Page 293 - Masonry and Concrete

Paving

292 CHAPTER EIGHT

WEDGES
SCRAP LUMBER 2 6
2 4 AT ENDS

SIDE FORMS
CROWN

2 6 2 4 WEDGE AT CENTER

TOP OF
STAKE
INVERTED CROWN
LOWER
THAN FORM
TO ALLOW
SCREEDING
FIGURE 8-14

Sloped strikeoff board.

sion of the reinforcement. Some authorities also believe that a sand bed
helps the concrete cure more evenly. The sand should be leveled to a 2-
in. uniform thickness using two 2- -4’s nailed together so that one will
slide along the top of the form boards and the other will drag the sand
1
1
surface (Figure 8-15). Sidewalks on flat ground often slope 8 to 4 in.
per foot from one side to the other to drain water. Calculate the amount
of slope needed for the width, and set the string on one side lower by
1
that amount. For example, a 3-ft. sidewalk sloped 8 in. per foot should
3
3
be 8 in. lower on one side than the other, so the string should be set 8
in. lower. Set the forms so that the tops of the boards align with the
string (Figure 8-16). The depth of the sand bed should vary so that the
concrete will be a uniform 4 in. thick. On the low side, the sand should
1
be a minimum of 1- 2 in. thick. Once the forms are set correctly for the
slope, the sand can be struck to the same slope using the method
described above with two 2- -4s nailed together so that one will slide
along the top of the form boards and the other will drag the sand surface.

8.2.3 Steps
Concrete steps provide a durable and low-maintenance approach to a
porch or patio and can be used in conjunction with either concrete or

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