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Holding
back mountains of earth or creating a small raised garden bed, looking
good all the while is what retaining walls were born to do. Our
professionals are seasoned installers of segmental retaining wall units
(like Versa-Lok or County Block), fieldstone boulders, and split-faced
limestone. We also install timber retaining walls,
if that is what your project needs. No matter the height of the wall or the materials being
used, we can build a retaining wall that will resist the forces of time
and nature for years to come.
Two keys to the
successful installation of a long-standing retaining wall are base
preparation and  reducing hydrostatic pressure. When our installers begin
a segmental retaining wall project, we excavate to a depth that allows
for a crushed stone base that's 6 inches deep, and allows for the
embedment of the appropriate number of wall courses. This embedment
locks the 'foot' of the wall into the soil around it, helping to prevent
movement.
Equally important to a
stable wall is drainage. Buildup of hydrostatic pressure is the main
killer of retaining walls. Rainwater tends to collect in the soils
behind a retaining wall. If that water is not given a path to drain from
behind the wall, it will begin to push on the wall. Water is heavier
than soil, and pressure during summer months can harm the wall. But
during the late fall and very early spring, when the temperature
fluctuates around freezing every day, the greatest wall damage is done.
During those times, water can flow behind the wall, where it will freeze
overnight, expanding just a little. And pushing the wall outward just a
little. That freeze-thaw cycle continues, millimeter by millimeter,
until the wall has been pushed completely over. That's why a system has
to be in place to collect the water and get it out from behind the wall
as quickly and efficiently as possible. To see a diagram of how we do
this, click here.
Once wall heights
exceed 4', it becomes necessary to consider the use of geogrids to
anchor the wall further. A geogrid is a woven material that is placed
between courses of retaining wall block and extends into the soil behind
the wall. This grid helps to anchor the wall to the very soil it
retains, making the wall and the soil one very large retention
structure.
All of our retaining
walls are mortarless, or 'dry laid' walls. Mortar is a very hard stiff
material that has no flexibility in it. It is this inflexibility that
harms the wall it is used with. Soil will apply pressure to every wall.
Those walls that are incapable of flexing to soil pressures will crack
and fail. Further, the mortar helps seal off the back side of the wall,
further increasing hydrostatic pressure on the wall. A dry laid wall has
natural points between blocks or stones where water can 'weep' from
behind the wall. And without mortar, the wall units can flex to absorb
the pressure of soils,without diminishing the strength of the wall. We
are so confident that the walls we build are made to last that we offer
a two-year guarantee on them.
Our professional staff
receives ongoing training to keep current with the best techniques for
installation of retaining wall projects large and small. If you have a
bed that needs raising or a mountain of earth that needs retention, we
can build an attractive retaining wall. Click here if you'd like to see more pictures
of our wall work.
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