Lennox Hearth CR-3835R User Manual

INSTALLATION
INSTRUCTIONS

MERIT® SERIES

36" Wood Burning Fireplaces
P/N 850,048M REV. N/C 01/2007

MODELS

CR-3835R CR-3835L

This installation manual will enable you to obtain a safe, efficient and
dependable installation of your fireplace system. Please read and under­stand these instructions before beginning your installation.

Do not alter or modify the fireplace or its components under any
circumstances. Any modification or alteration of the fireplace system,
including but not limited to the fireplace, chimney components and
accessories, may void the warranty, listings and approvals of this system
and could result in an unsafe and potentially dangerous installation.

RETAIN THESE INSTRUCTIONS

FOR FUTURE REFERENCE

IMPORTANT! TO ASSURE PROPER ALIGNMENT OF GLASS DOORS:
INSTALL THIS FIREPLACE IN A SQUARE AND PLUMB CONDITION,
USING SHIMS AS NECESSARY AT SIDES AND/OR BOTTOM.

PLEASE RETAIN THIS MANUAL FOR FUTURE REFERENCE.

OTL Report No. 116-F-20-4

NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE.

1

TABLE OF CONTENTS

Safety Rules .................................... page 2

Tools and Building Supplies ............ page 2

Precautions ..................................... page 2

Introduction..................................... page 3

Chimney/Mantel Clearances And

Height Requirements....................... page 3

Chimney System ............................. page 3

Assembly Outline............................. page 4

Location of Fireplace ....................... page 4

Assembly Steps............................... page 5

Preinstallation Notes........................ page 5

Fireplace Clearances ........................ page 5

Installing the Fireplace..................... page 5

Fireplace Specifications .................. page 6

Framing Specifications.................... page 7

Installing the Chimney System ........ page 8

30° Offset through Floor/Ceiling ...... page 9

Ten Foot Rule Summary .................. page 11

Multiple Terminations...................... page 11

Chimney Component Calculations ... page 11

Special Offset Instructions............... page 11

Offset Calculations........................... page 12

Vertical Elevation Chart................... page 13

Offset Elevation Chart ..................... page 15

Installing Offsets.............................. page 17

Combustion Air Kits ........................ page 17

Gas Line Connection........................ page 17

Glass Doors..................................... page 18

Cold Climate Insulation.................... page 18

Fireplace Finishes ............................ page 18

Mantels and Trim............................. page 18

Hearth Extensions/Wall Shields ....... page 18

Finish Requirements........................ page 20

Installation Components.................. page 21

IMPORTANT: PLEASE READ AND
UNDERSTAND THESE RULES TO
FOLLOW FOR SAFETY.

1. Before starting your fireplace installation,

read these installation instructions carefully to
be sure you understand them completely and in
entirety. Failure to follow them could cause a
fireplace malfunction resulting in serious injury
and/or property damage.

2. Always check your local building codes. The
installation must comply with all local, regional,
state and national codes and regulations.

3. These fireplaces must be installed with either
Security Chimneys model FTF8 (8" [203mm]
inside diameter) or FTF10 (10" [250mm] inside
diameter) Chimney System only. These sys­tems are intended for use in any application
where a traditional masonry type fireplace would
apply. The chimney system must always vent to
the outside of the building.

4. To ensure a safe fireplace system and to prevent
the build-up of soot and creosote, inspect and
clean the fireplace and chimney prior to use and
periodically during the heating season.

5. Use solid fuel only. DO NOT use artificial
wax based logs, chemical chimney cleaners or
flame colorants in your fireplace.

6. DO NOT use charcoal or coal under any
circumstances.

7. NEVER use gasoline, gasoline-type lantern
fuel, kerosene, charcoal lighter fluid, or similar
liquids to start or “freshen up” a fire in this
fireplace. Keep any flammable liquids a safe
distance from the fireplace.

