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.
Whirlybird vs attic fan.
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.
With this said neither the turbine nor the ridge vent will act upon moisture.
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.
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.
In summer air movement helps rid the attic space of.
The sun does that.
It is a con to make people think the spinning action is like running a fan and mechanically drawing hot air out.
They make noise too.
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.
How much air must be moved.
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.
A solar fan is able to actively pull more air into your attic than a turbine can.
They re also quieter than whirlybirds and operate all year round.
Of vented area for every 300 sq.
The whirly bird or turbine vents are worse than useless.
It is hard to find this kind of data from the manufacturers of the wind driven fans but there seems to be a consensus when surveying the different solar powered roof ventilation fan options that they are equivalent to 10 to 30 whirlybirds.
Solar fans don t require any electricity wind or attic pressure to spin.
Without ventilation unfinished attic spaces can end up having stagnant air.
Roof vents vs whirly birds.
Full length ridge vent in combination with soffit vents is best.