Remove loose material from the hole in the wall by probing it with the tip of a screwdriver or blade of a putty knife.
Opening hole in concrete wall.
You want the concrete surface in each hole to be perfectly clean.
Until now i just figured they weren t ready to knock it out.
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.
With the intended position of the lintel marked on the wall carefully use an angle grinder or masonry saw to cut away the mortar.
Anyway the landord was adding an overhead door for the next tenant and the concrete cutters came in one morning anchored tracks to the wall and ran the rail saws in about 8 hours they had a 12 ft overhead door cut but like above left the concrete in the hole.
Correct placement of the rebar helps prevent the concrete around openings from cracking from structural loads or shrinkage.
Drill through each corner of your cutout using a rotary hammer equipped with a masonry bit.
Steel reinforcing bar around openings is a critical structural element of cast in place concrete walls whether they are built with removable forms or insulating concrete forms icfs.
These holes will mark the boundaries of the opening and help guide your cuts.