I have two adjacent single internal doors in a block wall (load bearing) which are being converted into a double door. Between the existing doors is a central 7" wide pillar. One door has a 7" high concrete lintel across the door to the central pillar. The other has a wooden 6" lintel to the central pillar. The gap above the shallower wooden lintel has been filled with an assortment of ceramic tile and offcuts of wood mixed in with mortar. The structural engineer specified the new lintel to be either concrete minimum 150mm or box 100 standard loading steel lintel (which at 2100mm length is also 150mm high). My question is when installing the new 150mm tall lintel into the gap currently occupied by 7" (175mm) lintel how i deal with the additional 25mm gap. What is the correct thing to do ?. I am assuming that it would not be right practice to put in additional 25mm depth of mortar over either the supporting wall ends or between the top of the new lintel and the existing block above it ? and if this is not correct what would be the best material to use to fill this 25mm gap ? any help with this well appreciated.
Rgds
Steve C.
Rgds
Steve C.