Osburn Stratford User manual

STOVE BUILDER INTERNATIONAL INC.
1700 Leon-Harmel Street, Quebec City, Quebec, Canada, G1N 4R9 Tel.: [phone]
45178 Printed in Canada
MODEL OSBURN STRATFORD
Installation Instructions
This installation manual will help you obtain a safe, efficient, dependable installation for
your fireplace and chimney system. Please read and understand these installation
instructions before beginning your installation.
CAUTION:Do not attempt to modify or alter the construction of the fireplace or its
components. Any modification or alteration of construction may void the warranty,
listings and approvals of this system. In that case, Stove Builder International (SBI) will
not be responsible for damages. Install the fireplace only as described in these
instructions.
PLEASE RETAIN THIS MANUAL
FOR FUTURE REFERENCE
Listed to standards ULC-S610 and UL-127
Manufactured by:
Stove Builder International Inc.

TABLE OF CONTENTS
Page
1. SAFETY RULES FOR OPERATING YOUR FIREPLACE.......................................................... 3
2. CERTIFICATION LABEL................................................................................................................ 5
3. THE FIREPLACE .............................................................................................................................. 6
3.1 INTRODUCTION.............................................................................................................................. 6
3.1.1 Parts Required ............................................................................................................................... 6
3.1.2 Additional Equipment (optional)................................................................................................... 6
3.2 OPERATING THE OSBURN STRATFORD.................................................................................. 7
3.2.1 Fuel................................................................................................................................................ 7
3.2.2 The use of manufactured logs........................................................................................................ 7
3.2.3 First Fires....................................................................................................................................... 8
3.2.4 Building a Fire............................................................................................................................... 8
3.2.5 Maintaining the Fire...................................................................................................................... 8
3.2.6 Primary Air.................................................................................................................................... 9
3.2.7 Combustion Settings.................................................................................................................... 10
3.2.8 Smoking
− Causes and Troubleshooting..................................................................................... 11
3.3 MAINTAINING YOUR OSBURN STRATFORD ........................................................................ 13
3.3.1 Creosote – Formation and Need for Removal............................................................................. 13
3.2.2 Chimney Maintenance................................................................................................................. 13
3.3.3 Top Baffle Removal Prior to Cleaning the Chimney.................................................................. 13
3.3.4 Dealing with a Chimney Fire ..................................................................................................... 14
3.3.5 Plated Finish Maintenance .......................................................................................................... 14
3.3.6 Disposal of Ashes........................................................................................................................ 15
3.3.7 Refractory Replacement.............................................................................................................. 15
3.3.8 Glass Care – Replacement........................................................................................................... 15
3.3.9 Glass Care – Cleaning................................................................................................................. 16
3.3.10 Gasket Replacement.................................................................................................................... 16
3.4 FIREPLACE INSTALLATION ..................................................................................................... 17
3.4.1 Locating the OSBURN STRATFORD........................................................................................ 17
3.4.2 Heart Extension Requirements.................................................................................................... 18
3.4.3 Framing, Facing, Mantel, and Combustible Shelf....................................................................... 18
3.4.4 Blower connection....................................................................................................................... 22
3.5 HOT AIR DUCTING INSTALLATION ....................................................................................... 23
3.5.1 Gravity Kit................................................................................................................................... 23
3.5.2 Central Forced Air Kit (Not tested under EPA certification)...................................................... 25
3.6 FRESH AIR KIT (Optional) ........................................................................................................... 27
3.6.1 Outside Air Installation ............................................................................................................... 27
3.7 DOOR OVERLAY INSTALLATION ........................................................................................... 28
4. THE CHIMNEY................................................................................................................................ 29

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4.1 CHIMNEY INSTALLATION NOTES .......................................................................................... 29
4.2 CHIMNEY INSTALLATION INSTRUCTIONS ......................................................................... 30
4.3 OFFSET CHIMNEY INSTALLATION ........................................................................................ 33
4.4 ANGLED WALL RADIATION SHIELD ..................................................................................... 37
4.5 CHIMNEY SUPPORT INSTALLATION ..................................................................................... 38
4.6 CHIMNEY CHASE AND MULTIPLE TERMINATIONS......................................................... 38
4.7 INSTALLATION INSTRUCTIONS FOR MASONRY APPLICATION .................................. 40
5. OPTIONS ........................................................................................................................................... 41
6. APPENDIX ........................................................................................................................................ 42
7. OSBURN LIMITED LIFETIME WARRANTY............................................................................ 46

