Why Proper Attic Ventilation is Important – What You Should Know

july 20TH, 2020 UPDATED 2:00PM CT
Why Proper Attic Ventilation is Important - What You Should Know - San Antonio, TX - 02

When most people think about having a new roof installed, they think about the final product that they will see on the outside. Most people don’t consider what goes on inside of your home in the attic. But when it comes to roofing in San Antonio, your attic is important. More specifically, attic ventilation is important. Unfortunately, most homes don’t have adequate attic ventilation. But why is proper attic ventilation so important and what will happen if you don’t have it?

What is attic ventilation?

Before we dive into the reasons why attic ventilation is so important, why don’t we define what it is. In simple terms, ventilation is what keeps the air flowing through your attic. Without proper ventilation, air just sits stagnant. It’s ventilation that helps the air from outside pass through your attic, removing excess heat as it does so.

Why is attic ventilation important?

When it comes to roofing, the ventilation in your attic is extremely important. Why? Not only does proper ventilation help to keep the temperatures within your home more comfortable, but it can also help to prevent damage from occurring. Without proper ventilation in your attic your home is subject to moisture buildup. Once moisture starts to build up you can quickly run into other problems including bacterial buildup and mold growth, wood rot, popped shingles, and ice dams.

Attic Ventilation in the Summer Months

As we all know, heat rises. That’s one of the first things they teach you in any science class. But this isn’t always the case. Without proper ventilation in your attic, heat doesn’t actually rise – it migrates.

In the hot summer months when the sun is beating down on your roof, it heats up your attic. Without proper ventilation your attic will then heat up and the hot air will start to migrate. Where will it migrate to? Other areas in your home. As a result, your house will heat up very quickly. The hotter the day, the hotter your house will become.

Of course, the hotter our house becomes, the higher we turn up our AC. And as we’re sure you are well aware, the higher you turn up your AC, the higher your electrical bills will be.

But your heating bills aren’t the only thing you have to worry about without adequate ventilation in the summer months. When excess heat builds up in your attic it can lead to moisture buildup. In turn, this moisture can damage your roofing materials. Not only that, but along with moisture buildup also comes the buildup of mold and mildew.

In hot summer months, proper ventilation can help to prevent damage and keep your home cooler.

Attic Ventilation in the Winter Months

Summertime isn’t the only time that you need to think about proper attic ventilation. In the winter months you don’t have to worry about the sun heating up your attic – but that doesn’t mean you don’t have to worry about the heat. Remember that science class where you learned that heat rises? Well, it’s the winter months where this comes into play.

During the winter you will turn on your heat to keep your home warm. Your attic will be cool because there is no sun beating down on it. But – remember, heat rises. So all of the heat from your home is going to go where? You guessed it – straight into your attic. And along with this heat will come moisture buildup.

As the moisture builds up in your attic, it gets shocked by the cold air and condenses. This can lead to popping and buckling roof shingles or metal roofing. It can also cause your wood to rot and if that happens you will have to replace your entire roof. And of course, anywhere there is moisture buildup, there is also the risk of mold and mildew.

If you live in an area where there is snow, improper ventilation can also lead to the formation of ice dams. When the heat from the attic starts to melt the snow on the roof, the snow rolls off the roof and refreezes in the eaves and gutters. Eventually, as ice starts to build up, water will not be able to properly drain from the roof and water will start to collect under your roofing materials.

Proper ventilation can help to prevent this from happening.

How does attic ventilation work?

When it comes to roofing in San Antonio, ventilation works to create air flow. There are two primary methods used to help ventilate an attic: exhaust vents and intake vents.

Exhaust vents are vents that allow moist, warm air to flow out of the attic. They include ridge vents and turbine vents.

Intake vents are vents that allow air to flow into the attic. These include cable vents, under-eave vents, and rafter vents.

These are both natural forms of attic ventilation and are the most popular forms used by roofing companies.

But when it comes to roofing in San Antonio, natural forms of ventilation aren’t the only option. Attic ventilation fans are another alternative. These are a mechanical form of ventilation that use a fan to draw in cool air and force out hot air. The obvious downfall of mechanical ventilation is that it requires electricity to operate, thereby raising your electric bills.

What are the benefits of proper attic ventilation?

It extends the lifespan of your roof. Without proper ventilation, your roofing is subject to moisture buildup which can lead to a wide range of damages and repairs. Proper ventilation can help to prevent the buildup of mold and mildew, wood rot, shingle buckling, and more.

It cools the temperature in your home. When your attic is hot so is the rest of your home. By ensuring your attic is properly ventilated you can help to keep the rest of your home cooler too.

It reduces energy costs. By keeping the temperatures in your home cooler, proper attic ventilation can also help to reduce the amount that you need to spend on air conditioning in the summer months.

Common Myths about attic ventilation

When it comes to roofing in San Antonio, there are several myths circulating about attic ventilation:

More attic ventilation is always better

More attic ventilation doesn’t necessarily mean good ventilation. Rather, you want to find the right balance of air ventilation. Generally speaking you want 1 square foot of ventilation for every 300 square foot of ceiling space. With that being said, there are other factors that can influence this recommendation. Speak to a professional to learn more about adequate air ventilation.

The ventilation in the attic is causing heat loss in the winter

If you’re experiencing heat loss in the winter, it’s not because of your attic ventilation. It’s probably due to poor insulation.

Roof vents = roof ventilation

When it comes to roofing, there are some roof vents that don’t provide adequate ventilation. Ridge vents, for example, are the most cost effective vents that you can buy but with baffles they don’t provide any ventilation at all. Other types of vents pose different problems.

If you aren’t sure whether your roof vents are providing your attic with proper ventilation, speak to a San Antonio roofing contractor today. Proper attic ventilation is essential for keeping your home warm and for protecting the materials of your roofing so it’s something you will definitely want to discuss with a professional.

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McAllen Valley Roofing Co.

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5828 Sebastian Pl, Suite 102 San Antonio, TX 78249

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