There are several considerations in installing a lintel in an existing brick wall.
How to install a concrete lintel in an existing wall.
The practice of propping a lintel is sometimes used to facilitate speed of construction.
Wedge the beam into the opening then pack any gaps with masonry mortar.
The beam will distribute the weight of the wall s load to either side of the door opening.
It should only be introduced after initial masonry load has been applied to the lintel.
Steel lintels in concrete block walls are placed in the mortar between blocks so the first step will be opening a space for the lintel itself.
By far the quickest way to form an opening through a non load bearing wall is to mark your opening and cut the width right up to the ceiling then mark out for your lintel and insert it at the correct height cutting it into the sides of the wall 6 inches either side for its bearing.
Final part of guide how to install concrete lintel.
Install the steel lintel above the door.
If you plan to cut a hole in a brick wall you will have to install a lintel a flat steel beam to ensure that the brick wall does not fall down.
For example you need to consider the weight or the load which the lintel will have to carry.
With the intended position of the lintel marked on the wall carefully use an angle grinder or masonry saw to cut away the mortar.
When propping a lintel a horizontal timber plank should be placed along the underside of the lintel and suitable props secured into place at maximum 1200mm centres.