3
1. SAFETY RULES FOR OPERATING YOUR FIREPLACE
•Use only an Osburn glass door, specifically designed for the model Osburn Stratford.
•When cleaning the fireplace, the ashes should be placed in a metal container with a tight
fitting lid. The closed container of ashes should be placed on a non-combustible floor or on
the ground outside the house, pending final disposal. If the ashes are disposed of by burial in
soil or otherwise locally dispersed, they should be retained in the closed container until all
cinders have thoroughly cooled.
CAUTION:NEVER USE GASOLINE, KEROSENE, CHARCOAL LIGHTER FLUID
OR SIMILAR LIQUIDS TO START OR REKINDLE A FIRE IN THIS
FIREPLACE. KEEP ALL SUCH LIQUIDS WELL AWAY FROM THE
FIREPLACE AT ALL TIMES.
CAUTION: KEEP COMBUSTIBLE MATERIALS AT LEAST 48 INCHES AWAY
FROM THE FRONT OF THE FIREPLACE OPENING.
CAUTION: NEVER LEAVE CHILDREN UNATTENDED WHEN THERE IS A FIRE
BURNING IN THE FIREPLACE.
CAUTION: NEVER USE GRATE OR ELEVATE FIRE. BUILD WOOD FIRE
DIRECTLY ON HEARTH.
CAUTION: DO NOT USE A FIREPLACE INSERT AND OTHER PRODUCTS NOT
SPECIFIED FOR USE WITH THIS FIREPLACE.
WARNING: THIS FIREPLACE HAS NOT BEEN TESTED WITH AN UNVENTED OR
VENTED GAS LOG SET. TO REDUCE RISK OF FIRE OR INJURY, DO
NOT INSTALL AN UNVENTED GAS LOG SET INTO THIS FIREPLACE.
WARNING: DO NOT USE MATERIALS OTHER THAN THOSE LISTED IN THE
REPLACEMENT PARTS SECTION DURING INSTALLATION AS THEY
MAY BE SAFETY HAZARDS, AND A FIRE COULD RESULT.

4
PLEASE NOTE THAT THE PICTURES SHOWN IN THIS
MANUAL ARE GENERIC AND MAY NOT MATCH
EXACTLY THE LOOK OF YOUR FIREPLACE.
REGISTER YOU WARRANTY ONLINE
To receive full warranty coverage, you will need to show evidence of the date you
purchased your unit. Keep your sales invoice. We also recommend that you
register your warranty online at
www.osburn-mgf.com
Registering your warranty online will help us track rapidly the information we need
on your unit.

5
2. CERTIFICATION LABEL

6
3. THE FIREPLACE
3.1 INTRODUCTION
The OSBURN STRATFORD fireplace is an energy efficient, heat circulating, close combustion
fireplace. You will receive a lifetime of comfort and enjoyment from your fireplace provided it is
installed, maintained and operated properly.
•Please read these instructions and retain this manual for future reference.
•Before beginning the fireplace installation, consult the local authorities to obtain your
building permit and check your local building codes. Install the fireplace only as described in
these instructions and using only components from the manufacturers listed in table 2.
•The OSBURN STRATFORD is not intended for use with a gas log. Failure to follow these
instructions will void the certification and the warranty of the fireplace and may result in an
unsafe installation.
3.1.1 Parts Required
•Fireplace model OSBURN STRATFORD
•Insulated chimney made by the manufacturers listed in table 2, with the corresponding
specifications :
−Chimney lengths
−Elbows (where necessary)
−Associated components as per these installation instructions.
3.1.2 Additional Equipment (optional)
•Forced air kit
•Gravity venting system
•Outside air kit
•Fireguard