8. NEVER leave children unattended when
there is a fire burning in the fireplace.

9. Always keep flue damper open when heat is
present in the fireplace.

10. Before servicing, allow the fireplace to
cool. Always shut off any electricity or gas to
the fireplace while working on it. This will
prevent any possible electrical shock or burns.

11. This fireplace is not intended to heat an entire
home or be used as a primary heat source. It is
designed to ensure homeowner comfort by pro­viding supplemental heat to the room.

12. Always ensure an that adequate supply of
replacement combustion air from the outside
of the house is accessible to the fire to support
normal combustion. Fireplaces consume large
volumes of air during the normal combustion
process. In the event the home is tightly sealed
with modern energy efficient features, the op­tional combustion air kit may not provide all
the air required to support combustion.

The manufacturer is not responsible for any
smoking or related problems that may result
from the lack of adequate combustion air. It is
the responsibility of the builder/contractor to
ensure that adequate combustion air has been
provided for the fireplace.

13. DO NOT use a fireplace insert or any
other products not specified herein by the
manufacturer for use with this fireplace. All
gas log sets must be operated with the
damper clamped open.

WARNING: THIS FIREPLACE HAS NOT
BEEN TESTED WITH AN UNVENTED GAS
LOG SET. TO REDUCE RISK OF FIRE OR
INJURY, DO NOT INSTALL AN UNVENTED
GAS LOG SET INTO THIS FIREPLACE.

14. "Smoke free" operation is not warranteed

nor are we responsible for inadequate system
draft caused by mechanical systems, general
construction conditions, inadequate chimney
heights, adverse wind conditions and/or un­usual environmental factors or conditions be­yond our control.

15. Never, under any circumstances, install a
fireplace, chimney component or any acces­sories, that has visible or suspected physical
damage as a result of handling or transporta­tion. These items should be inspected by your
distributor or qualified factory representative
to ensure safe condition. When in doubt, con­sult your distributor.

16. For additional safety considerations and
complete operating instructions, refer to the
Care and Operation Manual provided with the
fireplace.

TOOLS AND BUILDING SUPPLIES
NORMALLY REQUIRED

Tools should Include:

Phillips screwdriver
Hammer
Saw and/or sabersaw
Level
Measuring tape
Plumb line
Electric drill and bits
Pliers
Square

Building supplies:

Framing materials
Wall finishing materials
Caulking materials (noncombustible)
Fireplace surround and hearth
extension materials (noncombustible)

PRECAUTIONS

Note: These fireplace systems are not difficult

to install. However, in the interest of safety, it is
recommended that the installer be a qualified
or certified “tradesman” familiar with com­monly accepted fireplace installation and safety
techniques as well as prevailing local codes.

2

NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE.

The most important areas of concern dealing
with the installation of factory-built fireplaces are
clearances to combustible materials, proper as­sembly of component parts, height of the chim­ney system, the proper use of accessories sup­plied by the manufacturer and the techniques
employed in using finishing materials applied to
the wall surrounding the fireplace, hearth exten­sions and wall shields. Each of these topics will
be covered in thorough detail throughout this
manual. Please give each your special attention
as you progress with your installation.

INTRODUCTION
General Information

These fireplaces are conventional radiant heat
fireplaces with standard bar grates, optional
outside combustion air kits and optional deco­rative glass doors.

These fireplaces have been tested and listed by
Omni Test Labs (Report No.116-F-20-4) to
U.L. standard 127. These units are intended
for installation in residential homes and other
buildings of conventional construction includ­ing commercial, not in mobile homes.

TYPICAL INSTALLATION

Note: Illustrations shown reflect “typical”

installations with nominal dimensions and
are for design and framing reference only.
Actual installations may vary due to indi­vidual design preferences. However, always
maintain minimum clearances to combus­tible materials and do not violate any specific
installation requirements.

These fireplace systems are designed for in­stallation in accordance with the National Fire
Protection Standard for chimneys, fireplaces
and solid fuel burning appliances; NFPA 211
and in accordance with codes such as the
BOCA Basic/National Codes, the Standard Me­chanical Code and the Uniform Building Codes.

