A turbine has a series of vanes that spin as wind passes through them.
How many turbines do i need on my roof.
There are also gable and roof fans which actively pull the hot air out of the attic.
In addition pay attention to the maximum roof pitch that will work with the turbines.
The turbines are adjustable so that the spinning part is level even though the roof is slanted.
Having the correct number of turbine vents will provide an effective and balanced system.
Thus if your attic is 450 square feet you need roof vents equaling 3 square feet.
These will not rust.
The first step in determining how many vents you need is to calculate the net free area nfa required.
Most codes use the 1 300 rule for minimum residential attic ventilation recommendations.
Unlike turbines this venting style does not have any moving parts.
If you decide to add more turbine vents to your roof be sure to buy ones that are aluminum.
As a general rule your roof needs 1 square foot of vent area for every 150 square feet of attic space.
A turbine is installed directly on the top of a roof and uses wind power to suck hot and humid air out of the attic.
How many turbine vents you will need depends on a number of factors including the size and type of building.
This means that for every 300 square feet of enclosed attic space 1 square foot of ventilation is required with half at the upper portion exhaust.
Not all turbines will fit all roof pitches.
Using a roof turbine ventilator to increase the flow of air in your attic is a great idea.
There s no point in wasting time and money getting the wrong ventilator for your roof though.