I have a 1300 sq/ft house with 8 foot ceilings that recently had a metal roof put on.  They didn't exactly cut away wood where the ridge vent is even though they installed a ridge vent.  There is a 1.5x1.5 vent at 1 gable end and we have soffet vents.

My question is, how much attic ventillation do you need to run a whole house attic fan with a house  similar to mine.  Also, any web sites you recommend to review products such as this.