Appendix A — Division B
Explanatory Material
BC2012 2012-01-01 R1
A-10.2.1.1.(3) DeletedAlternatives to Prescribed Insulation Requirements
Computer modelling can provide options to the requirements of Table 10.2.1.1.A by considering factors other than insulation that impact energy efficiency and greenhouse
gas emissions. These include items such as higher fenestration efficiency, more efficient
Heating, Ventilating, Air Conditioning (HVAC) systems, renewable energy systems and
reduced envelope air leakage from what is required or is common practice. The Natural
Resources Canada EnerGuide Rating System program uses Hot2000 Version 10 for modelling.
It can be downloaded at:
http://canmetenergy.nrcan.gc.ca/software-tools/hot2000/84. The Ministry of Energy, Mines and Petroleum Resources can provide assistance in
determining options to the prescriptive insulation requirements of Table 10.2.1.1.A.
TEDI does not include receptacle loads and energy use from unusual uses such as spas
and computer server rooms.
Although the total energy use intensity and thermal energy demand intensity are not
required for NECB conformance, they must still be calculated in conformance with
Article 10.2.3.4.
and reported in accordance with
Subsection 2.2.9. of Division C.
Notwithstanding the requirements of Part 8 of the NECB, a reference building and building
energy target are not required for compliance with the requirements of Steps 2 to
4 in
Article 10.2.3.3. The performance requirements of
Table 10.2.3.3.A and
Table 10.2.3.3.B are used to determine compliance.
Air Leakage Rate in Energy Model Calculations
The requirement to account for the air leakage rate as tested in all energy model
calculations, other than for Step 1 buildings, supersedes the NECB, which permits
an assumed air leakage value of 0.25 L/(s⋅m2) to be used for energy model calculations. For buildings that must conform to the
requirements of any of Steps 2 to 4, higher than expected air leakage may require
the building design to be altered and the energy model calculations to be repeated.
Alternatively, the air leakage rate could be retested after making alterations to
the air barrier system to attain the desired air leakage rate.
Air Leakage Rate in Energy Model Calculations for Step 1
Although the air leakage rate as tested of the building need not be used for the purposes
of conforming with Part 8 of the NECB and
Sentence 10.2.3.4.(2),
Article 2.2.9.1. of Division C requires that the air leakage rate as tested be used in the calculation of the total
energy use intensity and thermal energy demand intensity for reporting purposes on
the drawings and specifications. This will typically require Step 1 energy model calculations
to be redone after the airtightness test. It is not intended that the results of the
airtightness test for buildings that must conform to the requirements of Step 1 influence
the compliance of the building with
Article 10.2.3.3.Air Leakage Rate
The air leakage rate of 0.25 L/(s⋅m2), which is a typical infiltration rate at 5 Pa, is for calculation purposes and may
not reflect the real rate encountered under actual operating conditions; it is based
on assumed typical operating pressure differentials.
The intent of this testing is to quantify the airtightness level of the air barrier
system, not airtightness of the building at in-service operating conditions.
BC2012 2017-04-07 R11
Appendix A — Division B
TEDI does not include receptacle loads and energy use from unusual uses such as spas
and computer server rooms.
Although the total energy use intensity and thermal energy demand intensity are not
required for NECB conformance, they must still be calculated in conformance with Article
10.2.3.410.3.1.4. and reported in accordance with Subsection 2.2.9. of Division C.
Notwithstanding the requirements of Part 8 of the NECB, a reference building and building
energy target are not required for compliance with the requirements of Steps 2 to
4 in Article 10.2.3.3. The performance requirements of Table 10.2.3.3.A and Table 10.2.3.3.B are used to determine compliance.
Air Leakage Rate in Energy Model Calculations The requirement to account for the air leakage rate as tested in all energy model
calculations, other than for Step 1 buildings, supersedes the NECB, which permits
an assumed air leakage value of 0.25 L/(s⋅m2) to be used for energy model calculations. For buildings that must conform to the
requirements of any of Steps 2 to 4, higher than expected air leakage may require
the building design to be altered and the energy model calculations to be repeated.
Alternatively, the air leakage rate could be retested after making alterations to
the air barrier system to attain the desired air leakage rate.
Air Leakage Rate in Energy Model Calculations for Step 1
Although the air leakage rate as tested of the building need not be used for the purposes
of conforming with Part 8 of the NECB and Sentence 10.2.3.4.(2), Article 2.2.9.1. of Division C requires that the air leakage rate as tested be used in the calculation of the total
energy use intensity and thermal energy demand intensity for reporting purposes on
the drawings and specifications. This will typically require Step 1 energy model calculations
to be redone after the airtightness test. It is not intended that the results of the
airtightness test for buildings that must conform to the requirements of Step 1 influence
the compliance of the building with Article 10.2.3.3.
The air leakage rate of 0.25 L/(s⋅m
2), which is a typical infiltration rate at 5 Pa, is for calculation purposes and may
not reflect the real rate encountered under actual operating conditions; it is based
on assumed typical operating pressure differentials.
Although the air leakage rate as tested of the building need not be used for the purposes
of conforming with Part 8 of the NECB and Sentence 10.2.3.4.(2), Article 2.2.9.1. of Division C requires that the air leakage rate as tested be used in the calculation of the total
energy use intensity and thermal energy demand intensity for reporting purposes on
the drawings and specifications. This will typically require Step 1 energy model calculations
to be redone after the airtightness test. It is not intended that the results of the
airtightness test for buildings that must conform to the requirements of Step 1 influence
the compliance of the building with Article 10.2.3.3.
The air leakage rate of 0.25 L/(s⋅m2), which is a typical infiltration rate at 5 Pa, is for calculation purposes and may
not reflect the real rate encountered under actual operating conditions; it is based
on assumed typical operating pressure differentials.
The intent of this testing is to quantify the airtightness level of the air barrier
system, not airtightness of the building at in-service operating conditions.