WARNING: FAILURE TO USE MANUFAC­TURE PROVIDED PARTS, VARIATIONS
IN TECHNIQUES AND CONSTRUCTION
MATERIALS OR PRACTICES OTHER THAN
THOSE DESCRIBED IN THIS MANUAL
MAY CREATE A FIRE HAZARD AND VOID
THE LIMITED WARRANTY.

When complete these fireplace systems con­sists of five basic “sub-systems”:

1. The Fireplace

2. The Chimney and Termination

3. The Optional Glass Doors

4. The Optional Combustion Air Kits

5. The Chimney Collar Enclosure Kit (Canada

Only) or Collar Duct Kit (U.S)

CHIMNEY CLEARANCES AND MANTEL
HEIGHT REQUIREMENTS

The fireplace may be placed on or near normal
construction materials*. The combustion air
kit, firestop spacer and roof flashings (not
chase flashings) may be placed directly on or
against normal construction materials*. The

chimney requires a minimum 2" (51 mm) air
space to combustibles (

bustible mantle may be installed 12" (305 mm)
above the opening of the fireplace as per NFPA
211, Section 7-3.3.3. In Canada the minimum
is 18" (457 mm) above the opening.

The fireplace and chimney system must be
enclosed when installed in or passing through
a living area where combustibles or people may
come in contact with it. This is important to
prevent possible personal injury or fire hazard.

See **Note

). A com-

Figure 1

Outside

Combustion

Air Kit

(Optional)

Chimney
And
Termination

CCEK
W.H.I. Approved
(Required In
Canada)

For questions, please call your distributor or
the manufacturer. Special restrictions apply to
the front and facing of the fireplace and nearby
walls (See pages 16, 17 and 18 ).

CHIMNEY SYSTEM

These fireplaces are designed and code listed
for use with Security's FTF8 and FTF10 chim­ney System only. Always use Security's FTF8
and FTF10 chimney components with these
fireplaces. Do not modify or alter these com­ponents as this may cause a potential serious
hazard and void the Warranty.

*Construction Materials:

• framing materials • paneling

• particle board • flooring

• dry wall • etc.

• plywood

** Note: 1" (25 mm) when installed with
FTF10 in the U.S. only.

NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE.

3

Insulate Joists
Same As Ceiling

Draft Stops

Firestop

CTDT
Termination

Note: Non­Combustible
Chase
Flashing
Must Be
Used To
Cover
Chase
Opening

Insulation
(Thermal Barrier)

Figure 2

8'

Level

Optional
Insulation
In Outside
Walls Of
Chase

Solid
Continuous
Surface

Outside
Base

Chimney Height

The total height of your completed fireplace sys­tem from the surface the fireplace rests on to the
chimney top must not exceed 50' (15.24 m) and
must also meet minimum height requirements.
Refer to the minimum system height chart.

Minimum System Height

FTF10 FTF8

Vertical 15'2" 16'8"
Installation (4.62 m) (5.08 m)

One 15'2" 16'8"
Offset (4.62 m) (5.08 m)

Two 25'0" 25'0"
Offsets (7.62 m) (7.62 m)

Chase Enclosure

A chase is a vertical box-like structure con­structed to surround the fireplace and chimney.
Refer to

Figure 2

for a typical chase configura­tion. As with all chimney installations, avoid
overhead obstructions such as trees, power
lines, etc. A chase should be constructed and
insulated just like any outside wall. In a cold
climate, we recommend the base of the chase
should also be insulated between the solid
continuous floor beneath the fireplace and the
chase bottom. Chase insulation in a cold cli­mate installation is not required for safety.

ASSEMBLY OUTLINE
Before You Start

LOCATION OF FIREPLACE

Carefully select the proper location for heat
circulation, aesthetics, chimney obstructions
and clearance to side wall(s). With proper pre­planning, a slight adjustment of a few inches
can save considerable time and expense later
during construction and assembly.

