Does Polyurethane Insulation Degrade?

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Many construction projects like to use polyurethane insulation because it is durable, cost-effective, and reduces heat loss. However, you may be wondering if polyurethane insulation degrades, and if so, after how long? We researched polyurethane and its expected longevity when used for various applications. Learn more about the advantages and nature of this popular insulation material.

When applied correctly, polyurethane insulation can last the lifetime of your home, easily surviving over 80 years before degrading. It is vital to cover up this type of insulation so that moisture and UV contacts will not initiate its breakdown. Polyurethane has a considerable shelf-life and R-value compared to fiberglass and other forms of insulation. 

Polyurethane insulation is a dependable choice for walls, roofs, and areas where heat loss needs to be controlled. Keep reading as we delve into the intricacies of polyurethane insulation and compare it to other insulation options.

A man spraying polyurethane foam insulation, Does Polyurethane Insulation Degrade?

All About Polyurethane Insulation

Polyurethane was created in the 1930s by William E. Hanford as a rubber replacement. Today, this substance is manufactured for various industrial applications, including spray foam insulation, either flexible and open-cell or rigid with a closed-cell structure. Polyurethane foam improves noise cancellation, maintains a comfortable indoor temperature, and is ideal for cold climates.

Foam insulation in between the wooden framing of the walls of a house

Polyurethane insulation, as with most polymers, is structurally hardy and does not degrade easily, unless exposed to moisture and light. Ideally, polyurethane insulation is suitable for foundation walls and large areas of a structure. But, you can apply it to doors, windows, and smaller areas as needed. Note, this type of insulation lasts decades, up to 80 years or more, if a home is properly maintained.

Many people like to use polyurethane insulation because it is resistant to mold and moisture, making a building more airtight. Also, this form of insulation has a stable structure, which does not readily shrink or change in response to fluctuating conditions.

It is advantageous to use polyurethane because it can be applied with a foam gun, and it adheres to most materials to create a waterproof barrier. You should hire a professional to install this insulation in your home.

Points To Consider

Watch out for gaps in insulation, replace old insulation, and fix leaks in the roof and plumbing to prevent the degradation of polyurethane insulation.

  • Over time, anywhere moisture and mold can develop also reduces the effectiveness of your home’s insulation and contributes to heat loss.
  • Modern insulation like polyurethane foam is less susceptible to damage from humidity and is mold-resistant.
  • Polyurethane insulation is more expensive than fiberglass, but it is excellent at reducing air and water leaks.
  • Choose insulation for its respective cell structure, density, cost, and R-value to retain thermal performance.

Signs Of Poor Insulation

It is not recommended to apply spray foam polyurethane as a DIY project. Improperly installed insulation, gaps or moist areas, heat, oxidation, and light can all contribute to poor thermal resistance and performance.

There are many types of polymer insulation, so be aware if it is better to choose an open-cell or closed-cell structure. Polyurethane insulation that is properly installed and in a well-maintained property should last for decades.

If you experience the following problems, you should review your insulation:

  • The walls and ceilings feel cold to the touch.
  • Energy bills are typically very high.
  • The temperature indoors is frequently inconsistent.
  • There are problems with pests and leaks present.

Polyurethane insulation should expand and adhere to most materials, including wood, concrete, plastics, and metal. When the insulation is correctly installed and cured, there shouldn’t be problems with heat loss, drafts, leaks, mold, and inconsistencies with the temperature indoors. Prevent your HVAC system from working harder than it should with a professional installation.

Is Polyurethane Foam Biodegradable?

Polyurethane is a hardy human-made material. However, even it can succumb to biodegrading thanks to microorganisms.

If polyurethane existed in an anaerobic environment, it could indefinitely continue to exist without breaking down. However, the polyurethane can survive for decades before moisture, UV light, and microorganisms contribute to its demise.

How Long Does Polyurethane Insulation Last?

For the most part, polyurethane insulation can last as little as 30 years or as much as 100 years under the right conditions. Note, this type of insulation is susceptible to breaking down if it is in contact with UV light, excessive moisture from leaks, or is in a poorly maintained abode.