7
3.2 OPERATING THE OSBURN STRATFORD
3.2.1 Fuel
The OSBURN STRATFORD is designed to work best when fuelled with seasoned cordwood. Use
solid wood or processed solid fuel firelogs only. Hardwoods are preferred to softwoods since the
energy content of wood is relative to its density. Hardwoods will result in a longer burning fire
and less frequent refuelling. A moisture content of 15% to 20% (seasoned) is recommended.
Wood that has been cut and split and let to dry under a cover for a period of one year will usually
meet that criteria. Excessively wet wood will be difficult to burn and will result in lower
efficiency, increased creosoting and deposits on the glass and in the chimney. Excessively dry
wood will burn well but will also have higher emissions and shorter burning time.
Do not burn scrap or garbage, treated wood or wood such as driftwood from the ocean which has
been exposed to salt or other chemicals. Salt or chemicals can corrode the firebox and chimney.
Do not burn large amounts of paper, cardboard, Christmas tree branches or building construction
materials. Intense firing with these materials may overheat the fireplace, causing damage to the
unit, a fire or even possibly igniting a chimney fire if the chimney is creosoted.
CAUTION:DO NOT OVER FIRE THIS HEATER OVER FIRING CAN RESULT IN A SAFETY HAZARD AND CAN
PERMANENTLY DAMAGE THE FIREPLACE AND CHIMNEY.
3.2.2 The use of manufactured logs
There are numerous types of manufactured logs sold on the market. You must be very careful
with this type of product. Many brands of manufactured logs contain chemical additives. DO
NOT BURN ANY MANUFACTURED LOGS CONTAINING CHEMICAL ADDITIVES. IF
YOU DO, YOU MAY OVERHEAT YOUR FIREPLACE, THEREFORE CAUSING A FIRE
HAZARD AND VOIDING YOUR WARRANTY. Logs containing chemical additives burn a lot
hotter and were designed for decorative fireplaces. Decorative fireplaces generally have larger,
cooler, and less air-tight fireboxes. Your OSBURN STRATFORD, on the other hand, has a
smaller, completely sealed firebox which attains much higher temperatures. It is therefore not
designed to support excessive heat caused by the addition of chemicals in manufactured logs.
Manufactured logs made of 100% wood residues do not pose a threat to your fireplace.
However, they must be used carefully. Manufactured logs typically release a much larger heat
output over a short period of time. Therefore, you cannot place a large quantity of such logs into
your fireplace. Start with one log, and gradually increase the load. Never put more than 4 logs.
The logs should be of an average size and not exceed 8 inches in diameter.
WARNING: Do not poke or stir the logs while they are burning. Use only firelogs that have
been evaluated for the application in fireplace and refer to firelog warnings and caution markings
on packaging prior to use.

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3.2.3 First Fires
The fresh paint on your fireplace needs to be cured to preserve its quality. Once the fuel load is
properly ignited, only burn small fires in your fireplace for the first four hours of operation.
Never open the air control more than necessary to achieve a medium burn rate. Make sure that
there is enough air circulation while curing the stove. Open one or more windows. The odours
can be smelled during the 3 or 4 first fires.
3.2.4 Building a Fire
To start a fire, place several crumpled up balls of newspaper in the firebox behind the andiron.
Place small dry pieces of kindling on top of the paper, criss-crossing the kindling so that there are
air spaces in between. Keep the fuel far back enough so that air can get underneath. Open the air
controls fully and light the newspaper. Once the newspaper and the kindling is well ignited, close
the door. Once the kindling fire is well established, cordwood can be added. (See Primary Air
Combustion Control section for proper operation of the air controls.). Make sure that cordwood is
always behind the andiron.
The unit will burn best with 2-3 pieces of cordwood spaced 1 to 2 inches apart and allowing air to
get under the fuel. Criss-crossing or arranging the fuel so that air can get underneath, will help the
fire to get started easily. The unit should be operated with the air control fully open long enough
to get the cordwood well ignited
3.2.5 Maintaining the Fire
Once the wood has been consumed (or partially consumed) and you have obtained a good bed of
embers, you should reload the unit. In order to do so, open the air control to its maximum for
approximately 15 seconds prior to opening the fireplace door. Then, proceed by opening the door
very slowly. Open it by 2" to 4" (52 to 104 mm) for 10 seconds before opening it completely.
This procedure will increase the draft and thus eliminate the smoke which is stagnant in a state of
slow combustion in the fireplace. Then, bring the red embers to the front of the stove and reload
the unit.
Your OSBURN STRATFORD fireplace will work best if a thick bed of hot embers is maintained
in the bottom of the firebox, and a minimum of two large pieces of seasoned fuel are added.
Combustion efficiency is largely related to establishing a hot ember bed, and hot firebox
temperatures. The quicker the fireplace and chimney (flue) get up to normal operating
temperatures, the better. A small intense fire is preferred to a large smouldering fire, both to
improve combustion efficiency and to reduce the amount of creosote build-up. The best
performance will be obtained by adding relatively small amounts of fuel to a well established
ember bed, and then operating with the air inlet control open long enough to achieve a hot fire.
Use a poker to make an air channel in the embers below the wood. This will allow air to flow
under the wood for a more efficient burn. Once you have reached the desired temperature, the
primary air can be set to a medium setting. You know you have reached the desired temperature
when, closing the primary air control, you can see a flame at the top of the firebox. The benefit of
this technique will be cleaner glass, less creosoting, greater efficiency and the most pleasing fire
for your enjoyment.

