When it comes to things with the home, attic ventilation is one that is often misunderstood. Essentially, ventilation is just about circulating the air within the attic to ensure it remains fresh and keep moisture levels to a minimum. Roughly 90 percent of U.S. homes have moisture levels that are unreasonable. By becoming familiar with the fact that your home can gain an advantage from attic ventilation may not just be a life-saver but also a roof-saver. Here are a few of the misconceptions, along with the actual facts, that you should be aware of regarding attic ventilation.
Myth #1: More Attic Ventilation Is Better
Just like it is important to properly size your HVAC unit for your home, you also want to get the proper amount of ventilation for your attic. Failing to get the sufficient amount of ventilation can result in moisture problems throughout the winter and decreased energy efficiency throughout the summer. However, an excess amount of ventilation can often be just as bad—sometimes even worse. The roof vents allow for additional penetration, which is ultimately another area where leaks may occur. While some vents are indeed necessary, you don’t want to increase the number of penetrations in the roof needlessly. The seems can result in blowouts during a hurricane or allow wildfire sparks to enter into the home and catch fire.
So, it comes down to this: how much ventilation do you need? The best thing you can do is speak with a professional to find out exactly what your home requires. As a rule of thumb, though, you will need a ratio of 1:300, which means that you require one square foot of ventilation for each 300 square foot of ceiling space. With that being said, air interference and resistance will reduce the overall area of true ventilation, which means that entire venting openings will not count as vented space.
Myth #2: Roof Vents Are Only Needed for Warmer Climates
There are a lot of individuals who assume that the importance behind roof ventilation is to boost energy efficient throughout the summertime. Proper ventilation can indeed do this, but the color of the shingles, exposure to the sun, and insulation are ultimately more important to the overall energy efficiency than the actual ventilation. Hot air can be reduced in an older home by installing roof vents, but there are more cost-effective and low-risk ways to boost your home’s energy efficiency.
In the meantime, you should focus on preventing moisture damage, as there is greater benefit and it applies more to colder climates than warmer climates. Actually, the colder the climate, the more likely the home will reap benefits from ventilation. To have an unvented roofing system installed in a colder climate, a rigid and highly rated insulation will be needed to help prevent condensation on the roof sheathing. For warmer climates, this won’t be necessary since condensation isn’t a problem. Think about of frequently dew forms on the grass where you live. In these types of climates, warm attic spaces are eliminated with the installation of a thermal barrier along the home’s roof line as opposed to the floor of the attic.
Myth #3: Roof Vents Have the Capability of Removing Warm Air Throughout the Winter
Many individuals assume that due to the fact that heat rises that ventilating an attic throughout the wintertime means that warm air is being released and a drag is being created on the heating efficiency of the home. Now, if this is indeed true, then you have much larger problems on your hands than allowing warm air to leave your home. Inadequate insulation tends to be the problem, even though you can go into the attic on a sunny, winter day and the space be warmed by the sun more than the home’s furnace.
Unless the roofing system is equipped with insulation on the deck and is designed with no ventilation, the furnace shouldn’t be providing heat for the attic space. Even worse, poor insulation is sure to be allowing moisture-laden air into the space. When this moist, warm air meets the roof, condensation is likely to form, leading to more deterioration of the insulation or rotting of the wood. If you believe this may be an issue, wait until the sun sets and measure the attic’s temperature. This temperature should be in close range to the temperature outside.
Myth #4: Research Studies
There have been a significant number of studies that have been performed about the optimization and effectiveness of general roof ventilation and certain kinds of roof vents. When it comes to the benefits of roof ventilation, they’re undisputed. Lab settings are poor indicators of real world weather and wind behaviors. In addition, regional differences can amplify specific traits of ventilation over a period of time. While one thing may work in Seattle, WA, the same thing may not work here in Huntsville, AL.
In many ways, ventilation of the roof is just as much of an art as it is a science. When it comes to roof installation and performing the installation based on what you have read online, it is similar to attempting to diagnose the skin rash that came up on your leg using WebMD. Locating an experienced, reputable roofing contractor who has been working in your region for years is better than any online research or “expert”.
Myth #5: Having Roof Vents Is the Same as Having Roof Ventilation
Though not many people agree on the best ventilation system for roofs, everybody tends to agree that some vents hardly do any good at all. For instance, ridge vents are by far the most cost-effective and effective vents available. When a baffle isn’t present, a ridge vent may create zero ventilation. Gable vents often circulate air through a nominal percentage of the attic. Static vents, along the roof line, are good for ventilation, though they are not recommended because of leak issues. Soffit vents can leave air trapped at the top of the attic. The most effective system is a ridge-and-soffit ventilation system, but these tend to vary from one roof to the next.
If you are unsure how the vents work on your roof or uncertain about the ventilation in general in regard to your roof, get in touch with us at C and K Roofing today. This risk and reward for having inadequate or no ventilation, on top of the relatively affordable installation cost of a properly working ventilation system, makes it among the most unforgivable sins when it comes to residential property maintenance negligence.