Inside

Corner

Installation

Hearth

Figure 4

Carefully consider the position of the fireplace
opening with respect to the location of adja­cent or nearby stairwells, bath or kitchen ex­haust fans and/or return air registers for forced
air furnaces/air conditioners that could cause
a smoking fireplace condition if the house is
tightly insulated.

When locating the fireplace, consideration must
be given to combustibles and final finishing.
See

Figure 5

and confine the final location of

combustible finish materials to the "Safe Zone".

Hearth

8" (203mm) Min.
To Protected Side
Wall

Outside
Corner
Installation

WARNING: IF INSULATION IS USED, THE
FIREPLACE MUST NOT BE PLACED DI­RECTLY AGAINST IT. INSULATION OR
VAPOR BARRIERS, IF USED, MUST FIRST
BE COVERED WITH GYPSUM BOARD,
PLYWOOD, PARTICLE BOARD OR OTHER
MATERIAL TO ASSURE INSULATION AND
VAPOR BARRIERS REMAIN IN PLACE.

WARNING: DO NOT PACK OR FILL RE­QUIRED AIR SPACES WITH INSULATION
OR OTHER MATERIAL. NO MATERIAL IS
ALLOWED IN THESE AREAS.

Note: Do not insulate the chase cavity with

blown or fill type insulation materials.
Note: Local codes may not require firestopping

at the ceiling levels for outside chase installa­tions. However, it is recommended for safety
and the reduction of heat loss.

4

Check your inventory list to be sure you have all
the necessary parts supplied in good usable
condition. Check also for any concealed damage.

Check the operation of the damper. The damper
is controlled through the use of a control lever
located within the firebox opening at the top
center just behind the firebox lintel (

Figure 3

The control lever snaps into place at the ex­treme range of motion, up and back in the
closed position. When pulled forward and
down, the damper is open.

Lintel

Damper

Closed

Damper
Open

Combustion
Air Actuator

Figure 3

NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE.

DO NOT permanently place furniture or other
items such as decorative pillows within 60" of
the fireplace front face.

Combustible
Materials

).

Allowed In
Shaded Area
“Safe Zone”

15 ⁷⁄₈”

11 ⁷⁄₈”

12"

45°

Min. Distance To

8"

Protected Side Wall
Min. Distance To

Unprotected Side Wall

Figure 5

Fireplace

8"

ASSEMBLY STEPS

Note: The following steps represent the normal

sequence of installation. Each installation is
unique, however, and might require a different
sequence.

1. Position firebox prior to framing or into
prepared framing.

2. Install the chimney system.

3. Connect house wiring to the fireplace for

later attachment of optional blower.

4. Install optional outside combustion air kit.

5. Plumb gas line if a decorative gas appliance

will be used. (Gas connections should only be
performed by an experienced, licensed/certi­fied tradesman.)

6. Complete the installation, finish wall mate­rial, surround and hearth extension to your
individual taste.

7. Assemble and attach optional glass door
assembly.

Study the three dimensional illustration (

ure 1

) to get a general idea of each element of

Fig-

your fireplace system.

PRE-INSTALLATION NOTES

The fireplace may be installed directly on a
combustible floor or raised on a platform of an
appropriate height. Do not place fireplace on
carpeting, vinyl or other soft floor coverings. It
may, however, be placed on flat wood, ply­wood, particle board or other hard surfaces.
Be sure fireplace rests on a solid continuous
floor or platform with appropriate framing for
support and so that no cold air can enter the
room from under the fireplace.

The fireplace may be positioned and then the
framing built around it, or the framing may be
constructed and the fireplace positioned into
the opening.

Usually, no special floor support is needed for
the fireplace, however, to be certain:

1. Estimate the total weight of the fireplace
system including chimney and surround ma­terials such as brick, stone, etc., to be in­stalled. Shipping weights for the fireplace may
be found on page 18.

2. Measure the square footage of the floor
space to be occupied by the system, surrounds
and hearth extensions.

3. Note the floor construction, i.e. 2 x 6’s, 2 x 8’s
or 2 x 10’s, single or double joists, type and
thickness of floor boards.