9
In order to achieve an optimum efficiency from your unit, we suggest that you operate it with the
air control completely closed. Make sure that you have a good fire going and an adequate ember
bed before you completely close the air control. Closing the air control too soon will lower
combustion efficiency and may cause the fire to die out. The addition of a blower (if not already
included) is highly recommended to maximize your unit’s efficiency.
3.2.6 Primary Air
There is no flue damper in the OSBURN STRATFORD. As in common with air tight stoves, the
combustion air control sets the flow of air entering the firebox. This allows for a more precise
control of the fire. The combustion air control is located below the door on the right side. The
main source of air (primary air) entering the firebox can be diminished by moving the air
combustion control from right to left. The primary air is fully opened when the air control is
completely moved to the right. The combustion air control should be in the closed position
(primary air) when the fireplace is not in use. This will minimize air leakage up the chimney. The
combustion air control should be opened before opening the door to minimize the possibility of
back draft coming into the room.
SLOW
MEDIUM
ACCELERATED
Figure 1

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3.2.7 Combustion Settings
Accelerated Combustion
The maximum heat output for the OSBURN STRATFORD is achieved by burning with the door
closed and the combustion air opened. By this method, the OSBURN STRATFORD can produce
up to 75,000 BTU of heat per hour. However, it will be necessary to reload with wood every one
or two hours. This is the least efficient method of burning the OSBURN STRATFORD. Use
caution when firing with the combustion air control wide open. Only burn cordwood in this
manner. Small dry pieces of softwood and construction scraps will burn very intensely using this
method and may damage the firebox.
Medium Combustion
This is the recommended mode of operating the OSBURN STRATFORD and should be the one
normally used since it will deposit the least amount of creosote on the glass and in the chimney.
The combustion air control must be ¾ closed. The precise setting will depend on many factors,
including chimney length and the moisture content of the wood.
For instance, a long chimney will necessitate closing the combustion air control. To obtain the
proper combustion, close the combustion air control completely, then open it about ¼" to ½".
Three medium size pieces of wood should be burning on a bed of hot coals. The heat output will
be approximately 35,000 BTU per hour and the loading time will be about every 3-4 hours.
Softwoods may be burned using this method but the time will be substantially reduced.
Slow Combustion
When the air combustion control is completely closed, the fireplace is in a slow combustion
phase. If the heart is hot enough, slow combustion will not stop the fire, but there will be a
noticeable change in the flame pattern. The flames will be slow and may appear dirty if the wood
is too wet (moisture content of 20% and more). Do not allow the wood to burn without flame,
since this will produce excessive creosote in the unit.
Creosote may accumulate on the glass door. This method of burning should be used only after
operating the OSBURN STRATFORD with the air control opened to produce a hot fire for about
an hour or at medium pace for at least 2 hours. Slow combustion can be used at night in order to
reduce the heat output and to prolong the burn. The refuelling interval time will be between 6-8
hours.

