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Paving Brick installation Process
Paving Brick Basics
There are two types of
installations; vehicle traffic and non-vehicle traffic. The
installation process is very similar for both types. We will cover
both in these instructions. You will first need to understand the
materials and amounts needed before work can begin. Paving brick is
installed in layers.
- Base Stone - is the
layer that provides the strength and flatness of the paving
brick surface. Spend lots of time on this layer, it will pay
dividends later in the installation process. We recommend you
use a stone product called 'Crusher run'. It is crushed
limestone blended with decreasing sizes of limestone. This
product has sharp angular edges that compacts well. The size of
crusher run will depend on how much weight the surface is to
bear. Most side walks and patios require 5/8 inch crusher run,
also referred to as 'Driveway mix'. Driveways will require 2"
Crusher run. Your
excavation depths will depend on soil type and whether the
paving brick project is for vehicle traffic or non-vehicle
traffic. Assuming you have good sub-soil, projects for
non-vehicle traffic will require between 4 to 6 inches of base
stone for vehicle traffic, you will need between 8 to 15 inches
of base stone. Again, there is a big variation of the depth of
base stone because there are many factors that have to be
examined to determine how much you will need.
- Bedding Sand - The
sand performs two important functions. The first is that it
provides a cushion for the paving brick. The second is that it
holds the brick joint sand from washing out. This is the least
expensive part of the whole installation and it causes so much
trouble when the wrong sand or too much sand is used. It doesn't
matter whether your project is for non-vehicle traffic or not,
you will want to screed a uniform 1 inch layer of sand over the
stone base. This layer does not get compacted until after the
brick is placed over it. As mentioned before, the type of sand
is very important. Do not use play sand, mason sand, or sand box
sand. The sand must have the same properties as the stone base,
sharp angular edges and decreasing smaller particle sizes. The
top particle size is rather large, about 1/8 inch in diameter.
The reason is that you want the sand base to compress uniformly
across the entire surface area. The use of other sand material
does not compress uniformly and will cause a wavy surface in
time. The sand bed is the weakest layer in the whole
installation and the deeper you go with sand the weaker that
layer becomes. Edge restraints are designed for a sand depth of
1 inch.
- Paving Brick - This
layer is pretty simple but there are a few things to mention
about the brick layer. Standard pavers are ( 2 3/8" ) 60 mm
thick. This is suitable for sidewalks, driveways, and light use
parking lots. Most paving brick styles now have joint spacers on
the sides. Place the brick tight together and it will leave a
sand joint of about 1/16 inch.
- Edge Restraint - The
use of a good commercial edge restraint is critical to a strong
and long lasting paving brick project. The edge restraint gets
installed around the perimeter of the brick area that does not
butt up against a hard surface such as a driveway, sidewalk, or
foundation. The job of the edge restraint is to keep the brick
from moving laterally and having the brick joints spread apart.
When this happens, the interlock fails and the whole surface
area starts to fail. The edge restraint gets installed directly
on the stone base. Pull away any excess bedding sand before
installing the edge restraint. Drive in anchor pins a minimum of
1 foot apart to anchor the edge restraint. Remember, these
commercial edge restraints are designed to be invisible, meaning
you will back fill over them with top soil or mulch to hide it.
- Sand Joint - The kind
of sand you use for the joints will determine how well you will
create the lock-up and how much time and labor goes into filling
the joints completely. Joints that are not completely filled not
only are the cause of a weak lock-up but also the reason grass
or weeds infiltrate the sand joints. Stores that sell paving
brick also carry bagged dry joint sand. If the sand is wet, you
can not work it into the joints and it takes much longer to fill
all the joints.
Steps to Installing Pavers
1) Excavation
Before you put a shovel into the
ground, you should check for underground utilities. You must
excavate a minimum of 6 inches. Excavate 1 foot when possible,
beyond the finished edge of your brick area on all sides that do not
butt up against hard surfaces, such as; asphalt, concrete, or
foundations. This is done to allow for the edge restraint to be
installed later. When digging, do not dig deeper than necessary.
Your goal is to leave the sub-base untouched. If you do disturb the
sub-base, run a plate tamper over it before filling with the stone.
