Adding Insulation to Your Attic: Everything You Need to Know

You’ve tried everything you can think of to reduce your energy bill—unplugging kitchen appliances when they’re not in use, cutting back on the hot water in the shower, and diligently turning the lights off after leaving a room. But, despite all of this effort, you’re still not noticing a decrease in your household energy costs. Turns out, the culprit of your high power bill could be right over your head.

Take a peek into your attic with a flashlight. Do you see any fluffy bats of fibers or a thick blanket of downy-looking tufts? If not (or if “fluffy” or “downy” aren’t words you’d use to describe whatever’s up there), your attic needs to be insulated. Without proper attic insulation, your HVAC system has to work that much harder to keep your home cool in the summers and warm in the winters. 

Now that you’ve discovered the prime suspect in the case of the high energy bill, what comes next? In this guide, we’ll review everything you need to know about adding insulation to attic spaces. Check out our crash course below. 

What is Insulation?

To understand insulation, it’s helpful to understand what it’s regulating: heat. There are three kinds of heat flow:

  • Conduction, which is when heat moves from one material to another
  • Convection, which when heat is transferred in liquids and gases
  • Radiation, which travels in a straight line until something absorbs its heat energy

Insulation prevents the heat energy in your attic from flowing into your home’s interior via conduction through wood, drywall, and other building materials.1 Keep in mind that you can have both wall and attic insulation, both serving similar purposes within a home. For the sake of this article, we are going to specifically be focusing on the attic space. Since it improves your home’s resistance to heat conduction, insulation’s capacity for preventing reduction is measured by its R-value. 

While R-values aren’t as simple as “thicker insulation equals more heat resistance,” a higher R-value generally indicates a higher insulation ability to prevent heat loss and support attic ventilation. 

Fiberglass Insulation

Insulation can be made out of a variety of materials, but there are two frontrunners in terms of both popularity and availability: fiberglass and cellulose.2

Fiberglass is a fibrous, or “fluffy,” material made out of tiny shards of glass. In the case of blown-in insulation (more on that later), fiberglass insulation is made from molten glass, which usually contains some portion of recycled materials. 

Fiberglass insulation is available in a variety of densities, and more dense fiberglass generally has a higher R-value. As one of the most widespread insulation materials in the industry, insulation professionals are experts on both choosing the right product density and the best attic insulation installation method. 

Cellulose Insulation

Another popular insulation material, cellulose, is widely used in homes and commercial buildings. A few things to know about cellulose: 

  • It’s made of tiny shredded paper fibers.
  • These paper fibers are usually created from recycled newspapers.
  • The natural cellulose fibers in paper help the shreds bind to themselves and surfaces.

Cellulose insulation is often treated (or combined) with borate or ammonium sulfate to both decrease its flammability and repel pests. However, cellulose is environmentally friendly, effective, and more economical than other insulation materials, making it a commonly-explored option for homeowners on a budget. 

Batt Insulation

Fiberglass insulation can be created into two varieties of insulation which require different installation methods: batts (also called rolls or blankets) and loose-fill (also called blown-in insulation). 

Batt insulation is likely what comes to mind when you think of insulation. Fiberglass is pressed together to form batts of various thicknesses that are cut into pieces and rolled up. Then, installers lay them between the joists on an attic floor. 

Batt insulation doesn’t require any special equipment to install, but it does require the expertise of trained and experienced insulation installers. Insulation installers ensure optimal coverage of the entire attic surface, which requires careful measurements and close attention to detail.

Blown-In Insulation

Loose-fill insulation is blown into attic spaces with a specialized blower system, which is why it’s also widely known as blown-in insulation. 

Both cellulose and fiberglass materials can be used to make blown-in insulation, which is fibrous and adheres to attic surfaces. Blown-in insulation is an excellent solution for:

  • Attics with obstructions, like an air handler
  • Attics with tons of nooks and crannies to insulate, such as those in a vaulted ceiling

Insulation installers use a hose with a specialized blower to disperse the loose-fill insulation around an attic space, making sure that the thickness and coverage are consistent throughout the entire attic surface. 

What Does the Insulation Process Look Like?

From start to finish, the insulation process is quite straightforward, especially for homeowners hiring insulation professionals. After agreeing to a proposed price for the work, skilled technicians make adding insulation to attic spaces look easy.

But, since you likely won’t be accompanying them into your attic, here’s what all the overhead ruckus will entail:

1. Existing Insulation is Removed

If adding insulation to attic spaces that have never been insulated before, this step is irrelevant. But in cases where a home’s attic insulation is very old, ineffective, or infested with pests, the existing insulation has to be removed before the other installation steps can begin. So what does the attic insulation removal process look like?

