One potential problem would be sucking moist moldy air up from the crawl space intothe house.
Power roof vents problems.
According to the article powered attic fans can create excess moisture structural problems and combustion safety in a home.
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.
This protection feature reduces the amount of air that moves which defeats the purpose of the older designs in the first place.
For proper ventilation both high and low vents should be installed.
I used to think roof ventilation was the cure all for everything.
Of course you try to make the attic scuttle hole use air tight trim on your ceiling cans but it would be foolish to ignore the benefits of a reasonably powered attic fan working in connection with adequate soffit venting.
Power attic ventilators can cause problems even without air conditioning.
I blogged about this earlier.
Problems and solutions mixed exhaust vents.
Radiant barrier stapled to underside of roof.
I would look at a lot of problems and instantly point to insufficient roof ventilation as the cause and recommend more roof.
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.
On paper the high vents are.
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.
That means you will need to double up your investment in this area.
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.
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.
Another would be backdrafting a water heater and putting carbon monoxide in the house.
There is no risk of problems such a rust and bearing wear an tear as well when comparing it to other motorized ventilation alternatives.
Power vents shouldn t be used because they create more problems than they fix.
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.
Roof vents create an additional roof penetration essentially another place of vulnerability where leaks can occur.