Types of Roof Vents and Why They’re Important

Regardless of what type of roofing system your home has, it needs roof vents. A roof without vents will eventually run into problems and you’ll be left to decide whether to keep getting  roof repair or a replacement.

Why Does a Roof Need Vents?

Roof vents come in different shapes and sizes, but they all have one specific and major function: to prevent the attic from overheating. 

On a hot day, the outdoor temperature will affect the temperature in your attic. You want that attic temperature to be at least level with the outdoor heat. The problem is that the attic traps heat so that the roof becomes hotter than its surroundings. When this happens, issues start to develop.

The shingles are exposed to the heat of the sun, so if they are also being pummeled by heat from underneath — which is what happens when the attic is superheating — they receive double the punishment. The heat from the attic bakes the shingles, making them brittle and more prone to damage. It also affects the sheathing and other components of the roof, causing them to warp and to lose adhesion and integrity. Pretty soon, you’ll need a roof replacement.

In the winter, while it’s snowing outside, the trapped heat in the attic remains. When the snow collects on your roof, the snow at the top melts faster because that’s the hottest part of the roof (because heat rises). Snowmelt flows down to the colder bottom part of the roof, where it refreezes, forming ice dams at the edges of the roof and in the gutters. As more snow melts at the top, it becomes trapped by ice dams. There is no way for the water to escape, so it begins to back up. This is bad news for your shingles because water backing up means it’s finding its way through the shingles. Leaks will begin to form and you’ll need a roof repair.

Humidity is also a problem when the attic is superheating. During winter, when your home is artificially heated, humidity builds up in your hot attic. As there is nowhere for the humidity to go, it comes into contact with the attic’s surfaces and forms condensation. This moisture will find its way everywhere in the attic, causing all sorts of problems, from rot to rusting to mold growth. 

Water is also bad for your attic insulation as it causes the insulation to clump, rendering it useless. If all the insulation clumps, your home has absolutely no protection from the attic heat.

When your attic lacks ventilation, it also affects the living areas below it. Your HVAC system has to work overtime to achieve the temperature you need to be comfortable. If your HVAC is old, undersized, or needs servicing, it might not be able to achieve your desired cooling at all. This overworking can also shorten your HVAC unit’s life. You’ll be paying more for the extra energy it uses, and then even more when you have to replace it as soon as it breaks down.

That’s a lot of costs: roof replacement, HVAC replacement, high electricity bills, damaged insulation, medical bills if mold infestation causes sickness in your household, mold remediation, rotted drywall and possibly more.

Types of Vents

Here are the different types of vents. Talk to your contractor about the vents your home needs.

• Ridge Vents. The ridge or peak of the roof is where ridge vents are installed. They allow heat to escape at the top of the roof. They work with intake vents which push the hot air out and let the cool air in.
• Soffit Vents. These are the intake vents that help ridge vents do their job. Soffits are the underside of the roof edges. If there is a moisture problem in the roof, these are the solution
• Cupola Vents. These decorative features can help ridge vents. They function as intake vents.
• Powered Vents. When static vents are not enough, your roof needs powered vents. They are more effective at providing ventilation to the attic than their static counterparts. Powered vents are a better option for larger attics than static vents, as well. In Central Oregon, Master Flow power attic vents and solar fans are a great choice.
• Gable Intake Vents. Found at the gables, if you have soffit vents or ridge vents these vents may interfere with the flow of air and should be covered in this instance. In the absence of soffit vents these vents are useful for air intake.

Installation

It’s a good idea to talk to your attic insulation contractors about the type of vents that are best for your home. There are different factors to consider when choosing vents, so DIY may not be your best option. If you’re replacing a roof or building a new home anyway, the installation of vents falls within the purview of your contractor.

When installing roof vents, professionals have to consider the slope or pitch of your roof, the presence of penetrations, the average amount of rainfall in your area, the type of vents, the size of your roof, its aesthetics and other factors to make sure the attic receives enough ventilation as well as insulation while also not getting in the way of how the roof looks. Heat, humidity and water penetration are all important considerations.

While you might be able to install vents on your own, that doesn’t mean you should. With all these factors in play, it’s easy for a DIY enthusiast to make mistakes, from the choice of vent type to the placement on the roof. One mistake might lead to a re-do, which can double the cost of installation. You might also get something wrong so there is uneven or inadequate ventilation, which will not prevent your attic from superheating. Moisture and animal penetration are also serious problems if you end up installing vents that are too big. You might have to call a professional to correct your mistakes.

Need a professional insulation contractor with plenty of experience in installing the correct attic vents? Get in touch with us at Deschutes Roofing & Insulation. We also specialize in repairing and replacing roofs. Call us in Bend: (541) 241-5720, Portland: (503) 967-9590, Eugene: (541) 246-6860, Lake Oswego: (503) 468-7663, or Beaverton: (503) 928-8750. You can also use this form to contact us for a free estimate.