HomePerformance Venting Capacity

Solar Attic Fan Venting Capacity and Sizing Chart
How Many Solar Attic Fans Do I Need?

Several factors can affect the amount of attic ventilation a home needs. Variables such as vaulted ceilings, amount of existing venting (soffit, ridge, gable), attic shape, pitch and obstructions must all be taken into account when calculating the amount of attic venting needed. Your Natural Light dealer will determine the correct size unit or units needed for your specific installation. The output chart below reflects the average venting capacity and cfm output for each solar panel size available.

Natural Light Solar Attic Fan Output Chart
Solar Panel Size Venting Capacity CFM Output
16 Watt Model up to 1,300 sf up to 1,184 cfms
32 Watt Model up to 2,200 sf up to 1,560 cfms
48 Watt Model up to 2,825 sf up to 1,881 cfms
65 Watt Model up to 3,350 sf up to 2,105 cfms

CFM refers to cubic feet of air moved per minute. The higher the cfm number, the greater the capacity to move air. 

https://www.solaratticfan.com/wp-content/uploads/2018/07/mountain_home_with_attic_fan.jpg
https://www.solaratticfan.com/wp-content/uploads/2018/07/reduces_attic_temperature.gif
https://www.solaratticfan.com/wp-content/uploads/2018/07/black_attic_fan_on_cedar_shake_home.jpg

16-watt roof-mounted solar attic fan installed on a steep roof of a cedar shingle home.

Solar Attic Fan Residential Unit Estimator

The charts below should be used as a general guideline for how many Solar Attic Fans are needed for residential installations based on square footage and roof pitch.
Download Solar Attic Fan Estimator Sheet pdf.

https://www.solaratticfan.com/wp-content/uploads/2018/07/4-12-roof-pitch.gif
Attic Size Attic Fans Needed
800 sf (1) 16 watt
1,260 sf (1) 16 watt
1,600 sf (2) 16 watt OR
(1) 32 watt
2,100 sf (2) 16 watt OR
(1) 32 watt
2,400 sf (3) 16 watt OR
(2) 32 watt OR
(1) 48 watt
3,000 sf (2) 32 watt OR
(1) 65 watt
Attic Size Attic Fans Needed
800 sf (1) 16 watt
1,260 sf (2) 16 watt OR
(1) 32 watt
1,600 sf (2) 16 watt OR
(1) 32 watt
2,100 sf (3) 16 watt OR
(2) 32 watt OR
(1) 48 watt
2,400 sf (2) 32 watt OR
(1) 48 watt
3,000 sf (2) 32 watt OR
(1) 65 watt
https://www.solaratticfan.com/wp-content/uploads/2018/07/8-12-roof-pitch.gif
https://www.solaratticfan.com/wp-content/uploads/2018/07/12-12-roof-pitch.gif
Attic Size Attic Fans Needed
800 sf (2) 16 watt OR
(1) 32 watt
1,260 sf (2) 16 watt OR
(1) 32 watt
1,600 sf (3) 16 watt OR
(2) 32 watt OR
(1) 48 watt
2,100 sf (2) 32 watt OR
(1) 48 watt
2,400 sf (2) 48 watt OR
(1) 65 watt
3,000 sf (3) 32 watt OR
(2) 48 watt OR
(1) 65 watt
https://www.solaratticfan.com/wp-content/uploads/2018/07/saf-logo2.png
https://www.solaratticfan.com/wp-content/uploads/2018/05/nles-logo.png
NATURAL LIGHT SOLAR ATTIC FANS

Natural Light Solar Attic Fans reduce heat build-up in your attic and can minimize the load on your HVAC system. Available for all roof types, solar attic fans install easily with no electrical wiring or structural changes and blend seamlessly into your roof line.

© 2021 Natural Light Energy System