Proper ventilation at the roof is important to a complete attic ventilation system as well as to the structural integrity of the roof. There are two basic categories of roof vents including passive and powered. A roofing contractor can install four different kinds of roof vents that all fall into one of the two categories.
All roof vents work by allowing outside air that enters the attic through the soffits to escape out the top of the roof, creating attic ventilation that carries away moisture and condensation before it has any chance to damage the structure of the roof, the insulation or the home. In wintertime, without proper ventilation, ice dams can occur.
Below are the four different types of roof vents along with some pros and cons. Your roofing contractor can help you decide which type of vent will work best for your roof and why installing the proper roof vent system can impact the structural integrity of your home over time.
Passive Roof Vents
Low Profile Roof Vents
|Low-Profile or Louvered Roof Vent|
The most common type of roof vent is probably the low profile roof vent. Also referred to as “louvered vents” these vents have a low profile and feature a slant-back design to guard against weather infiltration especially in steep-slope applications. They are often available in either aluminum or galvanized steel and can provide between 50 and 60 square inches of net free area (NFA) per vent. Installation is relatively easy as most include pre-drilled holes for nailing.
Multiple low profile roof vents must be installed on the roof according to the square foot size of the attic. Under 1,000 square feet of attic space requires only 4 vents while a 3000 square foot attic can require as many as 12.
The low profile vent is usually installed on the back roof to minimize any unsightly appearance they may cause. The color of the vent can often be matched to the color of the roof depending on the manufacturer that is chosen.