[apologies, this thread slipped out of my display "window" -- out of sight...]

On 10/3/2015 2:45 AM, dadiOH wrote:
Don Y wrote:
~1980 house is built of stucco over cinder block (in some places) and
slump block (in others).

There are long, narrow, noticeable cracks in the exterior stucco
suggesting some subsidence (water is all ground sourced, here). Neighbors
suggest "just slather some paint over it". frown

Is it OK to just patch these cracks? Or, should we expose the
underlying blocks to get an idea as to how much they've penetrated
the structural block?

If *just* superficial, any advantage to polymeric patches vs. (cement)
"stucco patch"?

And, if the cracks permeate the underlying block (presumably on mortar
lines), what's the recommended remedy? Anything "injectable"?
(fine mortar, cement adhesive, etc.)

Since the cracks are there because of movement, I would not use a
cementatious material to patch them.

Why? What do you see as the downside? If the building is still "settling",
wouldn't any new mortar lines open themselves under the continued strain?

I.e., how would such a repair differ from the way it *was*? Or, the
way the rest of the joints that *haven't slipped?

I want something that allows for a bit
of movement. I caulk and paint them.

So, you only deal with the cosmetic aspect of the stucco (surface)
and don't sweat any structural consequences?

For hairline up to maybe 1/8 I use
acrylic caulk, I had a joint between a free standing wall and the house
that had opened up to 1/4 - 1/2, used polyurethane caulk.

We have a similar issue with a wall that adjoins the house and supports
the back/side gate. The closing of the gate inevitably causes the wall to
"move" wrt the house, opening a large crack. I plan on sinking some
bolts into the house and tying the wall to them. Then, fill with mortar.

The norm IME for stucco cracks is on block joint lines, easily visible. I

Yes. Very apparent (for masonry homes). Stucco on wood frame seems to
generate arbitrary cracks -- typically more vertical than running
along horizontal mortar lines as with block.

haven't worried about whether the cracks penetrate into the block joints as
there is nothing I could do to repair same without major effort and expense
and I view some joint cracks rather the same way as I would in wood; i.e.,
minor local damage does not impair the whole.

I was considering opening the stucco and seeing if there was a substance
that could be "squirted" into any cracks in the mortar lines. Then,
repairing the stucco (house is due to be painted, hence the reason
for addressing it now)