A long time ago some precast concrete stairs were put in place up
against a concrete area (band) of the brick building. The filler
material has given way, and there's a 1 to 2-1/2 in gap between the
steps and the building. The only bridging material anyone can recall
was a hunk of pipe insulation wedged in there and covered with an inch
or so of patching concrete(!). You can go under the stairs to a
basement apartment, so just brute-force filling the crack with concrete
up against a joint filler won't work unless there's a way to keep
everything from just falling through. The underside of the stairs has
a corrugated look (big corrugations: 3 in wide (or so) recesses and
protrusioons that extend a few inches), and the side next to the
building is the last recessed area, so there's a depth of just about
3-4" from the top of the top step, to the bottom of the underside here.
My thought was to glue a 3/4" joint filler to the building, make a
long, thin, shallow trough out of something like hardware cloth and put
it between the filler and the stairs, and fill that with an anchoring
Without being physically anchored, I expect this to eventually slide
out, just as the last repair did, but it might last longer.
Any other suggestions?
Thanks in advance.