In a broad sense, closed cell foam is semi-impermeable and restricts the flow of air and is less water absorbent, while open cell foam is semi-permeable and allows air and water to pass through it. Depending on your situation, one may be a more effective barrier than the other.
Closed cell foam has a higher R-value than open cell foam, usually about 6.0 per inch. But some closed cell foams, like Tiger Foam's E84 Closed Cell formula, have even higher ratings that go up to almost 7 per inch. This higher rating makes closed cell foam better at keeping heat in or out of a structure.
Cons: It's not suitable for extreme temperatures. Open cell has a low R-value, which is the measurement of how effective a type of insulation is. The open cell R-value is 3.5-4 per inch, which works for moderate climates but not colder ones.
It Can Lead to Mold
Spray foam insulation mold problems are quite common. Especially with closed-cell spray foam, which is rigid. Mold and mildew can begin growing behind the insulation which can go unnoticed until it's already become a huge problem.
Closed cell foams are the most popular type of insulation used in remodeling and new construction applications. They can provide support to the structure due to the composition of their cells. They protect against water damage, and generally provide a higher r-value per inch than open cell foams.
A vapour barrier is not necessary with closed-cell foam but with open-cell spray foam such as Icynene®, it is sometimes required. Any air that migrates though a building envelope will carry water vapour. As Icynene® spray foam creates a seamless air-seal, it controls air leakage and the moisture in the air.
Keep in mind that while open cell spray foam can be used anywhere, it does not create a vapor barrier like closed cell spray foam does. Thus, any structure using open cell spray foam (whether it is in the north or the south), would need an additional vapor barrier to prevent condensation from forming.
Both types of spray foam insulation can last anywhere from 80 years to 100 years, with closed cell spray foam having a slight edge in terms of durability. For most families, this represents the lifetime of the house and then some!
Cellulose will begin degrade if it's not dried quickly, and it can start to grow mold. Spray foam tends to be water-resistant, especially the closed-cell variety, but it can trap water between its surface and nearby materials like wood wall studs, encouraging them to rot.
Avoid using the foam near any ceiling lights or heating appliances. If you spray the foam near a ceiling light, for example, there is a chance that it could catch fire due to the flammable nature of the spray. Additionally, it could also cause damage to the light itself if it cures around any wiring.
In terms of fire resistance, closed cell spray foam is class 1 fire rated. Meaning it won't serve as a catalyst in cases of fire and it can also self-extinguish after the flame is removed.
The best types of home attic insulation are open cell spray foam, fiberglass, and cellulose. Cellulose is the oldest insulation material used for not only the attic but other areas of the home as well. Cellulose can be either a loose-fill or blown-in material and is primarily made of recycled newsprint or denim.
Therefore providing mechanical fresh air ventilation is especially important in spray foam houses. Mechanical ventilation systems allow a constant flow of outside air into the home and can also provide filtration, dehumidification, and conditioning of the incoming outside air.
Open cell will accommodate seasonal movement, so when your house shifts and settles the foam will move with it. The spray foam allows water to move through it without retaining it or losing insulation properties. It has vapor permeability. Open cell spray foam cannot sustain mold.
When using closed-cell foam in walls, it is generally considered sufficient when 2 to 3 inches are sprayed. Open-cell foam in walls would not be sufficient with just 2 inches, requiring at least 3.
Spray foam insulation is one of the best ways to insulate your home, despite some drawbacks. It usually costs more than other forms of insulation, but within a few short years you'll have paid the cost back and will be able to enjoy reduced energy bills for a long time.
When using a do-it-yourself foam insulation kit, you will need to ensure you are spraying the material where you want it to be. Foam, when mixed correctly, will stick to everything and isn't easy to remove. Keep in mind you will need to wear a hooded suit, gloves, a face mask, and eye protection.
While closed-cell foam does prevent both air and water from seeping in, it's not cost-effective if you only need an airtight seal. Open-cell foam does the same job at a more affordable price. If you're looking for your product to retain its shape after compression, closed-cell foam is not the way to go.
However, you should store both open cell and closed cell spray foam components at a temperature of at least 60 degrees Fahrenheit. When you apply the spray foam, you want an ambient air temperature, and substrate temperature of at least 40 degrees Fahrenheit.
For closed cell spray foam, you'll want to make sure that your foam is 2-3 inches thick on the walls and 4-5 inches thick on the roof deck.
Yes, you can sleep in your house after installing spray foam. However, the curing time for spray foam should be at least 24 hours after installation.
Since closed cell foam is denser than open cell foam, it will take more material to cover the same amount of space so it will ultimately cost more. Because there is more material being used, there also could be more labor cost to get it installed.
It's important to note that some insulation materials, such as spray foam, do not require an air gap. However, if you're using traditional insulation materials such as fibreglass or mineral wool, it's important to follow the manufacturer's guidelines for air gap size and placement.
The R-value of closed-cell foam is R-6.5-7 per inch. Contractors often use it to insulate under slabs, ceilings, walls, and roofs. It performs better than other insulation types. It provides an excellent air barrier, resists moisture, and retards vapor.
Closed-cell foam should generally be sprayed four to five inches thick for ceilings and roofing and two to three inches thick for wall insulation. Open-cell foam should be a few inches thicker, with six to ten inches for the ceiling or roof and at least three inches for walls.