lintel and restore the structural integrity and appearance of a brick wall.