“R-Value” indicates how much resistance there is to heat flow. The higher the value, the better the insulating resistance. By reading the R-value, you can understand how insulation prevents heat transfer. The R-value is calculated based on the thickness and density of the insulation material.
Most cellulose insulation products on the market have an average R-value of 3.4 per inch. This is lower than other options, but you can call a few insulation companies to get quotes and see what they recommend.
What is Cellulose Made of?
Cellulose has become the most popular type of insulation because of its affordability. Cellulose insulation is made of recycled paper products and is one of the most environmentally friendly types of insulation available today. Fire retardants and insecticides are often used on the insulation, usually containing recycled newspaper, cardboard, and other paper products.
Types of Cellulose Insulation
There are four types of cellulose insulation: loose-fill (blown-in), wet-spray foam, batt-based, and dense-packed.
Loose-fill Cellulose
Loose-fill (also called Blown-in cellulose, Dry Cellulose Fiber) is a type of cellulose insulation made of recycled materials that have been shredded into tiny pieces. It is usually treated with fire retardants and insecticides and often contains recycled newsprint, cardboard, and other paper products.
Loose-fill cellulose insulation is an excellent option for insulating attics, unfinished basements, and crawl spaces. It can also be used in wall cavities but is not recommended for regularly wet areas. Because it is made of small pieces of paper, it can easily be blown into tight spaces and crevices.
Generally, the installation will require a blowing machine, where dry cellulose fiber insulation is blown into the desired area through a hose, and then the site is sealed. This insulation is excellent for insulating attics, unfinished basements, and crawl spaces. It can also be used in wall cavities but is not recommended for regularly wet areas.
Wet-Spray Cellulose
Spray foam cellulose (Wet-spray cellulose) insulation is made with mixed foam and then sprayed into the attic or walls. It is more expensive than blown-in insulation but can provide better insulation because it forms a seal around pipes and wires.
The binder substance ensures that the cellulose adheres to the sprayed surface. Wet-spray cellulose can therefore be used to seal and insulate an area simultaneously.
Batt & Blanket Cellulose
This is similar to fiberglass batts, and Batt-based cellulose can absorb and release moisture without changing how well it works as a thermal insulator. It lets air in and allows a lot of vapor to pass through. Batt cellulose insulation is easy to install and provides excellent thermal and acoustic performance.
Dense-Packed Cellulose
This cellulose insulation is commonly used to insulate walls and ceilings and doesn’t need ventilation or a vapor barrier. Instead, this technique squeezes as much material as possible into a specific area.
The following video is a detailed demonstration of how dense-pack cellulose is installed.
Why R-Value is Important with Cellulose Insulation?
When it comes to insulation, the R-value is one of the most important factors to consider because the R-value of an insulating material indicates how efficiently it prevents heat transfer. The higher the R-value, the better the insulation will prevent heat loss.
The R-value of cellulose insulation can vary slightly from manufacturer to manufacturer, so it’s best to talk to the manufacturer to get an accurate R-value. However, R-values for cellulose insulation are typically listed in the product’s technical specifications.
How to Calculate the R-value of Cellulose Insulation?
When comparing the thermal resistance of different insulating materials, you need to look at their R-values per inch of thickness. The following insulation thickness chart (R-value chart) helps you understand Cellulose R-values based on insulation types with different thicknesses per inch.
| Type of Fiberglass Insulation | Per Inch | 4 Inch Thickness | 6-inch Thickness | 8-inch Thickness |
| Loose-Fill Cellulose | R-3.4 | R-13.6 | R-20.4 | R-27.2 |
| Wet-Spray Cellulose | R-3.4 | R-13.6 | R-20.4 | R-27.2 |
Is Cellulose a Good Insulation?
Cellulose insulation is a popular choice for homeowners. Many homeowners choose cellulose insulation because it is a better option for tight spaces.
Cellulose insulation is made from recycled paper materials. As a result, it is a more environmentally friendly insulation material than some other options on the market. Cellulose also contains no toxic chemicals, making it safe for homeowners and the environment.
What are the Advantages of Cellulose Insulation?
There are several benefits to using cellulose in your home’s insulation. Some of the key benefits include:
- Cellulose insulation is affordable and non-toxic, making it a popular choice for homeowners. It can also be treated with fire retardants and insecticides to make it more durable.
- Cellulose insulation is an excellent choice for reducing air leakage (also known as convection) in your home. It forms an airtight seal when appropriately installed, which helps keep your home comfortable and energy-efficient.
- Cellulose insulation is made of recycled materials. This means that it is environmentally friendly and helps to reduce waste.
What are the Disadvantages of Cellulose Insulation?
While cellulose insulation does have several advantages compared to other alternatives on the market, there are a few disadvantages to consider before deciding if it is the right choice for your home.
- It has a lower R-value than other options, such as Fiberglass insulation. This means it is not as effective at insulating your home as other choices.
- Air leaks in cellulose insulation can be a big problem. The R-value can be significantly reduced if there are any air leaks. It is, therefore, essential to ensure that the insulation is installed correctly and that there are no air leaks.
- Cellulose insulation is prone to mold growth because it is an organic material. Mold can grow on any organic material, given the right conditions.
- Cellulose insulation can be challenging in tight spaces compared to other alternatives, such as spray insulation.