4. Use this information and consult your local
building code to determine if you need addi­tional support.

CAUTION: DO NOT BLOCK THE HEAT-CIRCU­LATING AIR INLET AND OUTLET PORTS ON
CIRCULATING MODELS. DOING SO MAY RE­SULT IN A POTENTIAL FIRE HAZARD.

If you plan to raise the fireplace and hearth
extension, build the platform assembly then
position fireplace and hearth extension on top.
Secure the platform to the floor to prevent
possible shifting.

FIREPLACE CLEARANCES

Minimum clearance to combustibles for the
appliance is as follows: sides and back - ¹⁄₂" (13
mm), floor - 0" (0 mm), adjacent wall - 12" (305
mm), ceiling - 37 ¹⁄₂" (953 mm).

INSTALLING THE FIREPLACE

Step 1. Slide the fireplace into prepared fram-

ing or position fireplace in its final position and
frame later.

The fireplace may not be recessed into a com­bustible floor. Maintain the floor to hearth clear­ance established by the fireplace lower front face.

Step 2. Insert the provided metal safety strips,
beneath the fireplace as illustrated (

and 8

). The safety strips should overlap ¹⁄₂" for

continual coverage of the floor.

Note: Safety strips are not required when fire­place rests on a noncombustible surface.

1/2" (13mm)
Clearance To
Back And Sides

Combustible
Wall

Metal
Safety Strip

1/2"

(13mm)

Fireplace And
Hearth Extension
On Raised Platform

Platform

Figures 6, 7

Hearth
Extension

Floor

1/2" (13mm)
Clearance To
Back And Sides

Combustible
Wall

Hearth

1/2"

(13mm)

Metal
Safety Strip

Extension

Fireplace And
Hearth Extension
On Floor

Floor

Figure 7
Note: Install the hearth extension only as illus-

trated.

The safety strips should extend from front of
the fireplace at least 1 ¹⁄₂" and should extend to
be at least flush with the sides. In the event a
wooden support is used to elevate the fireplace
above the floor, a “Z” type safety strip should be
fabricated and used to protect the front surface
of the wood support as well as the floor beneath
the hearth extension (

Figures 8 and 9

). The
safety strips should be tacked down to prevent
possible movement.

Note: The “Z” type safety strip is not supplied.

2"

(51mm)

Metal
Safety Strip

2"

(51mm)

Figure 8

2"

(51mm)

Special “Z”
Metal Safety Strip

Blocking

2"

(51mm)

Figure 9

Step 3. Refer to fireplace drawings and specifi-

cations on pages 6 and 7 for framing dimensions
and details. Frame appliance enclosure as illus­trated in

Figures 11 through 14

on page 8.

Figure 6

NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE.

5

IMPORTANT: UNDER NO CIRCUMSTANCES
CAN THE FIREPLACE TOP SPACERS (

6

) BE REMOVED OR MODIFIED, NOR MAY

FIGURE

YOU NOTCH THE HEADER TO FIT AROUND
OR BE INSTALLED LOWER THAN THE SPAC­ERS. THE HEADER MAY BE IN DIRECT CON­TACT WITH THE TOP SPACERS BUT MAY NOT
BE SUPPORTED BY THEM.

Note: The framed depth, 24 (610 mm) from a

framed wall, must always be measured from a
finished surface. If a wall covering such as
drywall is to be attached to the rear wall, then
the 24" (610 mm) must be measured from the
drywall surface. It is important that this di­mension be exact.

If the appliance is to be elevated above floor
level, a solid continuous platform must be
constructed.

The header may rest on the top metal spacers,
but must not be notched to fit around them.

Consult all local codes.

For Canadian Installations
Proceed with Steps 4 through 7.

Step 4. Attach the chimney collar enclosure kit,

Model CCK1, around chimney collar with the
screws provided (

Figure 10

).

