Section 27-848.08. Wood burning appliances: Installation

(a) Scope. Wood
  burning appliances include factory-built fireplaces,  fireplace  stoves,
  room heaters, and fireplace inserts.
    (b)  Listing. Wood burning appliances shall be listed and accepted and
  shall be installed in accordance with the terms  of  their  listing  and
  acceptance.
    (c) Location of appliances.
    (1)  Every  appliance  shall  be  located  with  respect  to  building
  construction  and  other  equipment  so  as  to  permit  access  to  the
  appliance.  Sufficient  clearance shall be maintained to permit cleaning
  of surfaces, the replacement of air filters, blowers,  motors,  controls
  and  chimney  connectors,  and  the  lubrication and servicing of moving
  parts.
    (2) Wood burning appliances shall not be installed in confined  spaces
  or alcoves. The minimum size of the space or room in which the appliance
  is  located  shall  be three hundred cubic feet. There shall be at least
  one openable window serving such space or room.
    (3) Wood burning appliances shall not be  installed  in  any  location
  where  gasoline  or  any  other  flammable  liquids, vapors or gases are
  present or likely to be present.
    (4) Wood burning appliances shall not be installed in any garage.
    (d) Air for combustion and ventilation. Wood burning appliances  shall
  be  installed  in  a  location  in  which the facilities for ventilation
  permit proper chimney draft and maintenance of  safe  temperature  under
  conditions  of use and provide sufficient air to prevent carbon monoxide
  from entering the dwelling space. Appliances shall be located so as  not
  to  interfere  with  proper  circulation of air within the heated space.
  Where buildings are so tightly sealed that normal infiltration does  not
  provide the necessary air, outside air shall be introduced.
    (e) Mounting for residential type appliances.
    (1)  Residential  type  wood  burning  appliances  that are tested and
  listed by an accepted national testing laboratory  for  installation  on
  floors  constructed  of  combustible  materials  shall be placed on such
  floors in accordance with  the  requirements  of  the  listing  and  the
  conditions  of  acceptance.  Such  appliances  which  are not listed for
  installation on combustible  floors  by  an  accepted  national  testing
  laboratory  shall  be  provided with floor protection in accordance with
  the provisions of subdivision (g) of this section. Residential type wood
  burning appliances are permitted to be placed without  floor  protection
  in any of the following manners:
    a.  on  concrete bases adequately supported on compacted soil, crushed
  rock or gravel;
    b. on concrete slabs or masonry arches that do  not  have  combustible
  materials attached to the underside; or
    c.  on  accepted  assemblies  constructed  entirely of non-combustible
  materials, and having a fire resistance rating  of  not  less  than  two
  hours, with floors constructed of noncombustible materials.
    (2)  Any  floor  assembly,  slab  or  arch  shall extend not less than
  eighteen inches beyond the appliance on all sides.
    (3) In lieu of the requirements for floor protection specified herein,
  a  floor  protector  listed  by  a  recognized  testing  laboratory  and
  installed in accordance with the installation instructions may be used.
    (4)  Appliances  shall be supported by concrete bases, concrete slabs,
  masonry arches and floor ceiling assemblies and their supports which are
  designed and constructed to support the appliance.
    (f) Mounting for fireplace stoves and room heaters.
    (1) Fireplace stoves and  room  heaters  which  are  set  on  legs  or
  pedestals that provide not less than six inches of ventilated open space

