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All About Insulation

Insulation is a material that acts as a barrier to heat loss and heat gain. When it comes to your home, insulation is most commonly used in roofs, ceilings, walls and floors. In most homes, insulation is one of the most practical and cost-effective ways to make a home cooler in the summer, warmer in the winter and more energy-efficient all year round. Furthermore, insulation can also reduce the amount of condensation in your home, which reduces mold, dampness and other unwanted air pollutants.
Insulation essentially works by stopping the transfer of heat. During the winter months, insulation prevents the cold air from outside infiltrating inside, which helps keep the home warm. During the summer, insulation works by trapping the cool, conditioned air inside the home, while simultaneously resisting the heat from outside. This is what makes insulation one of the most vital features of an energy-efficient home. Insulation really goes a long way in improving the comfort of your home by keeping a consistent indoor temperature, while also reducing the frequency and duration of air heating and cooling systems used in the home.

There are four common types of insulation that are used in residential homes, including

  • Blanket insulation. Blanket insulation is filled with mineral fibers, including rockwool and fiberglass. It comes in a rolled-up form.  
  • Polyurethane and polyisocyanurate foam insulation. This type of insulation is sprayed into the crevices and cracks of a home to prevent air leakage.
  • Loose fill insulation. Loose fill insulation is made of cellulose, rockwool and/or fiberglass. It comes in pellets or fibers.
  • Rigid insulation. This type of insulation is typically used in boards or pipe fittings and is usually used to insulate wall sheaths and foundations.

Now that you understand the basics of insulation, let us look further into the benefits of insulation, the different types of insulation, knowing when you need to insulate your home and more.

What’s on this page:

The Benefits of Insulation

Understanding the Different Types of Insulation

  • Foam Insulation
  • Blanket Insulation
  • Loose Fill Insulation
  • Cellulose or Fiberglass? 
  • Rigid Insulation

Determining if Your Home Needs Air Sealing and Insulation

How Insulation and Air Sealing Can Help Lower Your Utility Bills

How Much Should You Pay for Quality Insulation in Maryland?

How Much Should You Pay for Quality Insulation in Virginia?

Finding the Right Insulation Contractor


The Benefits of Insulation

Insulating your home comes with a range of benefits, including increased comfort in your living environment and reduced utility bills. Let us look further into the advantages of insulation and why it is a necessity for any energy-efficient and comfortable home.

Cost Benefits

A large reason why homeowners choose to insulate their home is thanks to the cost-saving benefits. Insulating your home makes it much more-energy efficient and this is because insulation works to keep a home cooler in summer and warmer in winter. In turn, this reduces the amount of heating and cooling expenses required to keep your home temperate and comfortable all year round. As a result of adding insulation, your energy bills stay low and your wallet stays full.

Comfort Benefits

Adding insulation to your home is an effective way to improve the comfort of your living environment. This is because insulation helps regulate the temperature of your home, making it a more comfortable and enjoyable place to be, especially in areas where the weather can be extreme. Furthermore, insulation also has the added benefit of increasing the sound control of your home. Insulation creates a sound barrier around your house, keeping unwanted noises out and protecting your privacy by keeping the sounds from inside your home from being heard outside. Furthermore, insulation also acts as a moisture barrier, which keeps unwanted moisture out of your house and protects the inside of your home and all of your possessions.
Environmental Benefits

Insulating your home also helps you reduce your environmental impact. This is because when your home is insulated, you will not need to use as much energy for heating and cooling your home. Not only does this reduce your carbon footprint, but it also reduces the amount of chemicals released into the environment from air conditioning units.

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Understanding the Different Types of Insulation

Foam Insulation
Foam insulation is a relatively new method for insulating a home. There are different types of foam insulation, but one of the most common types is polyurethane foam, which you spray into ceilings and walls. It quickly expands and forms an air tight seal. You can use it to insulate a new home or add it to the insulation of an existing one. It is the ideal insulation to use when dealing with small crevices and cracks.
Foam insulation comes in a variety of forms:

  • Aerosol cans with one-part formulas, ideal for insulating doorways.
  • Low pressure sprayers with two-part formulas, ideal for smaller jobs.
  • Two-part kits that need to be applied with high-pressure sprayers, ideal for large insulation jobs.
What are the advantages of foam insulation?
  • Energy efficiency. Foam insulation expands naturally after applying it, which helps seal off any crack or crevices.
  • Durability. It does not wear and tear as easily as normal fiberglass insulation.
  • Ideal for different types of damage. Foam insulation keeps away pests, mold and mildew.
What are the disadvantages of foam insulation?
  • Cost. Due to its energy efficiency and durability, it can be more expensive than other options.
  • Can be difficult to apply. It is a job best left to professional insulation installers.      
  • Messy installation. Even when carried out by professionals, foam insulation is tricky to install and it is easy to miss the target.

Blanket Insulation

Fiberglass insulation that comes in the form of a blanket is the ideal type of insulation for new construction and spaces that are easy to access, such as attics. Blanket insulation comes in rolls or batts, making it easy to cut and fit in any space, including around electrical boxes and pipes.
What are the advantages of blanket insulation?

