1. This Subsection is concerned with modeling the energy performance of components, systems and assemblies, including heat gains from internal loads described in Sentence 9.36.5.4.(4), that are addressed in the scope of the prescriptive requirements in Subsections 9.36.2. to 9.36.4. and that are installed in buildings described in Sentence 9.36.1.3.(3).
2. Internal loads other than those described in Sentence 9.36.5.4.(4) shall be excluded from the performance compliance calculations as they relate to
   1. the lighting of unconditioned spaces,
   2. exterior lighting, and
   3. the ventilation of unconditioned spaces.

1. For the purpose of this Subsection, the term "reference house" shall mean a hypothetical replica of the proposed house design using the same energy sources for the same functions and having the same environmental requirements, occupancy, climatic data and operating schedules, but made to comply with all applicable prescriptive requirements of Subsections 9.36.2. to 9.36.4.
2. For the purpose of this Subsection, the term "annual energy consumption" shall mean the annual sum of service water heating and space-conditioning energy consumption of the proposed house design, as calculated in accordance with this Subsection.
3. For the purpose of this Subsection, the term "house energy target" shall mean the annual energy consumption of the reference house, as calculated in accordance with this Subsection.
4. For the purpose of this Subsection, the term "principal ventilation rate" shall mean the normal operating exhaust capacity of the principal ventilation fan as required by Article 9.32.3.3.

1. The performance compliance calculations shall determine
   1. the annual energy consumption of the proposed house, and
   2. the house energy target of a reference house.
2. The annual energy consumption of the proposed house shall not exceed the house energy target of the reference house. (See Note A-9.36.5.3.(2).)
3. In establishing the house energy target, building components, systems and assemblies shall be accounted for in accordance with the prescriptive requirements of Subsections 9.36.2. to 9.36.4. for the climate zone under consideration.
4. In establishing the annual energy consumption, building components, systems and assemblies that are addressed in the scope of the prescriptive requirements of Subsections 9.36.2. to 9.36.4. shall be accounted for for the climate zone under consideration.
5. Where the construction techniques or building components, systems or assemblies used are more energy-efficient than those prescribed by the prescriptive requirements, the performance compliance calculations are permitted to take this increased performance level into account in the determination of the annual energy consumption, provided it can be quantified and is not dependent on occupant interaction.
6. Both the proposed and reference houses shall be modeled using the same climatic data, soil conditions, operating schedules in Article 9.36.5.4. and temperature set-points.

1. Except as provided in Sentence (2), the energy model calculations shall account for the annual energy consumption of systems and equipment required for
   1. space heating,
   2. ventilation,
   3. service water heating, and
   4. where installed, space cooling. (See Note A-9.36.5.4.(1).)
2. Redundant or back-up equipment for the systems and equipment listed in Sentence (1) is permitted to be excluded from the energy model, provided it is equipped with controls and is not required to meet the space-conditioning load of the house. (See Note A-9.36.5.4.(2).)
3. The schedules used in the energy model shall
   1. be based on a time interval not greater than one hour, where the energy model evaluates the performance of the house over hourly intervals, or
   2. be applied in an hourly-bin model then averaged, where the energy model does not evaluate the performance of the house over hourly intervals.
4. The energy model calculations shall account for the loads due to heat gains from occupants, lighting and miscellaneous equipment using the default schedule provided in Table 9.36.5.4. for every day of the year and such loads shall be
   1. multiplied by the following adjustment factors, as applicable:
      1. 1 for a house with or without a secondary suite,
      2. 0.625 for each suite in a residential building containing 2 suites,
      3. 0.606 for each suite in a residential building containing 3 suites, or
      4. 0.598 for each suite in a residential building containing more than 3 suites, and
   2. increased for each hour by 3.58 W per square metre of floor area in common spaces, if applicable.

      
      Table 9.36.5.4.
      Default Schedule for Internal Heat Gain Loads⁽¹⁾
      Forming Part of Sentence 9.36.5.4.(4)

      

      Notes to Table 9.36.5.4.:
      (1) The schedule indicates at what time of day the heat gains from internal loads and hot water draws are present; it does not account for heat gains from exterior lighting and from lighting of unconditioned spaces.

