Attic Fans Vs. Passive Ventilation

Which is better, an electric, or solar powered fan, or ridge vent, combined with intake ventilation at the bottom of the slope (passive ventilation)?

The good news is that they both work!

My feeling is that this can be looked at in two ways, first from an existing roof standpoint, then from a standpoint of re-roofing.

Probably, if the existing roof is staying, I would recommend attic fans, either electric or solar powered. They are normally controlled by a thermostat, and engage when the attic temperature reaches a pre-set level. Installing fans to an existing roof is easy, economical, and if installed professionally, cannot cause a roof leak.

In the case of a re-roof, my belief is that passive ventilation, ridge vent, along with intake at the bottom is better, simply because there is an opportunity to properly install both, while the roof is open. The passive type creates a “river of air”, entering from the bottom of the slope, then exiting through the ridge, continually moving passively, continually drying and cooling. Additionally, because this type is indeed passive, it can never break down or need repair, a problem to which the fan type of ventilation is subject.

Of course, the main thing is to properly ventilate. Your licensed roofing contractor, (hopefully Raneri and Long), can provide proper guidance and assist you in the right choice to best suit your needs.

Raneri and Long, the roofing name you can trust!