Page | 1
15.8 - CONTRACTOR - VENTILATION
QUESTIONS WITH DETAILED VERIFIED
ANSWERS
(E) Explain how stack effect and wind can affect the ventilation of a
building in Quebec. Ans: Stack effects are caused by the difference in air
density between the inside and outside of a building, creating vertical
movement. Warm air rises at 0.24 CFM/ft (0.73 m³/min/m) of height for
each °F (°C) of difference. Wind creates positive pressure zones on
exposed facades and negative on opposite sides, influencing air
movement through the building envelope. According to the Quebec
Building Code, these effects must be considered when designing
ventilation systems.
(M) What are the units of measurement used for air flow, pressure, and
velocity in ventilation systems in Quebec? Ans: For air flow: CFM
(ft³/min) or L/s (liters/second); for pressure: PSI or inches of water
(kPa); for velocity: ft/min (m/min). In Quebec, according to CAN/CSA-
F326-M standard, both unit systems (imperial and metric) are used, with
imperial as the primary reference and metric in parentheses in technical
documents and specifications.
(M) In a residential ventilation system in Quebec, how is the minimum
fresh air flow requirement calculated according to current standards?
Ans: According to CAN/CSA-F326-M standard, the minimum fresh air
flow for a residence in Quebec is calculated based on the number of
rooms and occupants: 0.3 air changes per hour or 7.5 CFM (3.5 L/s) per
person, whichever is greater. For a typical 3-bedroom home, this
translates to approximately 100-160 CFM (47-75 L/s) depending on
square footage and ceiling height.
(D) A commercial kitchen ventilation system in Montreal requires
installation of a Type I hood. What are the specific clearance
requirements for combustible materials according to NFPA 96? Ans:
According to NFPA 96, for a Type I hood installation in a commercial
kitchen in Montreal, the minimum clearance between the hood and
combustible materials must be 18 inches (457 mm). This clearance can
, Page | 2
be reduced when using approved fire-resistant barriers. Hoods must
maintain 78 inches (1980 mm) above the finished floor for accessibility.
The Quebec Construction Code also requires that the hood must extend a
minimum of 6 inches (152 mm) beyond all cooking appliances on all open
sides.
(M) Calculate the duct sizing for a ventilation system serving a 200 ft²
(18.6 m²) office space in Quebec City if the required air change rate is 6
ACH and maximum allowable air velocity is 800 ft/min (244 m/min).
Ans: For a 200 ft² (18.6 m²) office with 9 ft (2.7 m) ceiling height, the
volume is 1,800 ft³ (51 m³). At 6 ACH, the required airflow is 180 CFM
(85 L/s). Using the equation A = Q/V, where A is duct area, Q is airflow
rate, and V is velocity: A = 180 CFM / 800 ft/min = 0.225 ft² (0.021 m²).
For a round duct, diameter = √(4A/π) = √(4×0.225/π) = 0.535 ft or 6.4
inches (163 mm). According to SMACNA standards adopted in Quebec, an
8-inch (200 mm) diameter duct would be appropriate.
(E) What are the requirements for fire damper installation in ventilation
ducts that penetrate fire-rated assemblies in Quebec? Ans: In Quebec,
according to the CCQ Chapter I, Building Code, fire dampers must be
installed where ducts penetrate fire-rated assemblies. They must have a
fire-resistance rating at least equal to that of the penetrated assembly.
Installation requires 165°F (74°C) fusible links, accessibility for inspection
and maintenance, and vertical mounting within 4 inches (100 mm) of the
fire separation. Each fire damper must be tested after installation and
labeled with ULC approval. Specific documentation of installation must be
provided to building officials.
(M) Describe the required components of a mechanical ventilation system
for a single-family home in Quebec. Ans: A mechanical ventilation
system for a single-family home in Quebec, according to CAN/CSA-F326-
M, must include: a principal ventilation fan (minimum capacity based on
floor area, typically 50-100 CFM or 24-47 L/s); fresh air intake with
insulated duct; exhaust points in bathrooms and kitchen; distribution
ductwork; controls (manual or automated); and air filters. Heat recovery
ventilators (HRVs) are strongly recommended for energy efficiency,
especially in colder regions of Quebec. The system must provide 0.3 air
changes per hour minimum and maintain indoor humidity between 30-
55%.
, Page | 3
(D) A commercial building in Laval has an HVAC system that seems to be
creating negative pressure, causing difficulty in opening exterior doors.
