BRICK LEDGE
ISOKERN
BRICKLEDGE
35
Earthcore Industries
MAGNUM Series Fireplace
liner block. These four holes are provided for reinforcement
of the chimney stack by the insertion of #4, minimum, steel
reinforcing rods, and subsequent grouting
(Figures 40 &
41)
.
The brick ledge is intended for use in chimneys that rise
through the roof only where all four sides of the chimney
are bounded by the roof.
IMPORTANT:
To maintain structural performance, the DM
brick ledge must not be cut or altered in any way.
DM Brick Ledge Installation
Use of the brick ledge will require a roof framing rough
opening of at least 34” in width. The required opening
dimension along the length of the rafter, where the chimney
is to penetrate the roof line, will increase above 34” relative
to the pitch of the roof.
As the DM outer casing and inner liner assembly
approaches the roof penetration set an outer casing block
to a level of approximately 6” below the low side of the roof
framing
(Figure 41)
.
The alignment tongues on the top of this outer casing
block must be ground off to leave a flat contact surface for
the brick ledge. Temporarily leave out the inner liner that fits
this outer casing block.
Set the Isokern brick ledge onto the flat top surface
of the outer casing in a full bed of Earthcore Adhesive.
Be sure to align the four 2½” holes in the brick ledge
with the matching holes in the outer liner block below it.
Return to setting the next inner liner in the sequence. This
inner liner comes up from below and passes through the
octagonal hole in the brick ledge. The liner’s top end will be
approximately 3” above the top surface of the brick ledge.
Set the next outer liner block onto the top of the brick ledge
in a bed of Earthcore Adhesive.
Insert one piece of #4 (minimum) steel reinforcing
rod into each of the four 2½” holes in the brick ledge. The
reinforcement rods must start from a depth of at least 18”
below the bottom of the brick ledge. (In some cases, a
minimum recommendation could be 5’)
If short lengths of steel rods are used, be sure to
properly lap and wire tie all splices in the rebar. As the
reinforcing progresses, completely fill the holes with grout.
Suitable grout can be a pourable mixture of Portland cement
and sand or Portland cement, sand and pea gravel. The rebar
must be fully embedded in grout.
Leave enough of the #4 steel reinforcing rod exposed
above the brick ledge so that as the stacking of outer casing
blocks continues to termination the reinforcing rods and
grout can continue through the stack. Reinforcing shall
continue to chimney termination.
All DM chimneys that include the DM brick ledge must
be reinforced as described above.
35
DM Chimney Installation - Brick Ledge
FIGURE 40
