How to Choose the Right Ventilation Fan Power

How to Choose the Right Ventilation Fan Power

How to Choose the Right Ventilation Fan Power

When choosing an exhaust fan for your garage, basement, attic, or greenhouse, it’s important to consider not only the room size but also humidity levels, temperature, and air quality.
The key performance metric to focus on is CFM (Cubic Feet per Minute) — the volume of air a fan can move per minute.


What CFM Means and Why It Matters

CFM shows how efficiently the fan ventilates your space. A higher CFM means stronger airflow, but more is not always better.
An oversized fan may create unnecessary noise and energy waste, while an undersized one won’t provide proper ventilation.


How to Calculate the Required CFM

You can estimate the required fan capacity using a simple formula:

CFM = (Room Volume × Air Changes per Hour) / 60

Where:

  • Room Volume (ft³) = length × width × height

  • ACH (Air Changes per Hour) = how many times per hour the air in the room is completely replaced

Recommended ACH values:

  • Garage: 6–10

  • Basement: 8–12

  • Attic: 10–15

  • Greenhouse: 20–30

Example:
For a garage measuring 20 × 15 × 8 ft = 2400 ft³, and 8 air changes per hour:
CFM = (2400 × 8) / 60 = 320 CFM

So, you need a fan rated at least 320 CFM.


What Else to Consider

  1. Fan size (diameter) – larger fans can move more air with less noise.

  2. Noise level (dB) – especially important for living spaces like attics or basements.

  3. Energy efficiency – look for EC motors or smart control systems.

  4. Mounting type – wall, ceiling, or window, depending on your setup.

  5. Backdraft protection – prevents air, dust, or insects from entering back into the room.


Xcity Solutions for Every Need

Xcity offers a wide range of ventilation fans designed for different spaces and requirements — from compact models for small garages to high-performance fans for greenhouses or industrial use.
All models feature EC technology, smart temperature and humidity sensors, and optimized noise control, ensuring efficiency and comfort.


Xcity Ventilation Fan Specifications

Model Type Size (Inch) Power (W) Air Volume (m³/h) Speed (RPM) Noise (dB) Package Size (mm)
FANXEXHAUST10A EC type with smart controller, 2300mm USA plug, integrated Temp. & Humidity Sensor 10 18 1050 1650 <62 360×360×235
FANXEXHAUST12A EC type with smart controller, 2300mm USA plug, integrated Temp. & Humidity Sensor 12 40 1350 1650 <67 410×410×250
FANXEXHAUST14A EC type with smart controller, 2300mm USA plug, integrated Temp. & Humidity Sensor 14 45 2000 1600 <68 465×470×240
FANXEXHAUST16A EC type with smart controller, 2300mm USA plug, integrated Temp. & Humidity Sensor 16 70 2500 1600 <68 510×530×255
FANXEXHAUST20A EC type with smart controller, 2300mm USA plug, integrated Temp. & Humidity Sensor 20 75 4500 1200 <70 630×630×280
FANXEXHAUST24A EC type with smart controller, 2300mm USA plug, integrated Temp. & Humidity Sensor 24 85 5650 920 <70 775×775×290

Final Tip

If you’re unsure which model suits your needs, choose one with about 10–20% higher CFM than your calculation.
This will guarantee effective air circulation even if filters get dusty or humidity increases.


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