What calculations would you perform to determine the required makeup
air? Ans: To calculate required makeup air for the negatively pressurized
building in Laval: First measure total exhaust airflow (CFM or L/s) from
all exhaust fans, hoods, and equipment. Then measure total supply
airflow. The difference represents the building's air deficit. For proper
balance: Makeup Air = Total Exhaust - Total Supply. According to Quebec
regulations, building pressure should be slightly positive or neutral,
maintaining 0.01-0.03 inches water column (2.5-7.5 Pa). For commercial
buildings, makeup air systems must provide at least 85% of exhausted
air according to ASHRAE standards adopted in Quebec's Construction
Code.
(M) What are the testing and balancing requirements for a newly installed
ventilation system in a Quebec commercial building? Ans: Testing and
balancing requirements for a new commercial ventilation system in
Quebec include: verification that the system meets design specifications
per SMACNA standards; measurement and adjustment of airflows at all
terminals to within ±10% of design values; testing of all fire and smoke
dampers; verification of outdoor air quantities; testing of control
systems; sound level measurement; fan performance verification; and
documentation of all results. Final reports must be certified by qualified
technicians and submitted as part of the building commissioning process
according to the Quebec Construction Code and ASHRAE guidelines.
(E) Explain the concept of heat recovery in ventilation systems and why
it's particularly important in Quebec's climate. Ans: Heat recovery in
ventilation systems captures thermal energy from exhaust air and
transfers it to incoming fresh air. In Quebec's cold climate (with
temperatures frequently below -4°F/-20°C), this is particularly important
for energy efficiency. Heat Recovery Ventilators (HRVs) can recover 60-
80% of heat energy, reducing heating costs by 10-20%. Energy Recovery
Ventilators (ERVs) also transfer moisture, helping maintain indoor
humidity. Quebec's Energy Efficiency Regulations strongly recommend
heat recovery systems with minimum 55% sensible effectiveness. These
systems typically provide payback periods of 3-5 years in Quebec's
climate zones.
, Page | 4
(M) A restaurant kitchen in Quebec City requires a ventilation system.
What are the minimum exhaust airflow requirements according to NFPA
96? Ans: According to NFPA 96 and Quebec's Construction Code, kitchen
exhaust requirements are based on cooking equipment and hood
dimensions. For a typical Type I hood, the minimum exhaust rate is 150
CFM/ft² (762 L/s/m²) of hood opening for wall-mounted hoods and 100
CFM/ft² (508 L/s/m²) for island hoods. For a 10 ft × 4 ft (3 m × 1.2 m)
wall-mounted hood, the minimum exhaust would be 6,000 CFM (2,832
L/s). Heavy-duty cooking equipment requires higher rates up to 300
CFM/ft² (1,524 L/s/m²). Makeup air must be provided at 95-100% of
exhaust volume.
(D) Design a ventilation system for a 400 ft² (37 m²) cannabis growing
facility in Quebec that complies with all relevant regulations. Ans: For a
400 ft² (37 m²) cannabis growing facility in Quebec, the ventilation
system must include: exhaust capacity of 30 air changes per hour (2,000
CFM or 944 L/s minimum); carbon filtration for odor control as required
by municipal regulations; HEPA filtration for incoming air (MERV 13
minimum); negative room pressure of -0.01 to -0.02 inches water
column (-2.5 to -5 Pa); dehumidification capacity to maintain 40-50%
relative humidity; sealed ductwork to prevent air leakage; separate
ventilation zones for growing vs. processing areas; and monitoring
systems. All installations must comply with Quebec's Construction Code
and ASHRAE 62.1 standards for indoor air quality.
(E) What are the main requirements for radon mitigation systems in new
residential construction in Quebec? Ans: Radon mitigation systems in
new Quebec residential construction must meet Health Canada's
guidelines and Quebec Construction Code requirements. New homes
must include: a sub-slab depressurization rough-in (4-inch/100 mm
perforated pipe under the basement slab); a sealed soil gas barrier (6-
mil/0.15 mm polyethylene); sealed and gasketted sump pit covers;
sealed penetrations through foundation walls and floors; and a labeled 3-
inch (75 mm) standpipe extending from the sub-slab system to the attic
for potential future fan installation. These measures are particularly
important in high-radon areas of Quebec like the Laurentians and Eastern
Townships where levels can exceed 200 Bq/m³.