FIREPLACE SPECIFICATIONS

40 1/2"

(1029mm)

37 3/8"

(949mm)

17 1/2"

(445mm)

32 7/8"

(835mm)

21"

(533m)

6"

(152mm)

17 1/2"

(445mm)

38 5/8"

(981mm)

42 3/4"

(1086mm)

Right Corner Opening

38 5/8"

(981mm)

42 3/4"

(1086mm)

Left Corner Opening

21"

(533m)

6"

(152mm)

37 3/8"

(949mm)

32 7/8"

(835mm)

40 1/2"

(1029mm)

Enclosure
Box

Figure 10

Step 5. Connect the 4" (102 mm) Class 0 air

duct provided to the collar on the chimney
collar enclosure with the screws provided in the
hardware kit.

(254mm)

(191mm)

Figure 11

10"

7 1/2

Closed End

40 1/4"

(1022mm)

10 1/2"

(267mm)

10"

(254mm)

15"

(381mm)

35"

(889mm)

42 3/4"

(1086mm)

Top View

40 1/4"

(1022mm)

24"

(610mm)

10"

(254mm)

19 7/8"

(505mm)

Open End

6

NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE.

FRAMING SPECIFICATIONS

Back Wall of Chase/Encloslure Including

Finishing Materials if any

Rough

Framing

Face

(Unfinished

Shown)

Note: No Wall Shield
Required On This Wall

D

C

Framing Without False Header

Figure 12

Back Wall of Chase/Encloslure

Rough Framing

Face (Unfinished

Shown)

Figure 13

B

Header

A

Including Finishing

Materials if any

A

Outside Corner

8" Max.

11 ⁷⁄₈"

(302mm)

C

Figure 14

Note: Combustible Materials
May Be Placed In Shaded Area.

(203mm)

45°

8" (203mm) Min. To
Protected Side Wall

Inside Corner Using Outside Air

Framing Dimensions

CR-3835 Series

A 42 ⁵₈"

(1082 mm)

C

B 40 ⁵₈"

(1032 mm)

C 24"

(610 mm)

D 34 ⁷₈"

D

Roof Framing

Figure 15

C

(886 mm)

Note: All framing dimensions calculated for 5/8"
nailing flange depth and 1/2" dry wall at the
fireplace face. If sheathing the chase or finishing
with other thickness materials, calculations will
need to be made.

B

Framing Dimensions for Ceiling

Flue Type A B
FTF8 Vertical 16 ¹⁄₂" 16 ¹⁄₂"

at 2" (419 mm) (419 mm)
FTF10 Vertical 17" 17"

at 1" (432 mm) (432 mm)
FTF10 Vertical 19" 19"

at 2" (483 mm) (483 mm)
FTF8 Offset 30° 16 ¹⁄₂" 27"

at 2" (419 mm) (686 mm)
FTF10 Offset 30° 17" 26"

at 1" (432 mm) (660 mm)
FTF10 Offset 30° 19" 28"

At 2" (438 mm) (711 mm)

Ceiling Framing

Figure 16

Framing Dimensions for Roof

Pitch FTF8 at 2" FTF10 at 1" FTF10 at 2"

CD*CD*CD*

0/12 16 ¹⁄₂" 16 ¹⁄₂" 17" 17" 19" 19"

(419 mm) (419mm) (432 mm) (432 mm) (483 mm) (483 mm)

6/12 16 ¹⁄₂" 19" 17" 19" 19" 21"

(419 mm) (483 mm) (432 mm) (483 mm) (483 mm) (533 mm)

12 /12 16 ¹⁄₂" 23 ¹⁄₂" 17" 24" 19" 26"

(419mm) (597mm) (432mm) (610 mm) (483mm) (660 mm)

*Perpendicular to roof ridge

NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE.

A

7

Step 6. Route the Class 0 air duct out the back

wall or side wall, up through the ceiling or floor
joists to an outside wall. The air duct should be
located above snow level.

