5
M. Install the last ring, item 23 if a Stone Age
chimney system is to be used. Install Stone Age
Adapter 235 if installing a metal pipe chimney.
Figure 6 shows the completed firebox.
Figure 6. Firebox Complete
N. If installing a mantel and side trim, especially
if it is wood or other combustible materials, make
sure the minimum distances shown in Table 2 and
Figure 2 are met.
O. Install the hearth and or hearth extension.
Make sure the Table 2 and Figure 3 clearances
and distances are maintained. Make sure that the
hearth and flooring under and in front of the
hearth are made of fully non-combustible materi-
als. - - not just a non-combustible floor covering.
When the hearth installation is complete, you are
now ready to install the exterior.
3.3 Exterior finishing
The exterior finish of an indoor fireplace will vary
as compared to an outdoor application and may be
limited depending on location in the home and
framing that encompasses the fireplace. Mantle and
exterior veneers may be fabricated stone, thin ve-
neer or full bed depth natural stone, tile, brick or
stucco.
If the exterior finish is going to be stucco, stain, tile
or manufactured thin stone wrap outside of firebox
with metal lathe. Attach metal lathe to firebox us-
ing concrete nails, tapcons, masonry or concrete
anchors. Natural stone, full bed depth or thin ve-
neer, full size brick, concrete pavers, CMU block,
etc. do not require metal lathe.
Make sure same refractory mortar is used.
4.0 Installation of Chimney
Either one of two types of chimney can be in-
stalled. One is a Stone Age masonry chimney sys-
tem and the other is metal pipe. If metal chimney
pipe is used make sure pipe is tested and certified
to UL 103 standards for the US and ULC S604
standards for Canada.
4.1 Stone Age Masonry System
The Stone Age Masonry chimney system consists
of stacking Stone Age chimney blocks (item 23)
and installing a clay flue inside.
A. Place a clay flue inside the chimney block
(23). The holes in each corner of the chimney
block (23) are for mortar and rebar.
B. Continue with stacking these (23 and clay
flue) items until the desired height is reached.
Mortar the flue sections together, and mortar the
chimney block sections together. There will be
dead air space between the flue and chimney
block sections.
C. The chimney is completed by stacking as
many flue sections as necessary to reach chimney
height. Chimney plumbing can either be straight
through the ceiling and through the roof, or if the
fireplace is installed on an outside wall, the chim-
ney can be external to the house. When needed
offset blocks can be used for the chimney and
should be engineered to structurally support the
offset with CMU or custom fabricated steel post
and or angle iron capable of supporting the weight
and height of the chimney. Never exceed more
than a 30 degree angle when offsetting a chimney.
D. When using metal pipe, as the chimney ex-
tends through the attic to the roof, attach securing
straps to rafters and joists as required to provide
stability.
E. If chimney exit opening does not already exist
locate the point where the chimney will exit the
roof by plumbing down to the center of the fire-
place chimney. Drive a nail into the roof to mark
the center.
