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DESIGNING THE STEPS:
These dimensional guidelines should be followed for safety reasons:
1. Height of each step ("riser") should be the
same ( 6 to 8 inches).
2. Depth of each step ("tread") should also remain
constant (10 to 12 inches).
3. If step is to serve as a "landing," it should
be at least 3 feet deep.
PREPARING THE BASE:
Level all ground in front of door. Remove all grass roots and
other organic matter from the surface. Dig to a depth of 6 inches.
Use sand, gravel or other fill (4 inches maximum) to bring site
to a uniform grade. Compact the fill by dampening, then tamping.
Base should be uniform, hard and free from foreign matter.
BUILDING THE FORMS:
Use 1/2-inch sheets of plywood for the side forms. Cut according
to step dimensions desired. When designing forms, allow extra depth
for fill bellow ground level. Drive 2" X 4" stakes, allowing
a half inch between stakes and intended side of steps, thus providing
space for plywood form. Use a level to keep side forms perfectly
vertical. Nail side forms to stakes and brace all stakes with additional
2" X 4"'s. If steps are to abut house or other foundation,
apply a half-inch mastic expansion joint. Coat all inside surfaces
of forms with oil. This eases removal.
POURING THE CONCRETE:
It is important to mix and pour entire project at one time,
thus producing a solid integral mass.
To determine the amount of concrete necessary, measure
each step as an 8-inch slab. Overfill forms slightly. Work a shovel
in and out to eliminate air pockets, and to compact the mix. Solid
rubble such as broken block or brick may be worked in, reducing
the amount of concrete mix required. Work the mix in and around
all rubble thoroughly.
FINISHING AND SMOOTHING THE SURFACE:
After spreading and compacting the mix to fill the
forms, "strike off" and float immediately. To "strike
off," simply nose the edge of a 2" X 4" back and
forth with a saw-like motion to smooth the concrete. Then use a
"darby" (smooth board 3-1/2 inches wide and 3 feet long
with a handle on top) to level ridges and fill voids. These two
procedures help embed all particles of coarse stone or gravel slightly
below the surface. Wait until all water has evaporated from surface
before final smoothing or troweling. When surface has turned dull,
use edging tool to round the edges. An edger with a 1/2" radius
is recommended. The remaining concrete should be completely smoothed
and compacted by troweling. For best results keep the trowel pressed
flat, sweeping back and forth in an arc, each pass overlapping half
of the previous pass. Excellent results can be attained by using
a steel trowel that measures approximately 4" X 14". To
produce a textured non-skid surface, use a wood float for final
troweling.
CURING:
Proper curing of all cement mixes is necessary for maximum strength
to be achieved. Concrete which has been moist-cured will be approximately
50% stronger than that exposed to dry air. Concrete reaches 98%
of its strength in 28 days. Keep concrete damp for a period of 5
to 7 days after it has been poured. This helps the hardening (hydrating)
process, thus producing a more durable surface. After concrete has
cured remove forms
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