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3.2.8 Smoking − Causes and Troubleshooting
To reduce the likelihood of smoking when opening the door, set the combustion air controls to
the right (accelerated) before opening the door. Your fireplace has been designed and tested to
provide smoke free operation. Occasionally, there may be a small amount of smoking upon
lighting the fire, until the chimney heats up but this should not continue. If the fireplace continues
to smoke it is probably for one of the following reasons:
A. Negative pressure in the house
As the fire burns, air goes up the chimney. This air must be replaced through leakage into the
house or through the fresh air kit. When operating the OSBURN STRATFORD, open a nearby
window temporarily to check if there is adequate air supply replacement. If opening a
window solves the problem, the house is under negative pressure.
B. Fans operating (e.g. : range hood)
These fans draw air out of the house and may actually cause a negative pressure in the house.
Turn off all fans and open a nearby window to determine if this is the cause of the problem.
C. Wet wood
Wet or tarred wood will smoulder and smoke instead of burning properly.
D. Dirty or blocked chimney
Check to make sure the chimney is clear and clean.
E. Chimney not long enough
The minimum system height is 15 feet (4.6m). The chimney must extend at least 3 feet (915
mm) above its point of contact with the roof and at least 2 feet (0.6 m) higher than any roof or
wall within 10 feet (3 m) of it. When installed with offsets, the minimum system height is 15
feet (4.6 m) to 17 feet (5.2 m) as per Table 1. Additional height will increase draught and will
decrease the tendency to smoke. If only the minimum chimney height is installed, operating
conditions must be optimal (interior chimney, minimum height of 18” before any offset, etc.).
F. Poor chimney draft
With no fire, there should be sufficient draught to exhaust cigarette smoke introduced under
the baffle. Chimneys installed against an outside wall without protection may generate back
draught problems which will cause start-up problems. To prevent this, open a nearby window,
roll up a piece of paper and light it. Then, hold it in the upper part of the firebox to warm up
the chimney. Wait until the draught is sufficient, then start the fire.

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IMPORTANT NOTES
A. Do not block the hot air vents to the fireplace as this will cause the fireplace to overheat.
B. Never start a fire using gasoline, kerosene, charcoal lighter fluid or any other combustible
liquid.
C. Do not burn coal. The sulphur in coal will corrode the firebox.
D. Do not burn driftwood which has been in the ocean or salt water. The salt will corrode the
firebox and chimney.
E. Do not abuse the unit by burning paper, or cardboard or construction material such as pressed
wood, plywood or lumber.
F. Do not allow the wood to smoulder or burn without flame, since this will produce excessive
creosote in the unit.

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3.3 MAINTAINING YOUR OSBURN STRATFORD
3.3.1 Creosote – Formation and Need for Removal
When wood is burned slowly without a flame, it produces tar and other organic vapours which
combine with expelled moisture to form creosote. The creosote vapors condense in ; the
relatively cool chimney flue of a slow-burning fire. As a result, creosote residue accumulates on
the flue lining. When ignited this creosote makes an extremely hot fire.
The chimney shall be inspected at least twice a year during the heating season to determine when
a creosote build-up has occurred.
When creosote has accumulated it shall be removed to reduce the risk of a chimney fire.
3.2.2 Chimney Maintenance
Regular chimney inspection and maintenance combined with proper operation will prevent
chimney fires. Keep your chimney clean. Do not allow more than 1/16″creosote build up in your
chimney. The amount of creosote will depend on variables such as frequency of use and type of
fire. We recommend that you:
A. Initially inspect the chimney system weekly. From this, you will learn how often it will be
necessary to clean your chimney.
B. Have your chimney cleaned by a qualified chimney sweep. If you wish to clean it
yourself, we recommend using a stiff plastic or non-metallic brush. If a metal brush is
used, its size should be slightly smaller than the flue to avoid damaging the chimney. Do
not use a brush that will scratch the stainless steel interior of the chimney.
C. Do not expect chemical cleaners to keep your chimney clean. The rain cap can be
removed for inspection and/or cleaning of the chimney.
3.3.3 Top Baffle Removal Prior to Cleaning the Chimney
Before starting to clean your chimney, we recommend that you remove the top baffle to avoid
creosote dust collection at the top of the baffle. Follow these steps to set the top baffle out of the
way:
1. Remove the front air tube by pulling out the cutter pin on the side of the tube. They are
located at the top, underneath the baffle.
2. Lift the baffle and slide it out of the fireplace. You now have access to the chimney.