5. The energy model calculations shall account for the following space-heating temperature set-points:
   1. 21°C in all living spaces above the basement,
   2. 19°C in basements and common spaces, and
   3. 15°C in crawl spaces intended to be conditioned spaces.
6. The energy model calculations shall account for a space-cooling temperature set-point of 25°C in all conditioned spaces served by the cooling system.
7. The energy model calculations shall account for a thermostatic control that responds to fluctuations of ±0.5°C from the temperature set-point. (See Note A-9.36.5.4.(7).)
8. If a computer program is used to carry out the compliance calculations, the calculation methods employed in the energy model shall
   1. be used for both the reference and proposed houses, and
   2. be tested in accordance with ANSI/ASHRAE 140, "Evaluation of Building Energy Analysis Computer Programs," with variations in the computer program from the range recommended therein reported in accordance with Division C.
9. The proposed and reference houses shall both be modeled using the same approach and assumptions, except where building components or energy efficiency features are permitted by this Subsection to be different.
10. The energy model calculations shall account for the effect of airtightness in accordance with Sentence 9.36.5.10.(10) or (11), as applicable.
11. The energy model calculations shall account for heat transfer through elements separating conditioned space from unconditioned space, the exterior or the ground.

1. To calculate the effect of heating and cooling consumption, the energy model calculations shall be performed using climatic data measured at time intervals no greater than one hour for one year (8 760 hours) based on the average of at least 10 years of measured data collected at the weather station nearest to the region in which the proposed house is located. (See Note A-9.36.5.5.(1).)
2. For urban regions with several climatic data sets and for locations for which climatic data are not available, the energy model calculations shall be performed using climatic data that best represent the climate at the building site.
3. The energy model calculations shall account for ground reflectance by
   1. increasing ground reflectance due to snow cover in a ratio of 30% without snow cover and 70% with snow cover, or
   2. taking into account changes in ground reflectance throughout the heating season.

1. 1) For each hour of the year, the energy model calculations shall account for heat transfer through wall assemblies, roof-ceiling assemblies, including attics where applicable, and exposed floor assemblies due to the thermal characteristics of the particular assembly and thermal bridging.
2. The following building envelope assemblies and components shall be addressed in the energy model calculations:
   1. above-ground walls and roof-ceiling assemblies,
   2. floors and walls in contact with the ground, and
   3. c) doors, windows and skylights. (See Subsection 9.36.2.)
3. For each wall assembly, fenestration component, roof-ceiling assembly and exposed floor assembly, the energy model calculations shall account for
   1. the area of the interior side of the insulated surface,
   2. emissivity, and
   3. the effective thermal resistance or overall thermal transmittance, as applicable.
4. The energy model calculations shall account for the effect that each assembly in contact with the ground has on below-grade heat transfer due to
   1. the geometry of the foundation,
   2. soil conditions (see Note A-1.1.3.1.(1)), and
   3. the configuration of the insulation.
5. The energy model calculations shall account for heat transfer through fenestration separating conditioned spaces from the outdoors, including skylights, while accounting for both temperature difference and transmission of solar radiation based on
   1. orientation as a function of azimuth and tilt of the surface,
   2. area of frame opening and glazed area,
   3. overall thermal transmittance, and
   4. solar heat gain coefficient.
6. Where the energy model calculations account for the effect of thermal mass, the contents of the house shall be excluded. (See Note A-9.36.5.6.(6).)
7. The energy model calculations shall account for the presence of thermally active walls, floors and ceilings with embedded conditioning systems that form part of the building envelope.
8. Where skylights are installed in the roof, the gross roof area shall be determined in accordance with Sentence 9.36.2.3.(1).
9. Skylights shall be considered to have no shading.
10. The energy model calculations shall account for the effects of exterior permanent and fixed shading only on solar heat gain from fenestration.
11. The ratio of fenestration area to opaque area of doors shall be the same for the proposed and reference houses. (See Note A-9.36.5.6.(11).)

