Whirlybird Vs Attic Fan

Full length ridge vent in combination with soffit vents is best.

Whirlybird vs attic fan.

A largely arbitrary rule of thumb that s been adopted into most building codes calls for 1 sq. Roof vents vs whirly birds. The sun does that. A solar fan is able to actively pull more air into your attic than a turbine can.

A solar fan doesn t rely on the wind and it actually has a more powerful motor in it so it keeps the temperature of your attic regulated regardless of wind conditions. Solar fans don t require any electricity wind or attic pressure to spin. Without ventilation unfinished attic spaces can end up having stagnant air. Without any air movement temperatures in the attic soar in summer and plunge in winter.

Also since the fan is powered by the sun it should turn off when the sky is overcast during a storm which will keep it from drawing rain into the attic. Although they don t work at night due to the lack of sunlight this is typically a non issue because they re most needed during the day when the sunrays are heating up your roof and attic. All things being equal wind driven turbine vents also known as a whirlybird roof vent do move more air than flat vents but only when the wind blows. In summer air movement helps rid the attic space of.

With this said neither the turbine nor the ridge vent will act upon moisture. It is a con to make people think the spinning action is like running a fan and mechanically drawing hot air out. Of vented area for every 300 sq. When considering ventilation for your attic it is very important to take into account moisture as well as heat as mold growing inside your attic is much worse than mold growing on the roof shingle surface on the outside.

Air movement in the attic helps prevent moisture buildup on rafters and on the bottom of roofing materials. The average domestic whirlybird moves around 100 cbm h at around 12 km h wind speed. Since your solar vent fan only moves 500 cfm a third to half that of a typical hardwired attic vent fan it probably won t move enough air to reverse the action of the ridge vent. They re also quieter than whirlybirds and operate all year round.

How much air must be moved.