(M) Calculate the heating load for a ventilation system that delivers 1,000
CFM (472 L/s) of fresh air at -4°F (-20°C) to a space maintained at 70°F
15.8 - CONTRACTOR - VENTILATION
QUESTIONS WITH DETAILED VERIFIED
ANSWERS
(E) Explain how stack effect and wind can affect the ventilation of a
building in Quebec. Ans: Stack effects are caused by the difference in air
density between the inside and outside of a building, creating vertical
movement. Warm air rises at 0.24 CFM/ft (0.73 m³/min/m) of height for
each °F (°C) of difference. Wind creates positive pressure zones on
exposed facades and negative on opposite sides, influencing air
movement through the building envelope. According to the Quebec
Building Code, these effects must be considered when designing
ventilation systems.
(M) What are the units of measurement used for air flow, pressure, and
velocity in ventilation systems in Quebec? Ans: For air flow: CFM
(ft³/min) or L/s (liters/second); for pressure: PSI or inches of water
(kPa); for velocity: ft/min (m/min). In Quebec, according to CAN/CSA-
F326-M standard, both unit systems (imperial and metric) are used, with
imperial as the primary reference and metric in parentheses in technical
documents and specifications.
(M) In a residential ventilation system in Quebec, how is the minimum
fresh air flow requirement calculated according to current standards?
Ans: According to CAN/CSA-F326-M standard, the minimum fresh air
flow for a residence in Quebec is calculated based on the number of
rooms and occupants: 0.3 air changes per hour or 7.5 CFM (3.5 L/s) per
person, whichever is greater. For a typical 3-bedroom home, this
translates to approximately 100-160 CFM (47-75 L/s) depending on
square footage and ceiling height.
(D) A commercial kitchen ventilation system in Montreal requires
installation of a Type I hood. What are the specific clearance
requirements for combustible materials according to NFPA 96? Ans:
According to NFPA 96, for a Type I hood installation in a commercial
kitchen in Montreal, the minimum clearance between the hood and
combustible materials must be 18 inches (457 mm). This clearance can
, Page | 2
be reduced when using approved fire-resistant barriers. Hoods must
maintain 78 inches (1980 mm) above the finished floor for accessibility.
The Quebec Construction Code also requires that the hood must extend a
minimum of 6 inches (152 mm) beyond all cooking appliances on all open
sides.
(M) Calculate the duct sizing for a ventilation system serving a 200 ft²
(18.6 m²) office space in Quebec City if the required air change rate is 6
ACH and maximum allowable air velocity is 800 ft/min (244 m/min).
Ans: For a 200 ft² (18.6 m²) office with 9 ft (2.7 m) ceiling height, the
volume is 1,800 ft³ (51 m³). At 6 ACH, the required airflow is 180 CFM
(85 L/s). Using the equation A = Q/V, where A is duct area, Q is airflow
rate, and V is velocity: A = 180 CFM / 800 ft/min = 0.225 ft² (0.021 m²).
For a round duct, diameter = √(4A/π) = √(4×0.225/π) = 0.535 ft or 6.4
inches (163 mm). According to SMACNA standards adopted in Quebec, an
8-inch (200 mm) diameter duct would be appropriate.
(E) What are the requirements for fire damper installation in ventilation
ducts that penetrate fire-rated assemblies in Quebec? Ans: In Quebec,
according to the CCQ Chapter I, Building Code, fire dampers must be
installed where ducts penetrate fire-rated assemblies. They must have a
fire-resistance rating at least equal to that of the penetrated assembly.
Installation requires 165°F (74°C) fusible links, accessibility for inspection
and maintenance, and vertical mounting within 4 inches (100 mm) of the
fire separation. Each fire damper must be tested after installation and
labeled with ULC approval. Specific documentation of installation must be
provided to building officials.
(M) Describe the required components of a mechanical ventilation system
for a single-family home in Quebec. Ans: A mechanical ventilation
system for a single-family home in Quebec, according to CAN/CSA-F326-
M, must include: a principal ventilation fan (minimum capacity based on
floor area, typically 50-100 CFM or 24-47 L/s); fresh air intake with
insulated duct; exhaust points in bathrooms and kitchen; distribution
ductwork; controls (manual or automated); and air filters. Heat recovery
ventilators (HRVs) are strongly recommended for energy efficiency,
especially in colder regions of Quebec. The system must provide 0.3 air
changes per hour minimum and maintain indoor humidity between 30-
55%.
, Page | 3
(D) A commercial building in Laval has an HVAC system that seems to be
creating negative pressure, causing difficulty in opening exterior doors.