14
Figure 2
3.3.4 Dealing with a Chimney Fire
Regular chimney maintenance and inspection can prevent chimney fires. If you have a chimney
fire, follow these steps:
1. Close the fireplace door and the combustion air controls;
2. Alert your family of the possible danger;
3. If you require assistance, alert your fire department;
4. If possible, use a dry chemical fire extinguisher, baking soda or sand to control the fire. Do
not use water as it may cause a dangerous steam explosion;
5. Check outside to ensure that sparks and hot embers coming out of the chimney are not
igniting the roof;
6. Do not use the fireplace again until your chimney and fireplace have been inspected by a
qualified chimney sweep or a Fire Department Inspector;
3.3.5 Plated Finish Maintenance
Use a glass cleaner and a soft cloth to polish the plated finish on the door frame. Do not use
abrasives such as steel wool, steel pads or an abrasive polish for they may scratch the finish.
FRONT AIR
TUBE

15
3.3.6 Disposal of Ashes
Do not attempt to clean the fireplace when the unit is hot. Ashes should be placed in a metal
container with a tight fitting lid. The closed container of ashes should be placed on a non-
combustible floor or on the ground, well away from combustible materials pending final disposal.
If the ashes are disposed of by burial in soil or otherwise locally dispersed they should be retained
in the closed container until all cinders have thoroughly cooled. Do not attempt to clean the stove
when the unit is hot.
3.3.7 Refractory Replacement
The intense heat of the fire will normally cause hairline cracks in the refractory. These cracks can
be minimized by proper curing as described in “First Fires”. They will not normally diminish the
effectiveness of the refractory. If large cracks develop, then the refractory should be replaced. To
replace the refractory bricks, follow these steps:
1. Remove the andiron
2. Remove the bottom stone
3. Remove the side stone retainers
4. Remove the left stone
5. Remove the right stone
6. Remove the back stone
To install the new bricks, follow the
above steps in reverse. 1
2
3
4
5
6
Figure 3
3.3.8 Glass Care – Replacement
The glass used for the OSBRUN STRATFORD is a high temperature ceramic glass (1400º F). Do
not abuse the glass door by striking or slamming shut. If the glass breaks, it must be replaced
with an identical ceramic glass. Tempered glass or ordinary glass will now withstand the high
temperatures of the OSBURN STRATFORD. Replacement glass should be purchased from a
Osburn dealer (see “Replacement Parts”, in Section 7 – APPENDIX). Do not operate the unit
with a cracked or broken glass.

16
3.3.9 Glass Care – Cleaning
The OSBURN STRATFORD is designed to keep the glass clean under normal operating
conditions. If the OSBURN STRATFORD is operated continuously with the combustion air
controls closed, the glass will tend to get dirty unless the fuel, firebox and glass are maintained at
hot. To clean the glass, there are a number of specially designed cleaners. Your authorized
Osburn dealer can recommend a suitable cleaner which is available in your area. Regular
household glass cleaners will not clean creosote. Do not use abrasives such as steel pads, steel
wool or oven cleaner as they will scratch the glass. Only wash when the stove is cold.
3.3.10 Gasket Replacement
Remove the doors from the unit and lay them on a clean, unabrasive surface. To replace the
gasket around the door frame, first remove the old gasket and adhesive. Make sure that the
surface is totally clean before applying new adhesive (a high temperature silicone caulking rated
for at least 500ºF, 260ºC, is suitable) or adhesion problems may result. Apply the adhesive inside
the door groove (gasket channel) and install the new gasket with a gentle pressure. Let dry for at
least 24 hours. To replace the glass gasket, simply remove the glass retainers holding the glass to
the door frame. Remove the glass and peel off the gasket surrounding it. Replace it by a new,
self-adhesive glass gasket. The proper replacement gaskets are available from your Osburn
dealer in the following dimensions:
Gasket Length Dimensions
Around each glass 51 ½" (131 cm) U SHAPE
On each door frame 41 ¼" (105 cm) Flat ¼" x ½"
Along the door joint 14" (36 cm) Flat ¼" x ½"

