Page 196 - Masonry and Concrete

Footings, Foundation Walls, Basements, and Slabs
195
FOOTINGS, FOUNDATION WALLS, BASEMENTS, AND SLABS

6.2.3 Footings Without Forms

For shallow footings in firm soil, wood forms can be eliminated and
the concrete formed by the earth trench itself. The trench should be
the exact width of the footing, excavated using a square-nosed
shovel to keep the edges straight. The trench should be deep enough
that the bottom of the footing will be at least 12 in. below grade as
required by Code (Figure 6-10). A row of wooden stakes or short
reinforcing bar lengths driven into the ground down the middle is
used to indicate the required thickness of the concrete. A straight 2
4 and a level can be used to make sure the tops of the guide stakes
are level. When the concrete is poured, simply strike and float the
surface even with the tops of the stakes and then remove them. A

FORM
SPREADER
KEYWAY
SOIL PRESSURE PREVENTS
SLIDING

FIGURE 6-7
Footing spreaders and keyways. (from Portland Cement Association, The Homeowner’s
Guide to Building with Concrete, Brick and Stone, PCA, Skokie, Illinois).

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