- Cellulose insulation may not be as durable as some of the other available options. It can be treated with fire retardants and insecticides, but it may not be as resistant to damage as other types of insulation.
Where can you Use Cellulose Insulation?
Cellulose insulation can be used in various places in your home insulation, including the open attics, walls, and between the studs.
Attic
When putting cellulose insulation in your attic, you should consider the weather in your area. If you live in a warmer area, choose insulation with a higher R-value to keep your house from getting too cold.
Cellulose insulation can be treated with fire retardants and insecticides to make it more durable, but it may not be as resistant to damage as other types of insulation. Dense-packed cellulose is an excellent option for homes with limited space, as it can be packed into an enclosed wall or tight spaces to provide better insulation.
One area often forgotten is the attic floor where the wall plates intersect. This is a critical area to seal because it can help prevent heat loss. To install cellulose, you must cut it to fit around the wall plates. Wear gloves and a mask when doing this, as the insulation can irritate the skin and lungs.
Walls
Blown-in cellulose can be used on walls using a blowing machine. The cellulose insulation is blown into the desired area through a hose, and then the area is sealed. When installing cellulose insulation on walls, it is critical to consider the climate in your area. Choose insulation with a higher R-value if you live in a warmer place. This will make sure that your home is adequately insulated.
Installing cellulose in wall cavities can be a challenge, but it is an excellent way to improve the insulation in your home. When installing cellulose insulation, it would be best to use a blowing machine to blow cellulose into the desired area. Considering the climate in your area before installing cellulose insulation is essential, as it may not be as effective in warmer climates.
Ceiling
Cellulose insulation can be used on ceilings in a variety of ways. One way to install it is by blowing it in with a machine. Another way to install it is by spraying it on. When putting cellulose on ceilings, you need to consider the weather where you live.
If you live in a warmer climate, you may want to choose a type of insulation with a higher R-value to ensure your home is adequately insulated. Cellulose insulation can also be used on a basement ceiling to ensure the seal of all roof leaks to block any air infiltration points.
How to Install Cellulose Insulation?
When installing cellulose insulation, it is essential to follow industry standards. This will ensure that your home is properly insulated and that there are no air leaks.
Cellulose insulation can be installed in various ways; plan the entire space to ensure complete coverage and apply adequate thickness of Cellulose. There are three ways to install cellulose insulation: blowing it in with a machine, spraying it on, or installing it in batts.
Blowing It In with a Machine
Blowing it in with a machine is the most common way to install cellulose insulation. Considering the climate in your area before installing cellulose is crucial, as it may not be as effective in warmer climates. Cellulose insulation can be treated with fire retardants and insecticides to make it more durable, but it may not be as resistant to damage as other types of insulation.
Spraying It On
Another way to install cellulose is by spraying it with a high-pressure nozzle, similar to a pressure washer. This method is suitable for larger areas such as ceilings. You must use a particular spray gun to apply the insulation evenly when spraying cellulose insulation. Wear protective gear, including safety glasses, gloves, and respirators, when using this method.
As the cellulose insulation is put into the wall cavity, a water mist is used to wet the surface. Water makes the material sticky, which makes the insulation fibers stick to the building’s frame even more.
You may start by air-sealing all the leaks in your attic insulation, especially around the pipes, fan housings, electrical lights, plumbing penetrations, wall framing, wires, and junction boxes. Also, remember to seal the parts of the attic floor where the wall plates meet. In the same way, you need to carefully seal all the leaks in the ceiling so that air can’t get in. Fill all the cracks and holes in the wall if you can.
Installing It in Batts
The third way to install cellulose insulation is by installing it in batts. This is the easiest way to install cellulose and is suitable for smaller areas. This method is often used when insulating walls. When installing cellulose insulation in batts, you will need to cut them to size and then install them between the studs.
Can you Install Cellulose on an Existing Cellulose Insulation?
You can install cellulose on existing insulation. If you are installing cellulose on top of another layer of cellulose insulation, you must ensure that the two layers are evenly spaced. You can use a straight edge and a sharp knife to cut the insulation.
What are the Alternatives to Cellulose Insulation?
Several alternatives to cellulose insulation include fiberglass insulation, foam insulation, and mineral wool insulation. All these types of insulation have their benefits and drawbacks, so it is vital to choose the type best suited for your needs.
Fiberglass Insulation
Fiberglass insulation is made from fiberglass strands wrapped in a paper or foil backing. It is one of the most popular types of insulation and is available in various thicknesses. Fiberglass insulation is easy to install and is resistant to moisture and pests. However, it can be damaged by fire and may not be suitable for some climates.
Foam Insulation
Foam insulation is made from polyurethane or polyisocyanurate foam. It is available in various thicknesses and can be used for walls, ceilings, and floors. It is resistant to moisture, pests, and fire. However, it can be expensive to install and may not be suitable for some climates.
Mineral Wool Insulation
Mineral wool insulation is made from wool, or rock wool fibers spun into yarns or mats. It is available in various thicknesses and can be used for walls, ceilings, and floors. Mineral wool insulation is resistant to moisture, pests, and fire. However, it can be expensive to install and may not be suitable for some climates.
Does Cellulose Insulation Resist Fire?
Cellulose insulation does resist fire. However, it is essential to note that not all cellulose insulation is treated with a chemical treatment to make it fire retardant, so be sure to choose a type that is treated with fire retardants if you are concerned about fire safety.