|
|
Installation of Paving Stones by Bill
Prudehome
Because
the installation of concrete paving stones is a
complex and time consuming procedure many do it yourselfers do not
invest in
the effort to do the job right - the first time. If proper installation
is not
followed, the pavers will heave in some spots, settle in others and
spread out
producing an unsightly outcome.
The following
information is intended as an overview to the proper
installation of concrete paving bricks. These are the steps that would
be taken
by a reputable contractor who would be providing a guarantee on the
work done.
- The first and a very
important step is to have the property surveyed for buried cables,
power lines and gas pipes before you start digging. Most utility
companies provide location services free of charge. All it takes is a
phone call. If you excavate without having the location services flag
your property, you will be held responsible for any damages and
subsequent repairs. Not to mention the fact that cutting into a buried
electrical service with a shovel could put you out of commission for a
very long time. As well, think of the anguish you might create in the
community by cutting off utility services to your neighbors. The
primary service companies that should be called are gas, electric,
cable TV, and telephone.
- Using stakes
and string map
out the area to be excavated. The more intricate the area, the more
complex the installation and cutting of the paving stones. Remember
that paving stones are not flexible and hence tight curves and arches
can be difficult to fill.
- Remove the existing
pavement, sod, plants, and trees from the area to be excavated.
- Excavate the soil to the
required depth. The depth needed is the basic calculation derived from
taking the finished surface minus the thickness of the paver, the depth
of the setting bed and the depth of the base material. The required
thickness of the base material (commonly 4 to 8-inches for patios and
walkways and 6 to 12-inches for driveways and roadways) is totally
dependent on local soil conditions, primarily the soils reaction to
water. The city or county soil engineer will be able to tell
you the required thickness of the base material for your area.
- Prior to
laying the base
material, the sub-grade must be compacted. With a clay sub-grade you
will need to use a powered roller or rammer. With a sandy soil the use
of a mechanical vibrator, should be adequate to provide proper
compaction.
- After the sub-grade is
compacted, place a layer of landscape (geotextile) fabric on the
sub-grade. It is important that the base material be somewhat isolated
from the natural soil, especially in high moisture areas.
- Use a granular base material
that compacts easily on top of the landscaping fabric. The material
should be laid in 2 to 4-inch layers, or lifts as it they are called
within the industry, with each layer being individually compacted. It
is impossible to get proper compaction in a layer that is thicker than
4-inches no matter what type of compacting equipment is employed. The
base material goes under numerous names ("type 2 base", "AB3", "21A" or
"3/4 minus") depending on where you are located. Your local concrete
paver supplier will know the material to be used as a base for
installing the pavers.
- Once the granular base
material has been compacted, install edge restraints along the border,
on top of the base material using steel spikes to secure them in place.
The edge restraints are a key part of the potential longevity of the
paver installation as they provide lateral load resistance and provide
continuity to the interlocking characteristics of the paving stones.
Without the edge restraints, the paving stones will separate and spread
over time.
- Lay the setting bed, to a
depth of 1 to 1.5-inches, on top of the compacted base material and
spread it evenly across the entire project area. The setting bed is
usually a material of washed coarse concrete sand or granite stone
dust.
- You are now ready to install
the pavers in your chosen pattern. As a general statement, it is best
to start at one end of the project and in the middle of the area (there
are some exceptions with complex patterns. Do not place edge pavers
first as you cannot be sure of their precise location. If it is a large
project and you have several skids, take pavers randomly from all skids
to ensure that any color variations between the individual skids are
blended within the total project.
- The paving stones are down,
but you are not quite finished! Sweep sand over the top of the pavers
and fill the gaps between the pavers. Use a vibrating compactor, over
the entire project, to force the sand to completely fill the gaps
between pavers (sweep additional sand as necessary). The process of
vibrating sand into the gaps creates an amazingly solid and stable
surface.
- Last but not least, remove
any excess sand that has accumulated from the previous step and apply a
protective sealing finish to your project. A sealer will highlight the
paver colors and protect the stones from staining. The sealer should be
applied at regular intervals, follow the manufacturer's instructions.
Tip 1: If it rains
during the compacting phases of the sub-grade or the base
material, make sure that the ground has dried out completely before you
continue.
Tip 2: Remember
drainage when grading the soil. You should allow for a slope
of 0.25-inch per foot to allow water to run off the finished project.
Tip 3: Don't be
afraid to use a level during all phases.
As with all home
improvement and landscaping projects, planning and
knowledge are the keys to success.
For additional
information on pavers, landscaping or other home improvement
projects, visit Renovation
Headquarters
About the Author
Bill Prudehome has more than 25 years experience in home
improvement,
remodeling and landscaping. Through his website - Renovation-Headquarters.com
he provides a wealth of information on all aspects of home improvement,
remodeling
and landscaping.
|