You have not had much response to your question. Engineering will help
prevent roll over. If you are going to do your own anyway, I would suggest
that you make the footing wider. A typical minimum would be twice the wall
thickness, as a retainer, it could easily need more. It would be usual to
keep more of the footing under the hill. Drainage is critical as
hydrostatic pressure behind the wall will push it over Residential footings
require 2 #5 bars. I would think you need a tied mat with your hook bars
coming up in the block cells. I would suggest 4' o.c. as an absolute
minimum.

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DanG


"chibiabos" wrote in message
...
Building a cinder block retaining wall, three feet high, 24 feet long.
Been a while since I did any masonry but I remember the basics and
helped my neighbor build his a few months ago. In fact, this wall will
tie off an end of one of his runs. Block is 8x8x16 plain cinder, will
be filled solid and have a stucco skimcoat. Wall will hold back a 2.5
foot wide strip of sandy soil between a sidewalk and my neighbor's
block wall. Has good drainage.

My question regards the footing. I'm on the California coast, so
there's no freezing; no frost line to consider. Below-grade soil is
hard, virgin rotted sandstone. The footing will be concrete, 12" wide,
8" thick, buried 6" or so below grade.

What number of pieces of 1/2" rebar is recommended for this type of
footing under this kind of wall? Is two enough? I plan to bend one or
more pieces of rebar up at 90 degree angles along every four to six
feet of the wall to a height of 30" or so, and slide blocks down over
them, then fill and cap all blocks with solid concrete, plus generous
placement of masonry ties during construction.

Any useful thoughts and advice is highly appreciated.

-chib

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