Allowing fresh air through your attic might seem contradictory knowing that your home requires insulation to minimize changes in temperatures and achieve monthly energy savings. The concept behind the roof and attic ventilation, however, is a sensible one. When an attic traps heat and moisture, it could spell trouble for your roof and its numerous components. Making sure this part of your home that “breathes” can help save yourself from the stress and hassle of untimely and costly repairs.
In this blog, local residential roofing company CQ Construction & Roofing highlights the importance of ventilating your roof and attic, as well as the components that make up this facet of the roofing system.
Understanding Roof and Attic Ventilation
To better understand roof and attic ventilation, you have to know the consequences of not having one in the first place. Remember that they serve two vital functions: draw cool, fresh air into the attic and let hot, moist air escape out of the roof. An improperly ventilated roof can contribute to heat and moisture buildup inside the attic, leading to issues that will compromise the roof’s weather performance and your home’s indoor comfort.
- Heat Buildup in the Attic
During the hot summer months, the sun’s heat beating down on the roof’s surface results in increased attic temperatures. It radiates through the attic floor and into your home, warming up your indoor spaces. As you rely on fans and your air conditioner to combat excessive indoor heat, these units will have to work harder to perform and provide comfort. Expect an increase in your home’s energy consumption, which will reflect on your monthly utility bills, as well as inefficiently running HVAC systems.
Another issue caused by too much heat inside the attic involves your home’s roof and interior components. Signs of warping may appear on the wood framing of your attic and, later on, on your wall and door frames as the heat moves down from the attic floor to your indoor spaces. Blisters may appear on paint and wallpaper, as well. What you need to watch out for, however, is the roof itself. Too much heat can shorten the lifespan of your roof shingles, leading to visible damage and loss of protective granules on the roof surface.
- Moisture Buildup in the Attic
Summer is not just the only time issues related to improper roof and attic ventilation arise. During the colder months, water vapor generated from normal household activities tends to fill the indoors. Moisture will then collect inside the attic, especially on the roof’s underside, condensing and wetting the insulation. This affects your home’s energy efficiency because of the diminished R-value of the attic insulation. Not only that, but it also paves the way for the growth and spread of mold, as well as the presence of rot on your roof’s rafters and other wooden components.
In areas where temperatures drop significantly in the winter, the lack of ventilation on your roof and attic can be a factor in the formation of ice dams. Too much warmth inside the attic causes snow and ice to melt and flow toward the gutters and eaves where it will freeze again. Subsequently, the water will back up under the shingles and down the roof’s decking, resulting in mold and rot.
Having your roof and attic properly ventilated is indeed your first step to making sure your home remains stable and comfortable. If you are looking to tackle an asphalt shingle or metal roof replacement project, you must consider the components that will make up your roof’s ventilation system.
Components of a Balanced Roof Ventilation System
Roof and attic ventilation works on the concept of rising hot air, utilizing three important components which are as follows:
- Intake Vents
These vents are responsible for drawing cool, fresh air toward the roof and into the attic. The most common is the soffit vents installed directly underneath the roof’s eaves. They can be individual vents spaced every few feet or as one continuous soffit with perforations that extend from one end of the eave to the other. These provide better airflow in the warmer months and moisture protection in the colder months.
- Exhaust vents
As cooler and denser air enters the soffit vents, hot air begins to rise and escape the roof through exhaust vents. The most common is the ridge vents installed on the part of the roof where two slopes meet. During new roof construction, the pros leave the gap in the sheathing along the ridge before covering it with perforated vents. These are then covered by specialty ridge shingles to ensure the roof’s uniform appearance.
- Attic Insulation
Whether you plan to install asphalt shingles or metal panels for your roofing system, your attic should have enough insulation to ensure consistent indoor comfort and long-term roof health and performance. Adding insulation doesn’t come cheap for the most part, but it can help reduce the amount you spend to keep your living spaces comfortable by up to 30%.
Considerations for Roof and Attic Ventilation
According to roofing industry experts, the recommended amount of ventilation is about a square foot per 300 square feet of attic area. Even when there’s no wind, intake and exhaust vents take advantage of natural convection to ensure continuous airflow from the roof’s underside to the roof’s peak.
As for the insulation, you have to take a closer look at its thermal resistance rating or R-value before you install it inside your attic. The higher the R-value, the greater it is at insulating the whole space effectively. This, however, will be dependent on the type of insulation, its thickness, and density. According to ENERGY STAR®, the recommended level for most attics is an R-38 type of insulation or about 10 to 14 inches of insulation.
CQ Construction & Roofing offers a full range of residential and commercial roofing services, including new construction, repairs, replacement, and maintenance. We provide quality installation and honest pricing on roofing projects of all sizes. Call (850) 683-4169 or fill out our contact form to request a free estimate. We serve homeowners in Crestview, FL, and many nearby communities.