  • Affordable. Blanket insulation is cheaper than foam.
  • Easy to install. It is very easy to install blanket insulation.
  • Easy to find professional installers. Fiberglass has been around for longer than foam, meaning it is easier to find people who have experience in installing it properly.

What are the disadvantages of blanket insulation?

  • Lower energy efficiency. Fiberglass has a lower R-value and is not as efficient as spray foam.
  • Less durable. Blanket insulation often settles and breaks down faster, meaning its thermal protection decreases over time.

Loose Fill Insulation

Loose fill insulation, also known as blown insulation, is one of the most commonly used types of insulation. It can be made up of a variety of materials, such as: cellulose, fiberglass, polystyrene beads, perlite or vermiculite.

What are the advantages of loose fill insulation?

  • Versatility. Loose fill insulation can be used in new or existing homes and is very versatile due to its malleable nature.
  • Sound-proof. The fiberglass material in loose fill insulation is ideal for sound-proofing.
  • Affordable. It is one of the most affordable insulation materials.
What are the disadvantages of loose fill insulation?
  • Fast decay. Loose fill insulation is easily affected by convective air movement, which makes it decay quicker over time.
  • Lower pest control. It does not effectively deter pest or insects when compared to foam or blanket insulation
  • Can be a fire hazard. A lot of the materials used in loose fill insulation are not fire-proof.

Cellulose or Fiberglass Insulation?

Chances are, you have heard a range of differing opinions when it comes to loose fill insulation and whether fiberglass or cellulose is better. Truthfully, many contractors out there will hype up the materials they sell, and their options are generally based on purchasing decisions rather than scientific facts. Here are our recommendations, which are actually based on scientific research and the real, quantifiable results we have achieved in our clients’ homes.

Why choose cellulose insulation?

While different materials may work best in different places around your home, in terms of the best loose fill insulation for attics, we believe borate only stabilized cellulose is best. Here is why:

  • Better performance and a higher R-value than fiberglass
  • It is made from recycled materials, making it environmentally friendly
  • Borates are an effective insecticide
  • Cellulose is less of an inhalation hazard compared to fiberglass
  • The one disadvantage of cellulose is it is more expensive than fiberglass

Why choose fiberglass insulation?

On the other hand, many industry experts call out the fact that loose fill fiberglass still dominates the new construction house market. However, this might be due to the fact that builders are under extreme pressure to deliver beautiful new homes, while also cutting costs and staying within budget. Here is why you might consider fiberglass, or might steer clear of it:

  • Fiberglass insulation is cheaper than cellulose
  • Fiberglass is subject to convective air movement, which leads to degradation of its R-value
  • Fiberglass is not a good insecticide or pest preventative
  • Fiberglass can cause skin and lung irritation

Rigid Insulation
Rigid insulation is another popular insulation choice. The most common materials used in rigid insulation are: polyisocyanurate, expanded polystyrene, bead board, EPS, XPS, rigid fiberglass and phenolic foam boards.

What are the advantages of rigid insulation?

  • Energy efficiency. Rigid insulation provides effective thermal comfort all year round.
  • Breathability. Air moves around rigid insulation, not through it, which makes it a good choice for air sealing your home.
  • Durability. It last longer than loose fill insulation and maintains its form and properties.
What are the disadvantages of rigid insulation?
  • Expensive. The thermal comfort and durability of rigid insulation comes with a price. However, if you live in a place with cold winters and hot summers, it may be a worthwhile investment to save on future heating and cooling bills.
  • Hard to find. Rigid fiberglass can be hard to find and is not always readily available.
  • Prone to sunlight damage. Some of the materials used in rigid insulation may degrade when exposed to sunlight.

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Determining if Your Home Needs Air Sealing and Insulation

It is not always obvious when your home needs air sealing or insulation. There are some ways you can tell, such as drafty rooms and inflated utility bills, but sometimes it is not so apparent. Here are a few tests you can carry out to determine if your home needs air sealing and insulation

1. The Age Test

Chances are, if your home was built prior to 1980 and the insulation has not been upgraded or added to, it is time for new insulation. Your home will certainly benefit from additional insulation and the advancements in insulation technology.

2. The Comfort Test

Is your home comfortable? Do you still use blankets in the winter even when the heat is on high? Is your home still too hot in the summer despite having the AC on all day? If so, improper insulation and air leakage is likely the cause, which is not only reducing the comfort of your home but also increasing your utility bills.

3. The Paper Test

The paper test is an easy and effective way to determine if your home needs air sealing. Slide a piece of paper between exterior doors jambs and around closed windows. If the paper effortlessly fits in any gaps or crevices, you can bet that your heated or cooled air is escaping just as easily

4. The Dirt Test

If there is an accumulation of dirt on top of your insulation (rim joist pockets in the basement and top plates in the attic), or along the outside walls of your carpeting, it is likely you have air leakage. Insulation is supposed to work as a filter to trap dust in the air as it flows in and out of the home. Air leakage around exterior walls and floor joists will cause dirt to accumulate. These dust tracks are obvious signs of air loss/gain and inefficiency.