Your excavation depth will depend on what type of paving brick
project you are building. For non-vehicle surfaces, allow 4 inches
for the stone base, 1 inch for the sand bed, 2 3/8 inches for your
pavers that equals 7 3/8 inches deep. Your sand bed will compress
about 1/4 to 5/16 inches after compaction so you will want to dig
about 7 1/4 inches deep.
2) Base Installation
Place the crusher run stone and
compact in layers no more than 4 inches deep. The stone base is the
layer that determines the contour and slope of the paving brick
surface. You do not use the sand bed to determine the grade or
slope. The sand bed and pavers will follow the contour that you
create in the base. If your base stone surface has valleys and high
spots, these will show up later in the brick surface. Allow 1/8 to
1/4 inch slope per foot for drainage. Make sure that you compact the
stone base thoroughly, paying special attention to the outside
edges. A poorly compacted base will allow the pavers to move and
settle. Do not rush through the base installation. This is the
foundation of your paving brick surface and the time spent here will
reward you with a quality installation.
3) Bedding Sand
The bedding sand gets screeded in
a layer 1 inch deep. To achieve this, use two pipes that measure 1
inch in outside diameter. I like to use black iron pipe for this, it
is rigid and inexpensive to buy at your local hardware store. Lay
the two pipes parallel to each other and place bedding sand across
them, then pull a straight 2 x 4 across the top of the pipes. You do
not need to screed the whole paver area before placing bricks, you
can screed in sections. It is best to keep the moisture in the sand
by covering your sand pile with a tarp or plastic sheeting when it
is delivered to you. If your sand dries out, you can spray it with a
garden hose to remoisten it. The bedding sand will get compacted in
the last step of installation. Do not walk on the sand bed. After
you have screeded across the pipes, lift the pipes out of the sand
bed and fill in the groove left by the pipes and smooth over with a
cement trowel. Make sure to screed out beyond the finish edge of
where the brick will end.
4) Placing Paving Bricks
Stretch a mason line or snap
a chalk line in the sand bed to start from. Place the pavers along
this starting line in the pattern that you choose. Set the pavers on
the sand, but don't hammer them into place. There should be a slight
gap between the pavers. As you work, stay on top of the pavers, not
on the sand. Every 2 or 3 feet, set a string line and check both
line and alignment as you go. Use a rubber mallet or dead-blow
hammer to adjust the alignment. When you can't place a paver because
it needs to be cut, leave it out, only place full pavers for now.
After placing all the pavers make the cuts and place them. Now
inspect the entire surface for chipped or defective pavers and
replace any that you find. Check your lines and adjust using your
mallet or a large screw driver.
5) Installing Edge Restraints
Use a square point shovel or
cement trowel to cut down along the outside edge of the pavers down
to the stone base and pull away the excess sand away from the
pavers. Being careful not to cut into the stone base. After you have
removed the excess sand, place the edge restraint up against the
pavers, right on top of the stone base. Drive the anchor pins in 1
foot apart for non-vehicle surfaces and 6 to 8 inches apart for
vehicle traffic.
6) Compacting Pavers & Sanding
Joints
There are two methods to
compacting and sanding that you can use. The first one is to spread
dry joint sand over the surface and sweep in to fill the joints.
Then run the plate compactor over the paver surface first in one
direction then perpendicular to the first one. Run the plate tamper
over the surface until you have filled the brick joints completely
to the top. Wet sand will not vibrate into the joints so make sure
the brick surface is dry before attempting to place sand. The other
method is to run the plate tamper over the surface before sanding
the joints. After running the plate tamper over the surface in two
directions, sweep the joint sand into the joints. Run the plate
tamper over the surface again. I like to use this method because it
does a better job of leveling the brick surface and I also feel it
does a better job of locking up the pavers. When you are done
compacting, sweep off the excess sand, I like to leave a little sand
on the surface to let Mother Nature work in any places that I have
missed. You can also mist the surface with a light spray from your
garden hose. The goal is to completely fill the sand joints to the
top, this is important to the strength of the project and to keeping
your brick joints weed free. After the first winter you will find
the the sand joints have settled, all you have to do is sweep in
more joint sand to fill them back up to the top.
7) Clean Up & Final Inspection
Inspect the surface for bricks
that might have been chipped or cracked in the compacting step. If
you find any, replace with good ones and re-sand. Back-fill over the
edge restraint with soil or mulch. The last thing to do now is sit
back and admire your work.
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