What calculations would you perform to determine the required makeup
air? Ans: To calculate required makeup air for the negatively pressurized
building in Laval: First measure total exhaust airflow (CFM or L/s) from
all exhaust fans, hoods, and equipment. Then measure total supply
airflow. The difference represents the building's air deficit. For proper
balance: Makeup Air = Total Exhaust - Total Supply. According to Quebec
regulations, building pressure should be slightly positive or neutral,
maintaining 0.01-0.03 inches water column (2.5-7.5 Pa). For commercial
buildings, makeup air systems must provide at least 85% of exhausted
air according to ASHRAE standards adopted in Quebec's Construction
Code.
(M) What are the testing and balancing requirements for a newly installed
ventilation system in a Quebec commercial building? Ans: Testing and
balancing requirements for a new commercial ventilation system in
Quebec include: verification that the system meets design specifications
per SMACNA standards; measurement and adjustment of airflows at all
terminals to within ±10% of design values; testing of all fire and smoke
dampers; verification of outdoor air quantities; testing of control
systems; sound level measurement; fan performance verification; and
documentation of all results. Final reports must be certified by qualified
technicians and submitted as part of the building commissioning process
according to the Quebec Construction Code and ASHRAE guidelines.
(E) Explain the concept of heat recovery in ventilation systems and why
it's particularly important in Quebec's climate. Ans: Heat recovery in
ventilation systems captures thermal energy from exhaust air and
transfers it to incoming fresh air. In Quebec's cold climate (with
temperatures frequently below -4°F/-20°C), this is particularly important
for energy efficiency. Heat Recovery Ventilators (HRVs) can recover 60-
80% of heat energy, reducing heating costs by 10-20%. Energy Recovery
Ventilators (ERVs) also transfer moisture, helping maintain indoor
humidity. Quebec's Energy Efficiency Regulations strongly recommend
heat recovery systems with minimum 55% sensible effectiveness. These
systems typically provide payback periods of 3-5 years in Quebec's
climate zones.
, Page | 4
(M) A restaurant kitchen in Quebec City requires a ventilation system.
What are the minimum exhaust airflow requirements according to NFPA
96? Ans: According to NFPA 96 and Quebec's Construction Code, kitchen
exhaust requirements are based on cooking equipment and hood
dimensions. For a typical Type I hood, the minimum exhaust rate is 150
CFM/ft² (762 L/s/m²) of hood opening for wall-mounted hoods and 100
CFM/ft² (508 L/s/m²) for island hoods. For a 10 ft × 4 ft (3 m × 1.2 m)
wall-mounted hood, the minimum exhaust would be 6,000 CFM (2,832
L/s). Heavy-duty cooking equipment requires higher rates up to 300
CFM/ft² (1,524 L/s/m²). Makeup air must be provided at 95-100% of
exhaust volume.
(D) Design a ventilation system for a 400 ft² (37 m²) cannabis growing
facility in Quebec that complies with all relevant regulations. Ans: For a
400 ft² (37 m²) cannabis growing facility in Quebec, the ventilation
system must include: exhaust capacity of 30 air changes per hour (2,000
CFM or 944 L/s minimum); carbon filtration for odor control as required
by municipal regulations; HEPA filtration for incoming air (MERV 13
minimum); negative room pressure of -0.01 to -0.02 inches water
column (-2.5 to -5 Pa); dehumidification capacity to maintain 40-50%
relative humidity; sealed ductwork to prevent air leakage; separate
ventilation zones for growing vs. processing areas; and monitoring
systems. All installations must comply with Quebec's Construction Code
and ASHRAE 62.1 standards for indoor air quality.
(E) What are the main requirements for radon mitigation systems in new
residential construction in Quebec? Ans: Radon mitigation systems in
new Quebec residential construction must meet Health Canada's
guidelines and Quebec Construction Code requirements. New homes
must include: a sub-slab depressurization rough-in (4-inch/100 mm
perforated pipe under the basement slab); a sealed soil gas barrier (6-
mil/0.15 mm polyethylene); sealed and gasketted sump pit covers;
sealed penetrations through foundation walls and floors; and a labeled 3-
inch (75 mm) standpipe extending from the sub-slab system to the attic
for potential future fan installation. These measures are particularly
important in high-radon areas of Quebec like the Laurentians and Eastern
Townships where levels can exceed 200 Bq/m³.
(M) Calculate the heating load for a ventilation system that delivers 1,000
CFM (472 L/s) of fresh air at -4°F (-20°C) to a space maintained at 70°F
