Roof vents are an essential part of your home.

They extend the life of your roof by preventing condensation in the attic that can damage the ceiling above.

They also help regulate temperature and expel excess heat in warmer months.

In addition, roof venting is required by most building codes.

So you must do your homework and learn what you need to know about installing roof vents.

That will help you to maintain your roof and comply with local building codes.

Why Roof Ventilation Matters

Your roof is the most essential part of your home.

It protects you from the elements and provides the most basic shelter.

A roof is also one of the most expensive parts of your home to replace.

Roof ventilation is critical to maintaining your roof in its best condition.

Avoiding roof damage can mean avoiding costly repairs to other parts of your home.

A damaged roof can have a cascading effect.

What You Need to Know About Installing Roof Vents [infographic]

The Effects of Roof Damage on The Rest of Your Home

Damage to your roof can cause leaks that damage other parts of your home.

Ceilings, walls, and floors are susceptible to leaking roof damage.

Damage to a carpeted area can require expensive repairs, even replacing the entire carpet.

Moist ceilings, walls, and floors can also breed molds and fungi that require extensive professional cleanup.

A leak that is not attended to quickly can become a major disaster.

It may require opening up ceilings for days or weeks while a heavy-duty dehumidifier sucks the moisture out of the air and affected materials.

Roof damage can also result in small spaces in your roof that become entry points for pests.

Pests such as insects and rodents can cause significant damage to your home, requiring professional intervention and expensive cleanup.

Rodents can infest the spaces in the walls of your home.

Their nests are filled with excrement that carries numerous diseases that can affect humans.

Because nesting and fecal materials are easily airborne, rodent extermination and cleanup can be an expensive job best left to professionals.

Roof damage that is left unchecked can eventually require a complete roof replacement.

Roof replacement is one of the most expensive repairs you will have for your home.

A new roof can cost thousands of dollars, and insurance may only sometimes cover the total cost.

Avoiding roof damage and keeping your roof in good condition is the best way to save money, avoid injury, and protect your investment in your home.

How Much Ventilation Do You Need

Ventilation is vitally essential to the maintenance and longevity of your roof.

Without proper ventilation, a roof can sustain damage from moisture and condensation accumulating in the year’s colder months.

Knowing how much ventilation your roof requires is an important consideration.

Inadequate roof ventilation can result in roof damage.

Generally, there are not many adverse effects from too much ventilation.

However, too much airflow through your attic can affect your home’s temperature and have other undesirable effects.

So it is best to know precisely how much ventilation you need and then err on the side of more than less.

Calculating how much roof ventilation you need is relatively simple.

The main contributing factors are the slope of your roof and the size of your attic space.

The main goal in installing roof ventilation is to balance intake and exhaust.

Generally, you want to ensure that the two are about equal, but it is best to err on the side of too much information over too much exhaust.

Calculating Net Free Area

The number you are looking for when figuring ventilation is “net free area” (NFA). NFA is the open space for air to flow in and out of your attic area.

Different types of vents have different amounts of NFA per square foot or vent.

To calculate the amount of intake and exhaust NFA you need, first, determine the square footage of the floor of your attic.

If your attic floor has a moisture barrier, figure one square foot of NFA per 300 square feet of floor space.

The total resulting NFA should be split evenly between intake and exhaust.

So an attic that is 1200 square feet will require 4 square feet of NFA, 2 for information, and 2 for exhaust.

Calculate one square foot of NFA for every 150 square feet of attic floor space if your attic floor has no moisture barrier.

The division between intake and exhaust remains the same.

If your roof slope is steeper than a typical roof, greater than 6:12, you will need more NFA.

That is because the steeper slope means more total airspace in your attic.

If your roof pitch is 7:12 to 10:12, add 20% to the standard calculation of NFA. For roofs with a slope of 11:12 or more, add 30%.

Types of Intake

Installing Roof Vents

The most common type of intake is a soffit intake.

The soffit is the area underneath the part of your roof that overhangs the exterior of your home.

Either single or continuous soffit venting is available.

Your roofer can help determine the best soffit venting type for your roof.

Ensure you have adequate NFA, especially on the intake side. A common mistake is providing too little intake NFA, so airflow is restricted.

Soffit venting is a great way to go because of its many benefits.

It is usually tucked away where you don’t see it, preserving the look of your home.

Also, its location under the eaves of your house provides added protection. It can keep debris from clogging or blocking your intake vents.