Note: If the fireplace is installed against an
inside wall, the Class 0 air duct may be ex­tended into a ventilated attic space at least 18"
(457 mm) above the attic floor. Secure the duct
hood to a vertical post with the inlet positioned
downward. Ensure nothing blocks the hood
opening. This air duct must never terminate
higher than the chimney.

Step 7. Cut or frame hole through the outside
wall for the installation of the duct inlet hood.
A 4 ¹⁄₄" (114 mm) diameter hole is sufficient.
Feed the loose end of the flexible air duct
through the hole cut for the inlet hood and
attach to collar on inlet hood using two (2)
screws. Insert hood into opening. Secure in
place with nails driven through holes in hood
flange. Seal with noncombustible waterproof
silicon type caulking. If additional air duct is
needed, use Class 0 metallic air duct.

Step 8. Fireplace should be secured to side
framing members using the full length nailing
tabs at the top and bottom of the fireplace front
face. Use 8d nails or equivalent (

Figure 17

).

INSTALLING THE CHIMNEY SYSTEM

Step 1. Before continuing, check the operation

of the damper, as described on page 4, (

to Figure 3

).

Step 2. Using standard construction framing
techniques, construct opening for chimney
route up through the ceiling(s) and roof or
through an outside chase.

Framing must maintain adequate minimum air
space clearance at all times.

CAUTION: ALLOW MINIMUM 2" (51 MM)
CHIMNEY AIR SPACE TO COMBUSTIBLE
FRAMING MEMBERS THROUGHOUT VERTI­CAL OR OFFSET CHIMNEY INSTALLATION
(

SEE **NOTE

).

A minimum 2" (51 mm) air space must be
reserved for all combustible materials ex­tending for any continuous length surround­ing the chimney (

Reference

See **Note

Figures 14 and 15

).

and charts Fram­ing Dimensions for Ceiling and Roof, which
specify minimum ceiling and roof dimensions.

To determine chimney center line in new con­struction, use plumb line from roof or ceiling
above fireplace to center of flue collar on
fireplace.

refer

Note: If installing the optional collar duct kit, it
should be installed after the chimney has been
attached to the flue collar.

Step 3. Position appropriate firestop spacer at
ceiling and fasten temporarily with two (2) 8d
nails or equivalent. If chimney penetrates ceil­ing vertically, use flat firestop spacer, Model
F8FS-2 for FTF8 system and Model F10FS-2
for the FTF10 system*. If chimney penetrates
ceiling at 30° angle (offset chimney), use 30°
firestop spacer, Model F8FS30-2 for FTF8 and
Model F10FS30-2 for FTF10 system*. Use one
nail on opposite sides to hold firestop spacer
in position. Fasten permanently, using at least
two (2) more 8d nails or equivalent, after
chimney sections have been assembled
through the firestop spacer and after any nec­essary adjustments have been made. Firestop
spacer must be secured by at least four (4) 8d
nails or equivalent when completely installed.

Note: If there is a room above ceiling level,
firestop spacer must be installed on the bottom
side of the ceiling. If an attic is above ceiling
level, firestop spacer must be installed on top
side of ceiling joist (Figures 19 and 20 ).

Room Above

8d Nail Or
Equivalent

Figure 17
Note: The nailing tabs and the area directly

behind the nailing tabs are exempt from the
clearances described on page 5. Maintain at
least 1/2" clearance from the firebox wrapper to
the framing at the closest point of contact,
directly adjacent to the flange.

For remodeling, plumb to center of flue collar
from ceiling above, drive nail through ceiling
from below to mark position, then mark and
cut to passage from above ceiling (around
nail) (

Figure 18

). Then plumb from ceiling or
roof level directly above hole which has just
been completed.

Plumb Line

Figure 18

Firestop Spacer

Figure 19

Attic Above

Firestop Spacer

Figure 20
*Note: Use Models F10FS or F10FS30 when

installing FTF10 chimney in the U.S. only.
** Note: 1" (25 mm) when installed with FTF10

in the U.S. only.

8

NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE.