Proposed changes developed for the 2025 edition of the National Building Code of Canada (NBC) and National Energy Code of Canada for Buildings (NECB) introduce new abbreviated terms to quantify operational greenhouse gas (GHG) emissions. While these abbreviations, such as “CO2e”, “GHG”, “GJ” and “kWh”, are commonly used in the industry, they are not assigned meaning in the NBC and NECB, which could result in confusion leading to improper application of Code provisions.
Providing the meaning of new abbreviated terms used in the technical requirements of the NBC and NECB to quantify operational GHG emissions would
A
a
Btu
cfm
CH
CO2e
COP
°
°C
°F
db
Ec
Et
EER
EF
ft.
g
GHG
GJ
gpm
>
≥
h
HVAC
IEER
IPLV
K
kg
kJ
kVA
kW
kWh
<
≤
L
lb.
LPD
lx
m
max.
MBH
min.
min
mm
No.
o.c.
Pa
%
R
RSI
s
SCOP
SEER
SL
Δt
US gal.
U-value
V
Vt
W
wb
1 in 2
cm
CO2e
°
°C
dBA
diam
g
GHG
GJ
h
HDD
HVAC
Hz
J
K
kg
kN
kPa
kW
kWh
L
lx
m
M
max.
min.
min
MJ
mm
MPa
N
n/a
ng
No.
o.c.
OSB
PM
ppb
ppm
R
RSI
s
W
%
µg
µm
U-value
This proposed change would add consistency and eliminate any potential ambiguity in the interpretation of various NBC and NECB requirements containing the abbreviations.
Providing the meaning of the abbreviations would not have a negative impact on building design; and, therefore, should not result in any additional costs in the design of a particular project.
This proposed change increases clarity and consistency, thereby reducing ambiguity in Code interpretation. There should not be any resulting enforcement implications.
Designers, engineers, architects, builders and building officials.