1. The energy model calculations shall account for the energy consumption of each heating, ventilating and, where installed, cooling system for each hour of the year. (See Note A-9.36.5.7.(1).)
2. Each heating system and, where installed, cooling system shall be accounted for separately in the energy model calculations.
3. Conditioned spaces in both the reference and proposed houses shall be modeled as being
   1. heated, where only heating systems are provided in the proposed house,
   2. cooled, where only cooling systems are provided in the proposed house, or
   3. heated and cooled, where complete heating and cooling systems are provided in the proposed house.
4. The performance requirements stated in Table 9.36.3.10. shall be used in the energy model calculations.
5. Where duct and piping losses are accounted for in the energy model calculations, they shall be included for both the proposed and reference houses and calculated the same way for both houses. (See Note A-9.36.5.7.(5).)
6. The same time periods shall be used in the simulation of the operation of the ventilation system for both the proposed and reference houses.
7. During the heating season, any solar and internal heat gains that cause an increase in space temperature beyond 5.5°C above the setpoint shall be
   1. excluded from the energy model calculations, or
   2. calculated as being vented from the house.
8. The energy model calculations shall account for the part-load performance of equipment, including electrical consumption.
9. The energy model calculations shall account for the heat-recovery efficiency of heat-recovery ventilators using a minimum of 2 data test points derived from testing in accordance with Clause 9.36.3.9.(3)(a) or (b), as applicable.

1. The energy model calculations shall account for the energy consumption of all service water heating systems.
2. The performance requirements stated in Table 9.36.4.2. shall be used in the energy model calculations.
3. Where piping or standby losses are accounted for in the energy model calculations, they shall be included for both the proposed and reference houses, including their effect on space heating and cooling, and calculated the same way for both houses.
4. The energy model calculations shall use a supply cold water temperature, in °C, that is
   1. equal to -0.002 (HDD) + 20.3, where HDD < 7 999,
   2. equal to 4.3, where HDD ≥ 8 000, or
   3. determined based on the ground and air temperatures in the climatic data file.
5. The energy model calculations shall use a service water delivery temperature of 55°C. (See Note A-9.36.5.8.(5).)
6. The energy model calculations shall take into account the service water heating use schedule presented in Table 9.36.5.8. using a load of
   1. 225 L/ day for houses with or without a secondary suite, or
   2. 140 L/day per dwelling unit for other types of residential buildings.

Table 9.36.5.8.
Default Schedule of Service Water Heating Use
Forming Part of Sentence 9.36.5.8.(6)

1. Except where permitted by Articles 9.36.5.10. to 9.36.5.12., the energy model calculations for the proposed house shall be consistent with the proposed construction specifications for that house with regard to
   1. fenestration and opaque building envelope assembly type, effective thermal resistance and areas,
   2. HVAC system types and capacities, and
   3. service water heating system types and capacities. (See Note A-9.36.5.9.(1).)