Insulation removal is pretty simple. There are two methods to get the job done:

  1. Installers use a large, high-powered vacuum to suck existing loose-fill insulation out of your attic and into heavy-duty insulation removal bags.
  2. For batt insulation, installers bring the insulation removal bags into the attic and remove each batt from the attic surface, filling the bags to be disposed of responsibly. 

Insulation removal professionals wear significant protective gear during this process to protect them from dust inhalation and exposure to pests. The attic insulation removal cost may vary depending on the home. If you are considering removing your attic insulation on your own, it is highly recommended to leave this job to the professionals. 

2. Pest Debris is Removed

During and after the old insulation removal process, the insulation installers will search for signs of live pests, dead pests, and pest droppings. They’ll remove all traces of a pest infestation, which is the first step in preventing future unwanted tenants from moving into your attic. 

Once any rodents are dealt with swiftly and thoroughly, installers take further steps to keep rodents out of your attic and away from your insulation. 

3. Rodent-Proofing is Installed

Not only will installers ensure the thorough expulsion of rodents, but they’ll seal up any visible entry points in your attic and add rodent-proof barriers to keep pests out and also reduce moisture within your attic space. 

Why is this step so important?

  • Rodents around the world transmit over 30 different diseases, and even their droppings present a health risk for their human roommates.3 
  • Unfortunately, insulation is a five-star resort for rodents. It gives them a place to burrow, store food, and protect their young. 

To prevent further break-ins and infestations, insulation contractors will use wire mesh and other materials to block pest entry points and protect your attic floor from destruction by pests before blowing in loose-fill or laying batts. 

After all, what good would be done just by getting rid of the existing pest evidence? Rodent-proofing your attic not only keeps your insulation from being destroyed, but also protects the health and well-being of you, your family, and your pets. 

4. Insulation is Laid or Blown-In

Once your attic’s old insulation and any remaining pests are put out to pasture, and your attic is protected against any other wandering rodents, insulation installation can finally begin!

If you’ve chosen batt insulation for your attic, the installers will begin rolling out the batts between all of your joists. They’ll take special care to make sure that all nooks and crannies are covered. 

If you’ve chosen blown-in insulation, the installer will pull the blower hose into your attic, begin blowing loose-fill insulation onto the entire surface of your attic floor, and ensure that the material covers each area consistently. 

Once installation of the new insulation is complete, installers will clean up their extra materials, pack up all of their tools and equipment, and leave you with a freshly insulated attic. 

Can You DIY Attic Insulation?

While the processes above sound pretty straightforward, it’s not recommended that novices or hobbyists insulate their own attics. Adding new insulation to attic spaces requires careful measurements, safety precautions, and (sometimes) specialized equipment. 

Here are some additional reasons to avoid DIY attic insulation: 

  • While removing old insulation from an attic, DIYers may not know what to do with their insulation debris after it’s stripped away. Insulation needs to be disposed of responsibly, and professionals are best equipped to handle the waste. 
  • Handling pests (dead or alive) without professional qualifications and safety gear could result in health hazards. Untrained eyes may also not be able to spot hard-to-find rodent entry points. 
  • Even though installing batt insulation doesn’t require special tools, it does require precision for adequate surface coverage. Plus, installing blown-in insulation requires a specialized blower system—equipment that isn’t available to the general public. 

While the potential of a well-earned insulation feather in your DIY cap may be tempting, hiring a professional insulation installer will ensure that your attic is insulated with the right materials, protected effectively against pests, and well-covered with insulation. 

Keep Energy Costs Low and Pests Out with Attic Construction

Adding insulation to attic spaces is an excellent way to reduce stress on your HVAC system, lower your energy bill, and keep pests out of your attic. 

At Attic Construction, we want you to see all of these outstanding results and more. Since 2011, we’ve been providing professional attic insulation installation services to families and business owners in our community. Whether its Phoenix insulation installation, Orange County rodent proofing, or San Diego attic cleaning…we’ve got you covered in multiple states! We’re confident that our commitment to quality—in materials, installation, and customer service—makes us the best choice for your attic insulation needs. 

Let us help you cut back on energy costs, invest in your home, and increase your comfort. Contact us for a free consultation. 



  1. US Department of Energy. How Insulation Works. 
  2. US Department of Energy. Insulation Materials. 
  3. US Centers for Disease Control and Prevention. Rodents. 

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