Page 284 - Masonry and Concrete

Paving

283
PAVING

the size, style, and design of the house. Sidewalks should be 4 in. thick
1
and sloped 4 in. per foot to drain water off the surface. Sidewalks are
typically supported on a 2-in.-thick sand bed over the subgrade.
The proportions of riser height and tread depth affect how easy or
how difficult steps are to climb. There are some basic rules of thumb to
follow. The height of two risers plus the depth of one tread should add
up to 25 in. or less. The lower the riser, the deeper the tread should be,
and vice versa. Many building codes prescribe a maximum riser height
1
3
of 7- 2 or 7- 4 in. and a minimum tread depth of 10 in. Lower risers are
easier to climb, particularly for the elderly or disabled, and steps with
low risers and deep treads are also more gracious than those with steep
risers and narrow treads. For flights of steps less than 30 in. high, a
good riser height is 7 in. with an 11-in. tread. For flights of steps with a
total rise of more than 30 in., individual risers should be about 6 in.,
with a 12-in. tread. A 5-in. riser and 14-in. tread combination is very
comfortable to climb and can make steep grade changes easier to nego-
tiate. A 1-in. nosing can be added to the tread depth as shown in Figure

10'-0" MIN.

1 1 /4"

CROWN

REINFORCING
MESH
1 1 /4"

INVERTED CROWN

2 1 /2"

CROSS-SLOPE
FIGURE 8-4
Slope to drain rain and melted snow.

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