1. Except as provided in Sentences (2) and (3), the energy model calculations for the proposed house shall be consistent with the proposed construction specifications for that house with regard to
   1. the area of the above-ground portion of foundation walls,
   2. the effective thermal resistance of above-ground walls, ceilings below attics, roof assemblies and rim joists,
   3. the maximum overall thermal transmittance of doors, as calculated in accordance with Sentence 9.36.2.2.(3),
   4. the effective thermal resistance of below-ground walls and slabs-on-ground,
   5. exterior walls, roof-ceiling assembly, doors, walls, exposed floors, and floors in contact with the ground,
   6. distribution, orientation and area of fenestration and doors, as calculated in accordance with Article 9.36.2.3.,
   7. solar heat gain coefficient and overall thermal transmittance of fenestration, as calculated in accordance with Sentence 9.36.2.2.(3),
   8. configuration of insulation in assemblies in contact with the ground, and
   9. ieffective thermal resistance of foundation walls.
2. Except for penetrations, slab-on-ground edge insulation and assemblies with embedded heating pipes, where a building envelope component or assembly covers less than 2% of the total area of the assembly type to which it belongs, its thermal characteristics are not required to be calculated as belonging to a distinct assembly, provided the area of the component or assembly is included in an adjacent assembly having the same orientation (See Note A-9.36.5.10.(2).)
3. Building envelope assemblies with the same thermal characteristics and orientation are not required to be calculated as distinct assemblies, provided their area is included in an adjacent assembly.
4. Building envelope assemblies and components separating conditioned space from enclosed unconditioned space shall have a solar heat gain coefficient equal to 0.
5. Except as stated in Sentence 9.36.5.6.(9), the energy model calculations for the proposed house shall account for the effects of exterior permanent and fixed shading devices, including fins, overhangs, and light shelves, on solar heat gain.
6. Where thermal mass is included in the energy model calculations for the proposed house, it shall be set as
   1. the specified mass up to the inside edge of insulation in exterior walls, the mass of interior walls, the mass up to the centre-line of party walls, and the mass of floors, as applicable,
   2. the specified mass of the building envelope assembly, where the energy model calculations include a transient analysis of thermal transfer of the entire building envelope assembly, or
   3. a default value of 0.060 MJ/m²·°C.
7. Exterior walls, roofs and exposed floors shall have a solar absorptance of 0.4.
8. The orientation of the foundation of the proposed house as constructed shall be within 22.5° of the orientation used in the energy model calculations.
9. The airtightness value used in the energy model calculations for the proposed house shall be
   1. 3.2 air changes per hour at 50 Pa pressure differential, where the construction complies with Section 9.25.,
   2. 2.5 air changes per hour at 50 Pa pressure differential, where it can be shown that the air barrier system is constructed in accordance with Subsection 9.25.3. and Articles 9.36.2.9. and 9.36.2.10., or
   3. where airtightness is tested in accordance with Sentence (11),
      1. the number of air changes per hour at 50 Pa pressure differential, and
      2. the equivalent leakage area (see Note A-9.36.5.10.(9)(c)(ii)).
10. A design airtightness shall be assigned for use in the energy model calculations until the actual airtightness has been measured in accordance with Sentence (11).
11. Where measured airtightness is used in the energy model calculations, it shall be determined in accordance with CAN/CGSB-149.10-M, "Determination of the Airtightness of Building Envelopes by the Fan Depressurization Method,"
    1. as written, or
    2. excluding Clause 6.1.6, which allows intentional openings for mechanical equipment to be left unsealed. (See Note A-9.36.5.10.(11).)
12. Where airtightness is determined in accordance with Sentence (11) using air changes per hour, the result obtained at an air pressure differential of 50 Pa shall be used in the energy model calculations.
13. Where airtightness is determined in accordance with Clause (11)(b), its rate shall be adjusted in the energy model calculations to account for air leakage through mechanical equipment.

