MARKING OUT THE CONSTRUCTION
Establish the location where the fire pit is to be built. Mark the
center of that location. Then drive a stake into the ground or
hold a pin at the center point of that location. If you are building
your fire pit on a concrete slab or paver surface, tether a line
24″ or slightly longer to that center point with a marking device
tied at the opposite end and follow directions under Step #1.
If you are building your fire pit in an open area on the ground,
your excavation and compacted stone base needs to exceed
the exterior circumference of the fire pit by 6″ on all sides, so
you will need a line that is 30″ or longer. Follow directions
under Step #2. Carefully swing the marking device around
the center point keeping it vertically aligned and mark out the
circular exterior dimension of the fire pit construction. If you
are constructing the fire pit on a solid surface that will remain
exposed, do not use a permanent marker.
STARTING CONSTRUCTION
When building the fire pit wall, arrange the first course of
tapered fire pit wall block in a circle, making sure that all of
the units are fitted tightly together. Orient all of the blocks so
that the narrow vertical face of the block is on the inside of
the circle. Each course will require 16 blocks to complete. You
can build the fire pit wall 7 courses high or to a lower height
if so desired. The fire pit wall will have an inside diameter of
30-1/2″ and an outside diameter of 48″. The wall cap has an
inside diameter of 32″ and an outside diameter of 50″. This fire
pit is not designed nor intended to be expanded beyond these
stated dimensions.
Those who would like to keep the Fire Pit location options open
for a possible relocation should not use adhesive. Only those
wishing to permanently install their Fire Pit should use high
strength, heat resistant concrete adhesive to glue the base
block together. Units must be dry and dust free. Apply adhesive
on the upward facing horizontal flat surface toward the outside
of the unit. This prevents the adhesive from over heating and
possibly emitting toxic fumes. It is recommended that the
adhesive be left to cure for no less than 48 hours before using
the Fire Pit.
Gluing the four (4) semi-circular charcoal colored caps to Fire
Pit base is not recommended so that the Fire Pit cavity is easier
to access for cleaning out accumulated debris. See Fire Bowl
Drainage and Construction Options for more details.
METHOD 1
CONCRETE SLAB AND PAVER CONSTRUCTION:
When building your fire pit on top of a concrete slab or paver
surface, it is recommended that a layer of geotextile or
landscaping weed barrier cloth be laid in the bottom of the pit
and turned up the inside of the block 4″.
The bottom of the fire pit cavity should then be filled with
clean sand to a depth of 4″. This will help prevent ash particles
from washing out of the bottom of the fire pit and staining the
surrounding surface.
METHOD 2
DENSE AGGREGATE BASE/FREE-STANDING INSTALLATION:
Mark out the area of the fire pit and excavate deep enough to
accommodate 6″ of well-compacted, dense-graded aggregate
stone, a 1″ layer of setting bed sand, and the 3″ thickness of
one layer of fire pit wall block that will be buried as the footer
course. Make sure the excavated soil surface is smooth and
level. Thoroughly compact the soil surface. Geotextile (Mirafi
500 or 140 N) is recommended as a separation membrane
on top of the soil surface and up the sides of the excavation
to help maintain the integrity of the dense-graded aggregate
stone base, especially when clay soils are present.
Shovel in the stone for the base and spread it evenly in layers
2″ thick. Carefully compact the stone base. For best results,
use of a vibratory plate compactor is recommended for this
purpose. Repeat this process until the stone base is 6″ deep.
Before compacting the final layer of stone, use a straight
edge and level to make sure the surface is smooth and level,
then compact and check again. If the surface is not level and
smooth, scratch the surface with a rake, smooth and level it,
and compact it again. If the fire pit is being incorporated into a
paver installation set the base course along with the pavers as
they are being installed.
For the 1″ sand setting bed, lay two or more pipes with an
outside diameter of 1″ on the stone base. Place a couple of
shovelfuls of coarse, washed concrete sand between the pipes.
Then using a straight edge, such as a 2″ x 4″, drag it across the
length of the pipes pushing and smoothing the sand. Repeat
this process until the entire surface is covered with a uniform
layer of coarse concrete sand 1″ thick. Pick up the pipes and fill
in the void left by the pipe with sand, smoothing it with a broom
or mason’s trowel.
Lay the first course (16 units total per course) of fire pit wall
block, setting the units tightly together and being careful to
lower the block straight down on to the sand. Do not drop the
units into place or set them on edge and let them flop down.
Either method will result in an uneven base course that will
cause structural unevenness in the fire pit wall. If any block are
out of alignment or the circle is distorted, tap the blocks into
place with a rubber mallet or dead blow hammer. The interior
of the circle created by the base course should be as close to
perfect as possible. The exterior dimension should vary due to
the irregular face of each block.
Once the first course has been aligned, seat the blocks into the
sand by striking them in a downward motion on the exposed
horizontal flat side of the block with a dead blow hammer or
rubber mallet. Check the top surface of the blocks to make sure
they are level from front to back, side to side, and from block
to block around the circle of block and spanning the circle of
block equatorially from one side to the other. The block should
settle into the sand about 3/8″.
Note: A surrounding soldier course makes fitting the fire pit
into a paver installation much easier to overlay and cut the field
pavers.
INSTALLING THE BLOCK
(FOR BOTH INSTALLATION METHODS)
Now set the next course of block in place. Position each course
so the blocks are centered on the joint between two blocks
beneath it. This will stagger the joints of the block providing
stronger, more stable construction as well as a more pleasing
appearance. Continue to lay block in this manner. It is optional
to apply heat tolerant adhesive toward the outside edge of the
exposed, horizontal, flat surface of each block as the block
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