Another type of intake is both an intake and an exhaust vent.

Gable end venting is a slotted metal or wooden piece of siding similar to a heating vent in your home.

It is installed on the exterior wall of your house near the roof, where it has access to the attic.

Gable end vents rely on wind to push the air into the vent, so they are best to use on the side of your home that faces the oncoming wind.

It is recommended that there is an average breeze of 5 mph or more to make this kind of vent work properly.

Exhaust Venting

There are several different types of exhaust venting.

Most exhaust venting relies on warm, moist air naturally flowing upwards.

Exhaust vents are placed higher than the intake vents.

This causes air to flow up and out of the exhaust vents, drawing air through the intake vents into the space left behind.

One common type of venting is ridge venting.

Ridge venting is installed along your home’s roof ride, taking full advantage of moist, warm air’s upward flow.

It is a long metal sheet bent to fit the ridge of your roof.

It is installed slightly raised from the top, creating an open slot along the underside of its length.

The ridge vent will look different from the rest of your roof, so your roofer may install shingles over the ridge vent to hide it from view.

Static vents come in several shapes and sizes, but all follow the same principle of airflow.

These vents usually protrude from the roof and have small openings that allow air to move up and out.

Gable end vents, as noted above, work well in areas with a steady breeze.

Another type of exhaust vent that uses the draft is a turbine vent.

This vent has non-motorized turbines that are turned by the current.

The spinning turbines draw air up and out of the attic.

A less common type of exhaust vent is the powered or motorized vent.

This vent works like a turbine vent, but a motor turns the turbines.

The engine can work according to a thermostat or moisture monitor.

Always Use a Reliable Roofer

When installing ventilation for your roof, you must know what you are doing.

That is because adequate ventilation must conform to your home’s needs and local building codes.

Poorly installed ventilation can severely damage your roof and your home.

The experts at Eagle Watch Roofing are experienced in the installation of roof venting.

They can inspect your roof, including your ventilation, and make necessary repairs.

This will keep your roof in its best condition for its life expectancy or even beyond.

Contact them today for a free estimate.


In conclusion, proper roof ventilation is crucial for maintaining the integrity of your roof & protecting your entire home.

It prevents condensation buildup, regulates temperature, and expels excess heat, contributing to the longevity of your roof.

By avoiding roof damage, you can prevent costly repairs to other parts of your home and protect your investment.

Understanding the requirements and guidelines for installing roof vents to comply with building codes and ensure optimal ventilation is essential.


How do roof vents extend the life of my roof?

Roof vents prevent condensation from accumulating in the attic, which can lead to moisture damage and premature deterioration of the roof structure.

Do building codes require roof vents?

Yes, most building codes typically require roof venting to ensure proper ventilation and prevent potential issues such as mold growth and excessive heat buildup.

Can roof damage affect other parts of my home?

Yes, a damaged roof can result in leaks that damage ceilings, walls, floors, and even carpets. It can also create entry points for pests, leading to further damage & potential health risks.

What are the risks of not addressing a leaking roof promptly?

Delaying repairs for a leaking roof can result in more extensive damage, including mold growth, structural deterioration, and costly repairs to other areas of your home.

How can roof ventilation help regulate the temperature in my home?

Proper roof ventilation allows hot air to escape from the attic, reducing heat buildup and creating a more comfortable living environment, especially during warmer months.

How often should roof vents be inspected?

Roof vents should be inspected regularly, at least once a year, to ensure they are in good working condition and free from blockages or damage.

Can I install roof vents myself, or should I hire a professional?

Hiring a professional roofer with experience in roof vent installation is recommended. They can assess your specific roof requirements, ensure proper installation, and comply with building codes.

What factors should I consider when determining the amount of roof ventilation needed?

Installing Roof Vents

Factors such as roof slope, attic size, climate, and local building codes play a role in determining the amount of ventilation required. Consulting with an expert can help determine the appropriate ventilation for your situation.

What are the different types of roof vents available?

Standard roof vents include ridge vents, static vents, soffit vents, gable end vents, and turbine vents. Each type has benefits and considerations, and the choice depends on your roof’s design and requirements.

How can I ensure proper maintenance of my roof vents?

Regular inspection and cleaning of roof vents are essential to ensure they remain free from debris and obstruction. Additionally, addressing any signs of damage or deterioration promptly will help maintain the effectiveness of your roof ventilation system.