Re: Cooling down / removing attc heat
you mentioned gables but not eaves. Does your home have eaves? That is the part that extends beyond the roofline at the top of the walls and is usually where the gutters are located.
I have always found a concensus that ridge vents are the best static vent system for an attic. The power attic ventilators are fine (usually thermostatically controlled) but as with any other appliance, need to be maintained. Also, in order to maximize whatever you do, you need to bring fresh air in as low as possible and then exhaust it high. With gable vents anything you do will only draw air in right along the ridge of the roof.
I would much rather see the ridge vents (which you apparently already have) used in conjunction with the eave or soffit vents. The natural thermal velocity of the air will create a path of fresh air coming in and out from the lowest point to the highest point.
All the best, Irishmist
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