Attic and Roof Ventilation

One of the most important but little-known aspects of proper roofing installation is adequate ventilation. There are numerous reasons why ventilation is essential when it comes to roofing. Things like the growth of mold, heating and cooling costs, and even the life of your roof are all impacted by ventilation. When determining how much ventilation to install, the general rule of thumb most contractors abide by is 1 square foot of ventilation per 300 square feet of attic floor space.

Attic and Roof Ventilation

What type should I have?

Without seeing your home’s roof it is hard to say what type of venting you could benefit the most from. There are many venting options and they all work exceptionally well in certain situations while providing little benefit in others.

One thing to note is that the trend currently is to provide more ventilation (in the right spots) than in older homes. Building codes have changed such that more insulation between the living space and the attic is required and more ventilation in the attic space is required.

Exhaust Vents

This type of ventilation allows air to flow out of your attic and keeps unwanted temperatures from building up below the roof deck. Generally, there are three types of exhaust vents used in roofing.

Gable vents, or wall louvers, are located in the gable ends of the attic and can be used in combination with other vents.

Gable vent

Ridge vents run along the peak of your roof. They include a cover (baffle) to protect rain and snow from coming right into your attic.

Wind turbines are mushroom-shaped caps atop roofs designed to catch natural wind currents, which spins an internal fan and propels hot air out of the attic. Wind turbines are most effective in areas where winds average about 5 mph.

Turbine vent

Intake Vents

Exhausting air is only part of the ventilation equation. You also need intake vents, which help to keep the air flowing through the exhaust vents. Without an intake, the exhaust vents cannot fully serve their purpose. There are generally two types of exhaust vents used in roofing.

Box vent

Static vents have no moving parts. These can be box vents, dormer, roof louver and many others. At their core, they are protected holes in the roof decking.

Soffit vents provide a breath of fresh air.  Made of aluminum or vinyl, they contain tiny perforations or slits for airflow. Soffit vents are most effective when used in combination with a ridge vent.

Soffit vent

Ventilation Maintenance

You or a professional roofing contractor should inspect your roof vents once per year to ensure that no blockages have occurred and your roof is ventilating properly.

  • Periodically remove screens of dust, dirt, spider webs, leaves and other bits of nature that restricts the flow of air
  • Fix rips or tears on any screens or flashing
  • Looks for rust or rot around the flashing
  • Move insulation away from soffit vent openings

If you notice ice damming, mold or moisture in your attic, have a roofing professional review if you have enough ventilation.

If you would like more information on roof venting and to discover if your current roof has enough ventilation, contact the roofing experts at Pro Home Improvement at 888-776-1998 or schedule a roof estimate to get the best insights and assistance for your roof and ventilation needs.

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