  beneath  the  fire  chamber  or  base  of the appliance may be placed on
  floors  of  combustible  construction,  provided  the  floor  under  the
  appliance  is protected with closely spaced solid masonry units not less
  than  two  inches  in thickness. The top surface of the masonry shall be
  covered with sheet metal not less than  24  gauge  (0.024  inches).  The
  floor  protection  shall extend not less than eighteen inches beyond the
  appliance on all sides.
    (2) Fireplace stoves  and  room  heater  which  are  set  on  legs  or
  pedestals  providing  two to six inches of ventilated open space beneath
  the fire chamber or base of the appliance may be  placed  on  floors  of
  combustible  construction,  provided  the  floor  under the appliance is
  protected with one course of hollow masonry units  not  less  than  four
  inches  in thickness. The masonry units shall be laid with ends unsealed
  and joints matched in such a way as to provide a free circulation of air
  through the core spaces of the masonry. The top surface of  the  masonry
  shall be covered with sheet metal not less than 24 gauge (0.024 inches).
  The  floor  protection shall extend not less than eighteen inches beyond
  the appliance on all sides.
    (3) Fireplace stoves and room heaters  with  legs  or  pedestals  that
  provide  less  than two inches of ventilated open space beneath the fire
  chamber or base of the appliance  shall  not  be  placed  on  floors  of
  combustible construction.
    (g)  Clearances.  Woodburning  appliances  shall be installed with the
  following minimum clearances to combustible construction: Above the  top
  of  appliance--thirty-six  inches;  from  front--thirty-six inches; from
  back--thirty-six inches;  from  sides--thirty-six  inches.  The  minimum
  clearance  to noncombustible construction shall be six inches when table
  14-1 herein is used except that forty-eight inches shall  be  maintained
  where  the  fuel  is  inserted. Accepted stoves shall be exempt from the
  above-mentioned clearances and shall be installed in accordance with the
  appropriate  reference  standard  and  clearances  determined  therefrom
  through tests specified in the reference standard.
    (h) Reduction of clearances from wood burning appliances.
    (1)  Clearances  from  listed  and unlisted wood burning appliances to
  combustible material may be  reduced  if  the  combustible  material  is
  protected as described in table 14-1 herein and as shown in figures 14-6
  to 14-10 herein.
    (2)  Clearances  from  wood burning appliances to combustible material
  may be reduced by the use  of  materials  or  products  listed  for  the
  purpose  of  reducing such clearances. Materials and products listed for
  such purpose shall be installed in accordance with the conditions of the
  listing and the manufacturer's instructions.
    (3) For clearance reduction systems  using  an  air  space  between  a
  combustible  wall  and wall protector, adequate air circulation shall be
  provided by one of the  following  methods  as  shown  in  figure  14-10
  herein:
    a.  Adequate  air  circulation may be provided by leaving all edges of
  the wall open with an air gap of at least two inches.
    b. If the wall protector is mounted on a single flat  wall  away  from
  corners,  adequate  air  circulation may be provided by leaving only the
  bottom and top edges or only the side and top edges open with an air gap
  of at least two inches.
    c. Wall protectors that cover two walls in a corner shall be  open  at
  the bottom and top edges with an air gap of at least two inches.
 
                                 TABLE 14-1
          Reduction of Appliance Clearance with Specified Forms of
                      Protection{1,2,3,4,5,6,7,8,9,10}

  Clearance reduction      Maximum allowable    When the required clear-
  system applied to and    reduction in clear-  ance with no protection
  covering all combust-    ance (percent)       is 36 in., the clearances
  ible surfaces within the                      below are the minimum
  distance specified as                         allowable clearance. For
  required clearance with                       other required clearances
  no protection                                 with no protection,
                                                calculate minimum
                                                allowable clearance from
                                                maximum allowable
                                                reduction.{9,10}
 
