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Will Spray Foam Really Rot Your Roof?

There have been so many arguments and debates on whether spray foam rots away the roof. Even more confusing is the fact that the argument is being supported and disputed by well-respected and learned professionals. Before going deep into this burning question, it is important to quickly differentiate between the types of Spray Foam available.

There are two types of spray foam, the first is the open-cell spray foam insulation while the second is the closed-cell spray foam. Each of the them has its own advantages and disadvantages which plays a major part on their effectiveness at different parts of the world.

The advantages of the open-cell spray foam lie in its low cost of installation, plus, is very easy to install. However, its disadvantages lie in its low effectiveness in the cold climates due to its inability to be used during low temperature associated with the cold climates.

The closed-cell foam spray, on the other hand, can be used anywhere due to its effectiveness in times of low temperature. The major drawbacks of the closed cell are that: it is very expensive to install; difficulty in installation and; high material usage.

Therefore, unless the complaints about spray foam leading to the rotting of the roofs is analyzed objectively and without bias, one may not be able to really ascertain whether spray foam can lead to the rotting of the roof.

Taking a closer look at the bunch of complaints about the rotting of the roof as a result of Spray Foam will show that the rotting of the roof as a result of Spray Foam is not universal and is subjective, in fact, the issue seems to be a climatic one in nature.

As a result of the fact that indoor moisture can diffuse through the foam and get access to the roof sheathings leading to the rotting of the roof, open-cell spray foam is not advisable in cold climates. This is due to its low water vapor permeability. Therefore, higher density closed-cell spray foam is the preferred method amongst majority of qualified professionals in the cold climates of the world.

Some have even argued that in cold climates, installation of a water retarder ensures that open-cell spray foam can be utilized. Also, the improper installation of close-cell spray foam in the cold climates can lead to water permeating the foam and its consequent rotting of the roof.

However, the open-cell spray foam is widely accepted in the warmer and equatorial climates of the world because precipitation is not common like it is in the colder climates.

Therefore, it should be noted that spray foam can lead to rotting of the roof if it is not effectively done. It is advisable to use close-cell spray foam in the cold climates but if open-cell spray foam must be used then the following should be followed:

  • Do not use open-cell spray foam unless you are using a water vapor retarder.
  • Ensure you hire a professional who will install it as building codes demand.

The notion that spray foam can lead to the rotting of the roof is wrong as there is no way the effective installation of spray foam can rot the roof, check out Insulation Wizards for more information on Insulation.