How to Cool an Attic for Better Energy Efficiency: A Helpful Guide

When the warm weather comes, homeowners need a way to keep their air-conditioning costs low while maintaining a comfortable temperature in their living area. Turning down the thermostat, shutting the doors, and sealing the windows will only go so far, especially when hot air enters your home through your attic.

There’s no way around it; the typical attic is a major energy-suck, especially during the hotter months. That’s why we’re investigating how to keep an attic cool in the summer.

We’ll explore several tips, tricks, and home improvements to beat the heat. Read on to learn about the purpose of insulation and the importance of ventilation, attic fans, and more. With the right information and proper insulation installation, keeping your attic cool is no sweat.

Air Sealing

Ready to renovate? No, we’re not talking about knocking down walls.

Attic sealing involves plugging holes, filling gaps, and blocking air from entering your attic. Air leaks can be hard to spot, but if your house is losing cool air at record speed, it’s likely escaping from the attic. For many homeowners, answering the question “how to cool, keep attic cool, and save on energy” begins with sealing.

Whether you take on the project yourself or hire a professional team to seal your attic, you can expect the following benefits:

Consistent temperatures – Does your living room feel like an icebox while your bedroom remains hot and humid? One common cause of inconsistent temperatures and major temperature fluctuations is an unsealed attic. Depending on the location of your leaks, some rooms may be especially drafty and open to more heat exposure.
Less dust – Dust and dirt particles can enter your house through various gaps in your attic. Once inside, they can irritate allergies and lead to a never-ending mess. Attic sealing may help reduce all those floating bits of dust that you just can’t seem to get rid of.

Most importantly, like every tip on our list, attic sealing can increase home efficiency and lead to a lower monthly utility bill, and a more comfortable space to live in.

Attic Insulation

87% of homes throughout the US use air conditioning.¹ That means a lot of cold air is blowing. The problem is, if your attic lacks adequate insulation, that cold air is likely blowing straight out of your roof.

Attic insulation can help you retain your cool air during the summer months by creating a stronger barrier between the exterior and interior of your home. Today, there are several different types of attic insulation for homeowners to choose from, though some may be more effective than others depending on your specific situation.

Consider the following options for insulating your attic:

Fiberglass batt – These pinkish fiberglass fibers come in rolled-up sheets and can be custom installed into attics for high-quality thermal retention. Professionals prefer this style of insulation, and it offers a consistent return on investment for homeowners. Batt installation results in minimal dust and mess and can even help reduce street noise. For many homes, it’s the ideal choice for maximum energy efficiency.
Blown-in fiberglass – This loose-fill form of fiberglass is blown into your attic space to fill various cracks, crevices, and larger open spaces. Areas around pipes and wires may benefit from blown-in fiberglass, and the cost of this form of insulation is relatively low. This insulation may be best for irregular spaces or for filling out already insulated areas.
Blown-in cellulose – Made from shredded newspapers, cellulose can be an appealing choice for homeowners looking for an inexpensive answer to their insulation needs. Unfortunately, cellulose is vulnerable to moisture, causing mold and mildew. Additionally, manufacturers and marketers have made inaccurate claims about the pest control benefits of cellulose and boric acid. Be wary of misinformation regarding this form of insulation.
Spray foam – Airtight and long-lasting, this can be a viable insulation solution that may last several decades. This hard, moisture-resistant insulation can be sprayed directly into the roofline and can even strengthen your home’s structure. Be aware spray foam is a top-of-the-line material that commands a hefty price.

Attic Ventilation

Consider using physics to your advantage. As hot air rises, proper attic ventilation can assist in air circulation and overall cooling.

Give hot attic air somewhere to go by investigating the following attic vent options:

Static vents – A simple and inexpensive venting solution, static vents come in a variety of designs, including roofline, dormer, or eyebrow vents. With no moving parts—hence their name—these vents need to be properly installed, or they will result in unintended leaks.
Ridge vents – Installed at the peak of your roof and outfitted to remain mostly invisible to the naked eye, a ridge vent offers a subtle way to let out superheated air from your attic. A ridge vent is designed to prevent unwanted materials from entering your attic space with an internal baffle.
Gable vents – Typically, two gable vents are installed on the opposite ends of your attic walls. When air is following against your home, cool air will come through one vent while the other vent will act as an exhaust for hot air.

Remember, attic vents require upkeep. Clean them regularly to prevent various debris like leaves and dirt from interrupting the airflow, and repairs may be necessary if they’re damaged by inclement weather. You may need to replace older vents altogether because of rust or rot.