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3.4 FIREPLACE INSTALLATION
3.4.1 Locating the OSBURN STRATFORD
A. The best location to install your fireplace is determined by considering the location of
windows, doors, and the traffic flow in the room where the fireplace is located, allowing
space in front of the unit for the heart extension and the mantel, and taking into consideration
the location of the hot air ducts (optional), outside air kit and chimney. If possible, you should
choose a location where the chimney will pass through the house without cutting floor or roof
rafters.
B. Usually, no additional floor support is needed for the fireplace. The adequacy of the floor can
be checked by first estimating the weight of the fireplace system. Weights are given in the
appendix. Next, measure the area occupied by the fireplace which is normally 36¾" × 26".
Note the floor construction and consult your local building code to determine if additional
support is needed.
C. The OSBURN STRATFORD may be installed directly on the floor or on a raised base (for
proper guidelines, refer to “Heart Extension Requirements”) and a minimum of 7 feet (2.15
m) measured from the base of the appliance to the ceiling is required. The hearth extension is
to be installed only as illustrated in the drawing below.

18
3.4.2 Heart Extension Requirements
The OSBURN STRATFORD may be installed directly on a combustible floor; however, the
combustible floor in front of the fireplace must be covered with a non-combustible material (tile,
marble, stone, etc.). The hearth extension floor area shall extend at least 16" in front and at least
8" on each side of the fireplace opening. (see figure 4). The floor protector in front of the fireplace
must have a R value of 1.53 or greater.
Convert specification to R-value:
k-factor is given with a required thickness (T) in inches: R=1/k x T
C-factor is given: R=1/C
41 3/4"
16"
3"
45°
50" MIN.
6.000" 17" MIN.
COMBUSTIBLE
SHELF
AREA WHERE
WOOD MANTEL
CAN BE INSTALLED
NON COMBUSTIBLE
MATERIAL
Figure 4
3.4.3 Framing, Facing, Mantel, and Combustible Shelf
The construction of the framing, facing, and mantel must be in accordance with the standards and
the following illustrations (figures 4 to 11):
A. Frame the fireplace using 2" × 3" or heavier lumber.
B. WARNING:Combustible framing material cannot be used in the space directly above the
fireplace, except for the studs above the facing that support the facing material and mantel.
This area must remain empty for a height of 7′(2,15 m) measured from the base of the
appliance.
C. Frame the fireplace with vertical studs at the sides of the fireplace running from floor to
ceiling (see figure 6). Position the studs back from the front edge of the fireplace, a space the

19
thickness of the facing material so that the facing can be installed flush with the fireplace
facing (within limitations of figure 11). Frame headers between the vertical studs only as
follows:
−Place 2" × 3" or 2" × 4" headers, only along the upper part of the front, side and back
faces. Do not put wood or any combustible material within the area above the fireplace
except on the front facing.
−Place headers only as required to support the facing and mantel.
D. WARNING: DO NOT PACK REQUIRED AIR SPACES WITH INSULATION OR
OTHER MATERIALS.
THE FIREPLACE MUST NOT BE IN CONTACT WITH ANY INSULATION OR
LOOSE FILLING MATERIAL. COVER THE INSULATION WITH GYPROC
PANELS AROUND THE FIREPLACE.
Figure 5 Figure 7
Figure 6 Figure 8
37 31/32"
19 13/16"
53 23/32"
75 31/32"
20" 1 1/2"
22 7/8"
36"
36 3/4"
8 3/32"
26"
24 1/32"
12 13/32"
10 1/4"
2"
7' MIN.
43 3/16"
36"
24 1/32"
38"
431
4"
363
4"