People are often ambiguous about the terms “Spray Foam” and “Injection Foam” which leads to confusion. When spray foam and injection foam are used interchangeably, expansion rates can cause some uncertainty. Due to its open or closed cell structure, spray foam expands at different rates. However, there is no expansion with injection foam at all.
Although both products create an air seal, which increases the efficiency of a structure and makes it more comfortable, they differ in terms of the installation process, the products, and how they function.
Just so you know, Livingston Insulation has been installing spray foam across the Greater Toronto Area for more than 25 years. With their experienced team of professionals, they can help homeowners like yourself pick out the best kind of insulation for your house.
Installation of Spray Foam vs Injection Foam
The functions of Spray Foam and Injection Foam is the same although their installation procedure is completely different. Both products’ insulating properties are very good but the tools and methods used during installation vary by a large margin. You can also check this to know about different types of insulation.
How Injection Foam Insulation is Installed
As the name suggests, in this method foam is injected into the closed spaces and cavities of walls and roofs. This method has the biggest advantage which is the fact that you don’t need to demolish your drywalls and insulation can be installed from the outside.
At first, insulation injection foam is mixed in the trailer prior to installation. Injection foam such as ArmorFoam is used to insulate enclosed spaces. A mixture of resin, foaming agent, and water is transformed into injection foam insulation, resulting in a similar appearance to shaving cream consistency.
A perk of this insulation method is that it is not necessary to remove the old insulation in the walls, such as fibreglass. When injecting foam, the crews are likely to remove as much cellulose as possible if present from the walls before injecting the foam. By doing this, the injection foam will be able to fill in all the gaps and crevices in the wall.
It takes less time to prepare injection foam for installation than spray foam. If your house has aluminum or vinyl siding, you will need to remove a piece of it so that each stud cavity can be punctured to inject the foam. Foam injection is prepared in the trailer and then injected through a hose. Finally, the nozzle is inserted into the drilled hole so that the foam insulation can be installed. After installation is complete, Styrofoam plugs are inserted into the holes, and the siding is replaced.
In the case of a brick exterior, the foam is inserted through smaller holes in the mortar joints between each stud.
In the case of wood siding, if it is removable, the same method applies just like vinyl and aluminum siding. A hole must be drilled through the wood siding if the siding cannot be removed. Foam is injected into the holes, then wood plugs are used to fill the holes.
How Spray Foam Insulation is Installed
In any open cavity, spray foam insulation can be installed. For example, crawl spaces, attics, rim joists, and open wall cavities in newly constructed homes. In addition to spray foam, open-cell and closed-cell material can also be used in pole barns.
Spray foam is made by combining two liquids, which cause a chemical reaction to form a polyurethane foam. Both liquids are contained in drums or containers marked “A” and “B” for example. In typical spray foam systems, the “A” side is made up of methylene diphenyl diisocyanate and polymeric methylene diphenyl diisocyanate. A mix of polyols, blowing agents, catalysts, flame retardants, and surfactants can be found on the “B” side of the drum. Upon the mixture of the two drums, you get Spray Foam. Chemicals derived from petroleum extracts are the main ingredients in the spray foam we use.
A home’s old fibreglass or cellulose must be removed before spray foam can be introduced. The reason is that the spray foam is given a nice, clean surface to adhere to and can fill the space where it is sprayed. With this method, every crevice is filled and there is no possibility of air escaping.
Spray foam preparation takes longer than injection foam preparation. The reason for this is that things like furniture should be relocated to the room’s center position or completely taken out of the spot. To prevent spray foam from getting on floors and surfaces, the crew will wrap everything in plastic.
From the trailer to the home, two hoses are used to apply spray foam. In a small chamber, the “A” side and “B” sides of these two hoses are mixed together. The final mixture gets applied with the spray gun into the cavity.
The most common type of spray foam used in homes is open-cell spray foam. The material expands 100 times its original size, so it creates an airtight seal in every little space. A pole barn’s exposed walls are better suited to closed-cell spray foam.
R-Value and Sealing of Spray Foam vs Injection Foam
Even though the air sealing properties of injection foam and spray foam insulation is quite similar, their R-Value can vary.
Let’s start with the air seal. An air seal prevents air or vapour from passing through. Foam insulation can be used to create an air seal in your home to prevent air from moving in and out, regardless of whether it is spray or injection foam.
The cost of heating and cooling a home can be influenced up to 30% by leaks in the air. This is why making an air seal is so important. By using spray foam and injection foam, you can minimize energy loss in your attic, walls, crawl space, and rim joists, which will reduce your monthly energy bills.
A home air seal can also be beneficial for several other reasons. If any family member suffers from allergies or asthma or other issues during winter, a sealed home can keep out the irritants.
Moisture in your home is another factor to consider. Especially in areas such as crawl spaces, rim joists, and attics, foam insulation air seals will keep moisture from entering your home.
Then let’s talk about the R-Value. In simple terms, R-Value is a number that denotes the heat resistance of insulation. But only describing insulation by a number is often not sufficient. It’s important to know your insulation’s R-Value, but it’s not the determining factor of all things insulation as you may think.
R-Value is only one piece of the Puzzle with the Air seal being the other one. The role of an air seal is very important when it comes to insulation which is provided by spray insulation to prevent outside air from circulating inside your house.
R-values for open-cell spray foam insulation range from R-3.6 to R-3.9 per inch. The R-Value of closed-cell spray foam is R-6 to R-7. After injecting foam into the wall, it typically achieves an R-18 rating in total, which varies based on the size of the cavity.
Open Cell vs Closed Cell Spray Foam
Spray foam comes in open-cell and closed-cell versions, while injection foam is an open-cell foam that does not expand. This non-expansion is important because it would press against the interior of the exterior wall.
Both Open and Closed Cell Spray Foam have excellent insulation properties, but the differences come in what kind of structures they’re used in and efficiency.
Open-cell polymers are lightweight, pliable, and convenient to work with. Closed-cell tends to be much stiffer and denser. Because of this, the open-cell is better for houses because it can shift with the home’s foundation, whereas the closed-cell is nice and sturdy, so it is better suited for pole barns due to their exposed walls.
Now let’s talk about moisture permeability. An open cell is moisture-permeable by nature as there are spaces between the foam structure for moisture.
On the other hand, spray foam is 100 percent impermeable to moisture. You may think that is the best choice, but the product conceals leaks, and you don’t want that if you wish to know if your roof is leaking.
Home Insulation with Foam
As discussed above, the biggest difference between Spray foam and Injection foam insulation is how they are applied. Consider the structure it is going to be applied in, the desired R-values, and if you want an air seal or not. This will help you decide better on what kind of insulation you should get.
If you’re interested in either method or would like to know more about what kind of insulation you should get for your home, feel free to contact us and our team of professionals will be happy to help.