Attic Fans

Before air conditioning became ubiquitous in the US, a house fan was the main option for staying cool. Today, there are more efficient solutions than the traditional house fan. Attic fans are implemented alongside air conditioning systems to maximize air circulation and cooling potential.

Explore the following attic fan options to increase your home’s overall cooling efficiency:

Gable fans – If your attic already has a ventilated gable, adding a powered fan could be a relatively simple process to increase airflow. These fans can help speed up the process of exhausting hot attic air while providing cooling benefits almost immediately.
Roof fans – These fans require a thorough installation job to work properly. Roof fans are designed to hold up in harsh weather and provide a large ventilation output directly on top of your home.
Window fans – Avoid complicated installation by placing a fan in your attic window. Air sealing an attic and insulation may increase the efficiency of these fans and prevent unintended leaks.

While attic fans use electricity, their costs are significantly lower than standard air conditioning units. Additionally, solar-powered attic fans offer homeowners an environmentally friendly way to cool their attic that could offset overall energy costs.

Reflective Insulation

If you’re wondering how to cool an attic, one of the most effective ways is to stop heat from getting in, to begin with. Reflective insulation is designed to block radiating heat from the sun and, like a mirror, reflects light.

Curious about how reflective insulation can benefit your attic? Consider how reflective insulation works:

Radiant energy – As the sun beats down on your roof, the radiant energy heats the surface materials. That heat energy moves from the roof into the attic, heating the air, floor, ducts, and all other surfaces and objects.
Reducing heat transfer – Reflective insulation creates a barrier between the radiant heat from the roof and the rest of your attic. Adhered to the interior walls of your attic, this form of insulation acts to reduce heat transfer.

Studies have shown reflective insulation to reduce cooling costs by 5 to 10 percent in some homes.² That said, homeowners should note that this insulation is intended for hot climates and is ineffective against cold weather.

Ductwork

The purpose of ductwork is not to cool down your attic but this is something to consider, as improperly installed ductwork can cause air leaks that can prevent cooled air from being transferred throughout your home and seeping into the attic instead.

When considering your heating, cooling, and ventilation system, you’re likely to think about your furnace or air conditioner without considering the ductwork that extends throughout your home or attic space. Although ductwork channels for airflow are a major element in your home’s overall energy efficiency.

Consider the following factors relating to ductwork and how it could be affecting your home’s climate:

Losing cool air – Research from the National Renewable Energy Lab has shown that ductwork can add 25 percent to the overall cooling load of your home.³ Because of improper installation and sealing, you could lose a quarter of what you spend on AC every month.
Ducts attached to roof deck – In some homes, contractors make the mistake of installing attic ducts against the interior frame of your roof. In this scenario, ducts can become superheated from the roof, increasing the hot air circulating through your home. Ducts installed against your roof frame are also in danger of being punctured by roofers installing or repairing shingles.
The lower, the better – Keeping your ducts close to the floor of your attic is ideal for cooling purposes. The further they are from the hot roof, the cooler the air circulating through them is.

Keep Your Attic Cool With Attic Construction

Optimizing your home’s energy efficiency is a complex process. You can do some of the work DIY, but it pays to consult with professionals to solve your high energy costs. If you’re ready to cool down your home and save money on monthly bills, Attic Construction is here to help.

With more than a decade of industry experience, Attic Construction provides customized solutions like pest-proofing, insulating, and attic cleaning in Orange County, San Diego, or Pheonix. You can expect world-class service, fast estimates, and even emergency support. Contact us today to explore our offerings.

Sources:

US Energy Information Administration. Air conditioning accounts for about 12% of U.S. home energy expenditures. https://www.energy.gov/energysaver/air-sealing-your-home
Energy.gov. Radiant Barriers. https://www.energy.gov/energysaver/radiant-barriers
Energy Vanguard. 7 Ways to Improve Ducts in an Unconditioned Attic. https://www.energyvanguard.com/blog/7-ways-to-improve-ducts-in-an-unconditioned-attic/
Energy Star. Attic Air Sealing Project. https://www.energystar.gov/campaign/seal_insulate/attic_air_sealing_project
Energy Star. Attic Insulation Project. https://www.energystar.gov/campaign/seal_insulate/attic_insulation_project
House Logic. Passive Roof Vents: Helping Your House Breathe Easy. https://www.houselogic.com/organize-maintain/home-maintenance-tips/passive-roof-vents-helping-your-house-breathe-easy/
Energy Star. About Attic Ventilation. https://www.energystar.gov/campaign/seal_insulate/do_it_yourself_guide/about_attic_ventilation
Home Serve. Got Gable Vents? Here’s What You Need to Know About Your Attic’s Airflow. https://www.homeserve.com/en-us/blog/home-improvement/gable-vent/