                                                       As Wall  As Ceiling
                                As Wall   As Ceiling  Protector  Protector
                               Protector   Protector     (in.)     (in.)
                               _________  __________  _________ _________
    (a) 3 1/2 in. thick           33%         __          24        __
  masonry wall without
  ventilated air space.
    (b) 1/2 in. thick             50%         33%         18        24
  noncombustible insul-
  ation board over 1 in.
  glass fiber or mineral
  wool batts without vent-
  ilated air space.
    (c) 0.024 in. (24 gauge)      66%         50%         12        18
  sheet metal over 1 in.
  glass fiber or mineral
  wool batts reinforced
  with wire, or equivalent,
  on rear face with vent-
  ilated air space
    (d) 3 1/2 in. thick           66%         __          12        __
  masonry wall with vent-
  ilated air space
    (e) 0.024 in. (24 gauge)      66%         50%         12        18
  sheet metal with vent-
  ilated air space.
    (f) 1/2 in. noncombustible    66%         50%         12        18
  insulation board with vent-
  ilated air space.
    (g) 0.024 in. (24 gauge)      66%         50%         12        18
  sheet metal with vent-
  ilated air space over
  0.024 in. (24 gauge)
  sheet metal with vent-
  ilated air space.
    (h) 1 in. glass fiber         66%         50%         12        18
  or mineral wool batts
  sandwiched between two
  sheets 0.024 in. (24 gauge)
  sheet metal with vent-
  ilated air space.
 
  Notes:
    {1} Spacers  and  ties shall be of noncombustible material. No spacers
  or ties shall be used directly behind appliance or conductor.

    {2} With all clearance reduction systems using a ventilated air space,
  adequate air circulation shall be provided. There shall be  at  least  2
  in.  between  the  clearance  reduction system and combustible walls and
  ceilings for clearance reduction systems using a ventilated air space.
    {3} Mineral wool batts (blanket or board) shall have a minimum density
  of 8 lb. per ft{3} and have a minimum melting point of 1500°F.
    {4} Insulation  material  used  as  part of clearance reduction system
  shall have a thermal conductivity of 1.0(BTU-In.)/(Sq ft-Hr-°F) or less.
  Insulation board shall be formed of noncombustible material.
    {5} If a single wall connector passes through a masonry wall used as a
  wall shield, there shall be at least 1/2 in.  of  open,  ventilated  air
  space between the connector and the masonry.
    {6} There  shall  be  at  least  2  in.  between the appliance and the
  protector. In no case shall the clearance between the appliance and  the
  wall surface be reduced below that allowed in the table.
    {7} Clearances in front of the loading door and/or ash removal door of
  the appliance shall not be reduced from those in Section 8-6.
    {8} All clearances and thicknesses are minimums: larger clearances and
  thicknesses  are  acceptable.  Clearances are not to be less than 12 in.
  from appliances.
    {9} To  calculate  the  minimum  allowable  clearance,  the  following
  formula  may  be  used:  C{pr} = C{un} x (1-R/100). C{pr} is the minimum
  allowable clearance. C{un} is the required clearance with no protection,
  and R is the maximum allowable reduction in clearance.
    {10} Refer to Figures 14-11 and 14-12  for  other  reduced  clearances
  using materials (a) through (h).
 
  FRONT VIEW -- (See Figure 14-6)
 
  CLEARANCE  TO  COMBUSTIBLE  WALL  WITH  PROTECTION  AS SPECIFIED -- (See
  Figure 14-7)
 
  MASONRY CLEARANCE REDUCTION SYSTEM -- (See Figure 14-8)
 
  MASONRY WALL TIE -- (See Figure 14-9)
 
  WALL PROTECTORS -- (See Figure 14-10)
 
  Wall Protection Using Materials in Table 14-1 -- (See Figure 14-11)
 
  Ceiling Protection Using Materials in Table -- (See Figure 14-12)
 
    (4) All clearances shall be measured from the  outer  surface  of  the
  combustible  materials  to  the nearest point on the surface of the wood
  burning appliance, disregarding any intervening  protection  applied  to
  the combustible materials.
    (5)  All  clearances  provided  between  wood  burning  appliances and
  combustible materials shall be large enough so as to maintain sufficient
  clearance  between  chimney  connectors  and  combustible  materials  as
  required in subchapter fifteen of this chapter.
    (i) Accessories. Factory-built accessories for wood burning appliances
  such  as  heat exchangers, stove mats, floor pads and protection shields
  shall be listed and accepted, and shall be installed in accordance  with
  the terms of their listing and acceptance.