Radiant barrier stapled to underside of roof.
Power roof vents problems.
The research concluded that if a powered attic ventilator will be used there must be a good air barrier between the living space and the attic.
These are real problems from real houses that have really happened.
Power attic ventilators can cause problems even without air conditioning.
If you use the older style of roof vent to provide air circulation then you must install traps or blockage points that prevent them from nesting in your attic s insulation.
This protection feature reduces the amount of air that moves which defeats the purpose of the older designs in the first place.
After that a different level of thinking is required.
Another would be backdrafting a water heater and putting carbon monoxide in the house.
One potential problem would be sucking moist moldy air up from the crawl space intothe house.
Roof vents create an additional roof penetration essentially another place of vulnerability where leaks can occur.
There is no risk of problems such a rust and bearing wear an tear as well when comparing it to other motorized ventilation alternatives.
Problems and solutions mixed exhaust vents.
Insufficient ventilation can lead to moisture problems during the winter and decreased energy efficiency during the summer but too much ventilation can be just as bad if not worse.
I blogged about this earlier.
Because solar attic fans operate with a lower power output they are unable to move as much air as some of the other options that are available.
By keeping your attic or roof cool and dry you will use less energy within your house to try and maintain a comfortable home without using external air conditioning equipment.
Roof vents and power roof vents are made to work in conjunction with vented soffits so that outside air will replace superheated attic air during hot summer days.
Power vents shouldn t be used because they create more problems than they fix.
I would look at a lot of problems and instantly point to insufficient roof ventilation as the cause and recommend more roof.
In researching the topic of attic ventilation in the past i figured out the building code rules worked well for roof pitches up to 6 12.
I used to think roof ventilation was the cure all for everything.
On paper the high vents are.
That means you will need to double up your investment in this area.