1. Where multiple HVAC systems serve a single space, the energy model calculations for the proposed house shall call each system in the order of priority established by the system control in the proposed house.
2. Where a heat pump is included in the proposed house, the energy model calculations shall include
   1. the effect of the source temperature on the heat pump's efficiency, and
   2. the temperature at which the heat pump shuts down.
3. Permanent supplementary heating systems that are operated by a thermostat or automatic control shall be included in the energy model calculations for the proposed house.
4. The performance characteristics of the heat-recovery ventilation system of the proposed house shall be as specified at not less than the principal ventilation rate required for a system designed in accordance with Section 9.32.
5. The ventilation system shall be modeled as operating 8 hours a day at the principal ventilation rate.
6. The energy model calculations shall determine the required principal ventilation rate, in L/s, in accordance with Article 9.32.3.3. based on the number of bedrooms in the proposed house.
7. The energy model calculations may include duct and piping losses, taking into account the properties of the specified duct and piping insulation of the proposed house.
8. The energy model calculations shall include a heating system and, where installed, a cooling system sized according to the specifications for the proposed house.
9. The energy model calculations shall include the effect of part-load performance of equipment using
   1. the same modeled part-load performance data used for the reference house as per Clause 9.36.5.15.(6)(a),
   2. the default part-load performance characteristics stated in Clause 9.36.5.15.(6)(b), or
   3. measured data for the specified equipment. (See Note A-9.36.5.11.(9).)
10. Where a heat-recovery ventilator is installed in the proposed house, the energy model calculations shall only account for the recovery of sensible heat using the efficiency ratings in Sentence 9.36.3.9.(3). (See Note A-9.36.5.11.(10).)
11. Except as provided in Sentence (12), where a forced-air system is installed in the proposed house, the energy model calculations shall assume the circulation fan operates when the heating, cooling or principal ventilation system is operating. (See Note A-9.36.5.11.(11).)
12. Where a forced-air system is installed in the proposed house and where the principal ventilation system in the proposed house is a separate, fully ducted ventilation system, the energy model calculations shall assume the circulation fan operates only when the heating or cooling system is operating.
13. Where the proposed house contains multiple HVAC systems, the circulation fan power shall be the sum of the circulation fan power capacity of each system.
14. The ventilation fan power consumption shall be modeled
    1. as being 2.32 W/L/s for each ventilation fan on the exhaust side and, where applicable, on the supply side, or
    2. as specified, where a heat-recovery ventilator is used.
15. Where a forced-air system is installed in the proposed house, the energy model calculations shall determine the flow rate, in L/s, of the circulation fan in the reference house by multiplying the capacity, inW, of the heating system in the proposed house by
    1. 0.0604 for heat pumps, and
    2. 0.0251 for all other types of heating systems.
16. Where a forced-air system is installed in the proposed house, the energy model calculations shall determine the minimum electricity requirement, in W, of the circulation fan by multiplying the flow rate, in L/s, of the circulation fan in the reference house, determined in accordance with Sentence (15), by a factor of 2.30.
17. Where a forced-air system is installed in the proposed house, the flow rate of the circulation fan shall be modeled as being the larger of
    1. the flow rate of the circulation fan of the reference house, determined in accordance with Sentence (15), or
    2. the flow rate of the circulation fan for the forced-air system specified in the design for the proposed house.
18. Except as provided in Sentence (19), where a forced-air system is installed in the proposed house, the power capacity of the circulation fan shall be modeled as specified in the design for the proposed house.
19. Where the design for the proposed house specifies a forced-air system with a circulation fan flow rate that is lower than the flow rate of the circulation fan in the reference house, as determined in accordance with Sentence (15), the electricity capacity, in W, of the circulation fan shall be modeled as being the larger of
    1. the electricity capacity specified for the circulation fan in the proposed forced-air system, or
    2. the minimum circulation fan electricity capacity determined in accordance with Sentence (16).
20. For natural gas-, oil-, propane- and wood-burning heating systems, the energy model calculations shall set the auxiliary electricity requirements, including that of combustion fans, to those specified for the proposed house.

1. The service water heating system used in the energy model calculations shall be sized as specified in the design for the proposed house.
2. The energy model calculations may include
   1. piping losses, and
   2. drain-water heat recovery, provided the calculation of the heat recovered is based on the efficiency of the drain-water heat-recovery unit specified for the proposed house and the energy savings are determined using a drain-water
      1. inlet temperature to the recovery system of 36°C,
      2. flow rate of 9.5 L/min, and
      3. flow that is available for recovery 15 min/day for a house and 10 min/day per suite for a multi-unit residential building with more than 2 suites. (See 2)

1. Except as provided in Sentence (2) and Articles 9.36.5.14. to 9.36.5.16., the energy model calculations for the reference house shall be consistent with the prescriptive requirements of Subsections 9.36.2. to 9.36.4. with regard to
   1. fenestration and opaque building envelope assembly types and areas,
   2. HVAC system types and capacities, and
   3. service water heating system types and capacities. (See Note A-9.36.5.9.(1).)
2. The energy model calculations for the reference house shall include the same values as those used for the proposed house with regard to
   1. floor area,
   2. heated volume, and
   3. number and types of rooms.

