6
These are the two most common methods used to evaluate the ventilation needs of a house:
CSA F326 and Canadian Building Code:
• High speed:
10 cfm per room
20 cfm for the master bedroom and the basement
• Low speed:
40-60% of high speed
ASHRAE Standard 62-2001:
• 0.35 air change per hour
Refer to ventilation code of your area to determine which method to use.
Example:
2. Sizing
M
as
ter
b
edroom
Bedroom no.1
Kitchen
B
as
ement
Bedroom
no. 2
Bedroom
no.
3
Living room
B
a
throom
no
.
3
Dining room
VH0021A
F
a
mily room
B
a
throom
no
. 1
B
a
throom
no
. 2
L
au
ndry
room
1320 ft²
1320 ft²
CSA F326
Kitchen
(10
cfm
)
Dining room
(10
cfm
)
Living room
(10
cfm
)
Family room
(10
cfm
)
Master bedroom
(20
cfm
)
Bedroom no. 1
(10
cfm
)
Bedroom no. 2
(10
cfm
)
Bedroom no. 3
(10
cfm
)
Bathroom no. 1
(10
cfm
)
Bathroom no. 2
(10
cfm
)
Bathroom no. 3
(10
cfm
)
Laundry room
(10
cfm
)
Basement
(20
cfm
)
Total 150
cfm
ASHRAE Standard 62-1989
Volume of basement
10560 ft³
Volume of main floor
10560 ft³
Volume of second floor
10560 ft³
Total volume
31680 ft³
x 0.35/h
11090 ft³/h
÷ 60 (min/h)
Total 185
cfm
1320 ft²
Second floor
Main floor
Basement
