CFM Calculator
| Room Dimensions | |
|---|---|
| Volume: | |
| OR | |
| Height: | |
| Floor Area: | |
| Airflow Requirements | |
| Air changes per hour (ACH): | |
CFM (Cubic Feet per Minute) is a unit of measurement used to quantify the amount of air flow in a given space. It represents the volume of air that is circulated or exchanged in one minute. Understanding the CFM requirements is essential for ensuring proper ventilation and maintaining good air quality in various environments.
The air changes per hour (ACH) is a significant factor in determining the appropriate CFM rate. ACH refers to the number of times the air within a room or building is replaced with fresh air within one hour. The desired ACH value depends on the specific space and its intended use. Different environments, such as residential areas, commercial buildings, or specialized facilities, have varying ACH recommendations to meet specific air quality standards.
Recommended Air Changes per Hour by Room Type
| Building/Room | Air Changes per Hour (ACH) |
|---|---|
| Residential | |
| Basements | 3-4 |
| Bedrooms | 5-6 |
| Bathrooms | 6-7 |
| Living rooms | 6-8 |
| Kitchens | 7-8 |
| Laundry room | 8-9 |
| Non-residential | |
| Offices | 6-8 |
| Business offices | 6-8 |
| Cafeterias | 7-12 |
| Conference rooms | 8-12 |
| Medical procedure offices | 9-10 |
| Copy rooms | 10-12 |
| Main computer rooms | 10-14 |
| Smoking area | 13-15 |
| Restaurants | |
| Dining area | 8-10 |
| Food staging | 10-12 |
| Kitchens | 14-60 |
| Bars | 15-20 |
| Public places | |
| Hallways | 3-5 |
| Waiting rooms | 4-8 |
| Banks | 4-8 |
| Hospital wards | 6-8 |
| Gyms | 6-10 |
| Malls and retail stores | 6-10 |
| Restrooms | 6-15 |
| Classrooms | 6-20 |
| Foyers | 8-10 |
| Houses of Worship | 8-12 |
| Theaters and auditoriums | 8-15 |
| Restrooms | 10-12 |
| Swimming pools | 10-15 |
| Hospital facilities | 10-20 |
| Auditoriums | 12-14 |
| Smoking rooms (Don't⚠️) | 15-20 |
Further reading:
Falke, R. "Use the Air Changes Calculation to Determine Room CFM." Contracting Business, 24 Mar. 2016. https://www.contractingbusiness.com/service/article/20868246/use-the-air-changes-calculation-to-determine-room-cfm.