1. The energy model calculations for the reference house shall include the same values as those used for the proposed house with regard to
   1. the gross area of above-ground portion of foundation walls,
   2. soil conditions,
   3. the orientation of the foundation, and
   4. the ratio of fenestration area to opaque area of doors.
2. The energy model calculations for the reference house shall use the following set values:
   1. 0.060 MJ/m2·°C for thermal mass,
   2. a solar absorptance of 0.4 for the exterior walls, roofs and exposed floors,
   3. 0.26 for the solar heat gain coefficient of fenestration, and
   4. 2.5 air changes per hour at 50 Pa pressure differential for airtightness.
3. The effective thermal resistance and overall thermal transmittance values, as applicable, used in the energy model calculations for the reference house shall be determined for the applicable heating degree-day zone in accordance with
   1. Table 9.36.2.6.-A for walls, ceilings below attics, roof assemblies and rim joists,
   2. Table 9.36.2.7.-A for doors, and
   3. Table 9.36.2.8.-A for below-grade walls and slabs-on-ground.
4. Except as provided in Sentences (5) and (6), the exterior walls, roof-ceiling assembly, doors, walls, exposed floors, and floors of the reference house that are in contact with the ground shall have the same area as those of the proposed house.
5. The area and orientation of fenestration and doors of the reference house shall be modeled as being equally distributed on all sides of the house.
6. The gross wall area and the area of fenestration and doors of the reference house shall be determined in accordance with Article 9.36.2.3.
7. Windows and other glazed components in the reference house shall have a maximum overall thermal transmittance as required in Table 9.36.2.7.-A for the applicable heating degree-day category.
8. The configuration of insulation in assemblies of the reference house that are in contact with the ground shall be modeled as conforming to Article 9.36.2.8.
9. Foundation walls shall be modeled using the applicable effective thermal resistance values in Table 9.36.2.8.-A and as conforming to Sentence 9.36.2.8.(2).
10. The fenestration and door area to gross wall area ratio (FDWR) of the reference house shall be
    1. for houses containing 1 or 2 dwelling units,
       1. as per the proposed house, where its FDWR is between 17% and 22%,
       2. 17%, where the FDWR of the proposed house is less than 17%, or
       3. 22%, where the FDWR of the proposed house is greater than 22%, and
    2. for buildings of residential occupancy containing more than 2 dwelling units,
       1. the FDWR determined in Clause (a) for the areas determined in accordance with Sentence 9.36.2.3.(2) and, where the FDWR determined in accordance with the calculation in Sentence 9.36.2.3.(3) only does not exceed 40%, or
       2. 40% of the gross wall area enclosing conditioned space where the area of fenestration and doors is greater than 40% of the gross wall area enclosing conditioned space determined in accordance with Sentence 9.36.2.3.(2). (See Note A-9.36.5.14.(10).)

1. Where multiple HVAC systems serve a single space, the energy model calculations for the reference house shall use the same order of priority as that used for the proposed house. (See Sentence 9.36.5.11.(1).)
2. The energy model calculations for the reference house shall include the same features as those used for the proposed house with regard to
   1. the principal heating and cooling energy sources, which are gas, electricity, oil, propane, wood or a heat pump,
   2. the primary and secondary energy sources, which are gas, electricity, oil, propane, wood or a heat pump, and
   3. the ventilation rate (see Sentence 9.36.5.11.(6)).
3. Except as required in Sentence 9.36.3.8.(1), the reference house shall be modeled without a heat-recovery ventilator.
4. The ventilation system shall be modeled as operating 8 hours a day.
5. The heating system and, where installed, the cooling system shall be sized in accordance with Article 9.33.5.1. with regard to total heat output capacity and nominal cooling capacity. (See Note A-9.36.5.15.(5).)
6. The part-load performance of HVAC equipment in the reference house shall be calculated using
   1. modeled part-load performance characteristics, where applicable, or
   2. the performance values for each type of system multiplied by an adjustment factor from Table 9.36.5.15.-A, 9.36.5.15.-B or 9.36.5.15.-C as follows:
      1. for furnaces, by multiplying the furnace steady-state efficiency by the adjustment factor given in Table 9.36.5.15.-A,
      2. for heat pumps and air conditioners, by multiplying the heat pump steady-state coefficient of performance by the adjustment factor given in Table 9.36.5.15.-B, and
      3. for boilers, combination space-heating and service water heating systems, and integrated mechanical systems, by multiplying the net-full-load heating efficiency by the adjustment factor given in Table 9.36.5.15.-C. (See Note A-9.36.5.15.(6).)