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How Insulation and Air Sealing Can Help Lower Your Utility Bills

Did you know that improper insulation and air leakage are two of the most common causes for ineffective heating and cooling in American homes? In fact, air leakage accounts for 15−25% of winter heat loss in the typical home. Furthermore, statistics from the Department of Energy show that heating and cooling makes up 48% of total energy use in the average household. Safe to say, the impact of air leakage and ineffective insulation can be enormous, especially when it comes to your utility bills. However, with proper air sealing and insulation, you can significantly reduce your utility bills and increase the comfort of your home.


Insulation works by inhibiting the transfer of heat. In winter, it stops the cool air from outside coming inside. During summer, insulation helps trap cool, conditioned air inside the home while resisting the heat from outdoors. This greatly reduces your utility bills as it decreases the frequency and duration of time you use your home’s heating and cooling systems.

Air Sealing

Air leakage is the process of outside air entering, and conditioned air exiting, your home. Reducing or better yet, eliminating these air leaks means your home can maintain a consistent temperature, which in turns helps you save significantly on your heating and cooling costs. Caulking and weather-stripping are two common ways to air seal your home, and can even deliver a significant return on your investment in as little as a year.

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How Much Should You Pay for Quality Insulation in Maryland?

If you live in Maryland, you might be questioning whether you need insulation in your home. Here are just a few reasons why quality insulation is vital for all Maryland homeowners. As you now know, insulation works to stop the transfer of heat, making it one of the most important features of an energy-efficient home. There are different types of insulation, and the type you need will depend on the unique requirements of your home and where you live. Maryland has a milder climate, meaning your needs for heating and cooling are relative. However, it is still important that the insulation you choose for your home meets the minimum R-Value guidelines for Maryland.
As you would have read above, insulating your home comes with a variety of great benefits, such as:

  • Reducing your heating and cooling bills by as much as 20%
  • Reducing your energy usage by 10%
  • Greater resale value when you sell
  • Improves the durability of your home by reducing the humidity and the amount of mold that accumulates

When it comes to determining the cost of quality insulation in Maryland, there are a few factors that are involved, such as:

  • Type of insulation
  • R-Value of the insulation
  • Any other work required to complete the project
  • How the insulation is installed

These are just some of the factors that will determine how much quality insulation will cost in Maryland. We always advise you ask a professional home improvement contractor to evaluate the specific needs of your home so you can get the most accurate estimate.

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How Much Should You Pay for Quality Insulation in Virginia?

According to manta.com, the average price homeowners in Virginia paid for insulation in 2016 was $433. However, the price can be anywhere between $400 and $1,700, according to fixer.com. While this is a significant difference, it is important to remember there are many factors involved in calculating the final insulation installation price. For example, not only do you need to consider the cost of materials (which comes down to the type of insulation you choose), but you must also consider the cost of labor, insurance, business costs and specialty machinery. Oftentimes, electrical rewiring is a necessary part of insulation upgrades, so this is something you also need to factor in to the cost. Other elements you need to consider are:

  • Repairs to rotten wood
  • Adding or extending central heating to the attic
  • Adding seals around chimneys and framing
  • Having a professional check for water leaks
  • Plumbing work

As with anything, it really does depend on the current state of your insulation and home. If you are a Virginia homeowner, we advise you ask a qualified home improvement contractor to evaluate your needs first, so you can have an accurate budget before you begin your project.

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Finding the Right Insulation Contractor

Insulating your home can be a big job, which is why it is vital you find the right contractor for the project. There are a few ways to determine whether your insulation contractor is right for the job, which we have outlined below.

The Contractor Uses Advanced Diagnostic Tests 

The best professional insulation contractors will use advanced diagnostic tests to determine where to add insulation in your home, and how much insulation is needed. This takes the guess work out of how much insulation you need to purchase, which saves you money because you are only buying the exact amount of insulation needed.

The Contractor Understands the Importance of R-Values

Before adding any new insulation, it is important the contractor determines the R-values of existing insulation. That way, you as the homeowner can make an informed decision on whether you want to add more insulation on top, or to remove the existing insulation and replace it with new insulation. However, if the existing insulation is damaged, loose or moist, it is usually best to remove it straight away and replace it with new insulation. 

Furthermore, it is important your contractor knows the importance of combining the R-value of the new insulation with the R-value of the old insulation so it equals the recommended level for your area. Double checking this R-value will ensure you get what you pay for.

The Contractor is Certified and Insured 

The best insulation companies and contractors are always certified and insured. You are easily able to verify a contractor’s certification by checking the Insulation Contractors Association of America (ICAA), but it is a good idea to ask the insulation contractor if they are certified and insured before they start any work in your home. If something goes wrong during the insulation installation project and your contractor is not insured, you could be in trouble.

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