Of course there should be intake vents to ensure a balanced system.
How many roof vents required.
Ventsure 4 foot strip heat moisture ridge vent.
Now you know how many square inches of attic roof venting you need for the roof and soffit.
Advantages of proper roofing ventilation.
Federal housing authority recommends a minimum of at least 1 square foot of attic ventilation evenly split between intake and exhaust for every 300 square feet of attic floor space.
And in many of these cases the hip roof forms a large volumetric attic space to ventilate.
Feet of attic space divided 50 50.
Figure 7 mechanical ventilation used with a hip roof.
Proper attic ventilation consists of a balance between air intake at your eaves soffits or fascias and air exhaust at or near your roof ridge.
For the number of soffit vents in the example divide 8 square feet of ventilation needed by 0 5 for the number of rectangular vents required 16 in the example.
Taking advantage of this natural process referred to as passive ventilation is the most common way to vent an attic.
Luckily there is a basic formula you can use to determine this.
In our case the required 4 vents for the 1200 sq ft house multiply the 144 cubic inches by 4 576 cubic inches.
The size of your roof and attic space will determine how many roof vents you need.
Next divide that number by 2.
Foot of ventilation for every 150 sq.
For the 1 150 attic ventilation requirement simply double the amount of exhaust and intake calculated.
27 lineal feet required.
Proper attic ventilation offers numerous advantages to the homeowner.
A roof vent is a type of fixture installed on your roof that exhausts hot air.
Of net free area of exhaust needed at or near the ridge.
One method is to use a powered attic vent with a humidistat thermostat located close to the ridge or top of the roof.
Of net free area of intake needed at or near the soffit.
Ridge static attic vents 384 00 minimum sq.
Choose one of the following products to meet the recommended exhaust nfva of 528 square inches.
This calculator gives you the required attic ventilation requirement.
Although there are many different types of roof vents to choose from ensuring you have the right number of both intake and exhaust vents is a central part of roof design.