         
         Table 9.36.5.15.-A
         Part-Load Adjustment Factors for Furnaces
         Forming Part of Subclause 9.36.5.15.(6)(b)(i)

         

         
         Table 9.36.5.15.-B
         Part-Load Adjustment Factors for Heat Pumps and Air Conditioners
         Forming Part of Subclause 9.36.5.15.(6)(b)(ii)

         

         
         Table 9.36.5.15.-C
         Part-Load Adjustment Factors for Boilers, Combination Systems and Integrated Mechanical Systems
         Forming Part of Subclause 9.36.5.15.(6)(b)(iii)

         

         
         Notes to Table 9.36.5.15.-C:
         (1) Integrated mechanical systems perform all three functions of space-heating, water-heating and heat-recovery ventilation.
         (2) The part-load characteristics of these types of systems shall not be accounted for in the energy model calculations.
         

7. The performance of the HVAC equipment in the reference house shall be modeled
   1. as conforming to Table 9.36.3.10. for the corresponding type, fuel source and capacity of equipment in the proposed house, or
   2. where the HVAC equipment for the proposed house is not addressed in Table 9.36.3.10., as a gas warm-air furnace with a minimum performance rating of 92% annual fuel utilization efficiency.
8. Where a heat-recovery ventilator is installed in the reference house, the energy model calculations shall only account for the recovery of sensible heat using the efficiency ratings in Sentence 9.36.3.9.(3). (See Note A-9.36.5.15.(8).)
9. The energy model calculations shall assume all ventilation and circulation fans required to be modeled in the reference house are equipped with permanent-split capacitor (PSC) motors.
10. Where a forced-air system is installed in the reference house, the energy model calculations shall assume the circulation fan operates when the heating, cooling or principal ventilation system is called for.
11. Where the reference house contains multiple HVAC systems, the circulation fan power shall be the sum of the circulation fan power capacity of each system.
12. The principal ventilation flow rate, in L/s, prescribed in Section 9.32. shall be multiplied by 2.32 W/L/s to determine the ventilation fan power capacity, in W, to be used in the energy model calculations for each fan on the exhaust side and, where applicable, on the supply side.
13. Where a heat-recovery ventilator is required in the reference house in accordance with Article 9.36.3.8., the ventilation flow rate, in L/s, in the zone served by the pool or hot tub shall be multiplied by 4.18 W/L/s to determine the heat-recovery ventilator power, in W, to be used in the energy model calculations.
14. Where a forced-air system is installed in the reference house, the system's capacity, in W, shall be multiplied by one of the following factors to determine the circulation fan flow rate, in L/s:
    1. 0.0604 for heat pumps, and
    2. 0.0251 for all other types of heating systems.
15. Where a forced-air system is installed in the reference house, the circulation fan flow rate, in L/s, shall be multiplied by 2.30 W/L/s to determine the circulation fan power capacity, in W.
16. For natural gas-, oil-, propane- and wood-burning heating systems, the energy model calculations shall set the auxiliary electricity capacity, including that of combustion fans, to 208 W during operation.

1. The energy source of the reference house's service water heating system, which is gas, electricity, oil, propane, wood or a heat pump, shall be the same as that for the system in the proposed house.
2. The service water heating system in the reference house shall be sized in accordance with Subsection 9.31.6. with regard to output capacity.
3. Except as required by Table 9.36.5.16., the performance of the service water heating equipment in the reference house shall be modeled as conforming to Table 9.36.4.2. for the energy source, capacity and type of service water heating equipment in the proposed house.

Table 9.36.5.16.
Performance of Service Water Heating (SWH) Equipment in the Reference House
Forming Part of Sentence 9.36.5.16.(3)

Notes to Table 9.36.5.16.:
(1) Consistent with the U.S. Congress "National Appliance Energy Conservation Act of 1987."