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
cement.

Without being physically anchored, I expect this to eventually slide
out, just as the last repair did, but it might last longer.
Might not.

Any other suggestions?

Thanks in advance.

wrote:
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
cement.

Without being physically anchored, I expect this to eventually slide
out, just as the last repair did, but it might last longer.
Might not.

Any other suggestions?

Thanks in advance.

if its not structural just cover with a wood or other item TRIM and
paint whatever color you prefer.

such dissimiliar items will always move around, trim letys it move
without causing grief

attach trim to either building OR steps but NOT BOTH! soi stuff can
moive