Polyurethane is a popular choice of insulation because of its durability and resistance to mold and mildew. This is despite it being more expensive than other insulation.

How Long Does It Take For Polyurethane Foam To Decompose?

If you were curious about how long it takes for polyurethane foam to decompose, it takes as little as 20 to 30 years. Typically, exposure to light, moisture, and heat will cause the substance to crumble, lose its flexibility, and show discoloration. Contact with naturally occurring microorganisms will contribute to the decomposition of polyurethane foam over time.

Which Is Better Insulation, Polystyrene Or Polyurethane?

Polyurethane, hands down, is the better insulation compared to polystyrene. Although both human-made materials are polymers, the complexity of polyurethane makes it a more durable substance that has improved longevity.

Unlike polystyrene, polyurethane has a higher R-value or thermal resistance. It doesn’t melt until temperatures reach an extreme 700 degrees.

Polystyrene is not as resistant to chemicals as polyurethane, and it is more vulnerable to degrading very quickly following light and oxidation exposure. Polystyrene insulation comes in sheets, but polyurethane is applied via a spray foam gun. Although polyurethane is more expensive, it is preferred over polystyrene for many projects.

What Insulation Lasts The Longest?

A worker installing foam insulation on the inner walls of a house

There are various types of insulation used for properties that are designed for foundation walls, flooring, windows, roofs, ceilings, attics, and other spaces. However, each type of insulation relies on specific materials and has different lifespans. Under the best conditions where light and moisture are kept to a minimum, most insulation lasts for decades before needing to be replaced.

Insulation may be spray foam, rigid fibrous, a panel, loose fill-in, concrete, or a blanket roll style. Here are some common insulation types used and their lifespan:

  • Cellulose – lasts 20 to 30 years
  • Foam board (rigid) – lasts up to 100 years
  • Fiberglass – lasts between 80 to 100 years
  • Mineral wool – 80 to 100 years or longer
  • Polystyrene – 30 to 50 years
  • Polyurethane – 80 to 100 years
  • Straw core insulation – 100 years

Insulation longevity may vary based on its surrounding conditions. In some cases, insulation may fall away from its board, batting roll, or loosen from previously adhered surfaces over time.

What Does Bad Insulation Look Like?

Especially if you have purchased an older home, it is critical to check out the structure for poor insulation needing replacement. Leaking roofs, plumbing issues, pests, microorganisms, oxidation, and fluctuating temperatures can impact insulation performance. If you notice sky-high electric bills and inconsistent temperatures throughout your home, it’s time to review the insulation between the walls.

Poor insulation will show signs of discoloration, might be crumbling or shrunken, have lost elasticity, and reduced thermal retention. You may notice internal condensation, an increased presence of rodents and insects, or growing holes in the wall where there are gaps in insulation.

Immediately remedy insulation coated in mold, giving off foul odors, and letting in drafts. Bad insulation can contribute to an uncomfortable home with increasingly unsafe conditions if ice dams, mold, mildew, and pests are a frequent sight. Quality insulation should be suitable for the site where it is installed and last for decades without readily degrading in performance.

In Closing

We hope you learned some helpful information about polyurethane insulation and why it is an optimal choice for your home. It is critical that your property’s insulation protects against heat loss, resist mold, moisture, and creates an airtight seal. Address any areas of the home like leaks, gaps, old insulation that needs replacing, or structural integrity problems that can thwart the performance of your insulation.

When a home is properly maintained, polyurethane insulation can last for decades, well over 80 years. Because of the nature of polyurethane insulation and state laws, hire a certified professional to expertly install this type of insulation. For the most part, polyurethane insulation is one of the best types of insulation to wrap around your home. When correctly installed, this insulation eliminates drafts, keeps pests out, and inhibits the growth of mold and mildew.

Before you go, don’t skip out on the following helpful articles:

Read More: How Long Does Spray Foam Insulation Smell?

Read More: Can Foam Insulation Be Installed In Existing Walls?

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