Page 304 - Masonry and Concrete

Paving

303
PAVING

must be provided in rigid masonry paving to accommodate thermal
and moisture movements. Joints should generally be located parallel
to curbs and edges, at 90° turns and angles, and around interruptions
in the paving surface (Figure 8-26). Fillers for brick masonry expan-
sion joints must be compressible to accommodate the natural expan-
sion of brick units as they absorb moisture (Figure 8-27).
Clean the top of the concrete slab and apply the mortar setting bed.
This setting bed will not only hold the pavers in place, but it will also
help to compensate for minor irregularities in the slab surface. If you
are working on an existing slab and it is not properly sloped to drain
water, you can use the mortar setting bed to achieve some drainage.
3
Maintain a minimum thickness of 8 in. and a maximum thickness of
1 in. Place the mortar, then smooth the surface using the flat side and
score the surface using the notched edge of a metal trowel. Place the
pavers and mortar joints in one of three ways.

■ Using a conventional mason’s trowel, butter two sides of each
paver and set them firmly into the mortar setting bed. If neces-
sary, tap the pavers down with the trowel handle and use a
mason’s level to check the surface to make sure it is level.
Remove excess surface mortar with the edge of the trowel.

■ Place the units on the mortar setting bed, leaving the joints open.
After the pavers have been installed and set up for a day or two,
wet them with a garden hose and fill the joints with a thin mortar
mix about the consistency of sour cream. Use a coffee can or other
small container that can be squeezed to form a spout, and work
the mortar into the joints with the point of a trowel. Use a wet
sponge or cloth to clean excess mortar off the brick surfaces
before it dries.
■ Instead of the usual mortar setting bed, lay the units on a cushion
of 1 part portland cement and 3 to 6 parts damp, loose sand. Leave
the joints open, spacing the units apart with your finger. After all
the pavers are in place, sweep the open joints full of the same dry
portland cement and sand mixture. Be careful, especially at first,
not to dislodge the pavers as you sweep. Sweep excess material
from the surface and spray the paving with a fine water mist until
the joints are completely saturated. Keep the paving moist for at
least three days to assure proper curing of the cement.

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