Fantech VHR150 - DETERMINING YOUR AIRFLOW REQUIREMENT; Room Count Method; ASHRAE method

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fantech
Room classification Number of rooms CFM (L/s) CFM Required
Master bedroom x 10 L/s (20 CFM) =
Basement yes or no =
Bedrooms x 5 L/s (10 CFM) =
Living room x 5 L/s (10 CFM) =
Others x 5 L/s (10 CFM) =
Kitchen x 5 L/s (10 CFM) =
Bathroom x 5 L/s (10 CFM) =
Laundry room x 5 L/s (10 CFM) =
Utility room x 5 L/s (10 CFM) =
Total Ventilation Requirements (add last column ) =
if yes add 10 L/s (20 CFM)
if no = 0
1 CFM = 0.47 L/s
1 L/s = 2.13 CFM
Room Count Method
DETERMINING YOUR AIRFLOW REQUIREMENT
ASHRAE method
Ventilation Air requirements
Floor area Bedrooms
0-1 2-3 4-5 6-7 >7
Ft
2
m
2
CFM L/s CFM L/s CFM L/s CFM L/s CFM L/s
< 1500 <139 30 14 45 21 60 28 75 35 90 42
1501-3000 139.1-279 45 21 60 28 75 35 90 42 105 50
3001-4500 279.1-418 60 28 75 35 90 45 105 50 120 57
4501-6000 418.1-557 75 35 90 42 105 50 120 57 135 64
6001-7500 557.1-697 90 42 105 50 120 57 135 64 150 71
>7500 >697 105 50 120 57 135 64 150 71 165 78
* ASHRAE 62.2-2010 Table 4.1, Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings.
Bathroom: If the HRV is going to provide the required local exhaust ventilation for each bathroom with each a continuous 20 CFM
(10 L/s), this ventilation rate can be considered as part of the whole-building ventilation rate.