What Is the Best Type of Insulation? A Comprehensive Comparison

Insulation plays a pivotal role in modern construction, affecting how comfortable our spaces are and how energy-efficient our buildings become. 

Making the right choice is vital, as using the wrong insulation can lead to a range of issues, including compromised energy efficiency, poor indoor air quality, increased costs, and even health hazards for occupants. With so many insulation choices available, picking the best one might feel overwhelming. 

This guide is here to help make that decision easier. We’ll explore different insulation types, with a focus on expanded polystyrene (EPS) insulation — a versatile option that’s perfect for designers, builders, and homeowners.

Key Factors in Selecting the Best Insulation Type

Whether you are constructing a new residential space, commercial complex, or industrial facility, one thing is clear: You want it to be efficient, comfortable, and environmentally responsible.

At the heart of your building lies insulation, a versatile element with applications ranging from rooftops to below-grade installations. But how do you determine which insulation solution is the right fit for your project?

Before choosing, you should know exactly what you expect each insulation material to do. First, let’s break down the key factors that are important for you to make an informed decision:

• Published R-value vs actual R-value: Understanding the difference between published and actual R-values is crucial. Manufacturers may claim high R-values, but real-world conditions can influence thermal performance, and they actually decrease fairly rapidly when in use.
• Thermal stability: Different insulation materials react differently to temperature changes. Consider how each material maintains its thermal stability across various conditions.
• Moisture/water resistance: Effective installation and preemptive moisture management are crucial to uphold the moisture resistance of insulation materials. Leveraging vapor barriers and best practices can increase the overall moisture performance of an insulation system.
• Vapor/air resistance: Proper installation practices and consideration of vapor barriers are essential for achieving effective vapor and air resistance in insulation systems. Your insulation choice should align with the project’s specific requirements and local climate conditions.
• Fire performance: The fire performance of insulation materials can be influenced by factors such as additives, facers, and specific product formulations. Building codes and regulations also play a significant role in determining acceptable fire performance for various applications. When selecting insulation for a specific project, it’s important to consider local codes and standards to ensure compliance and safety.
• Insect resistance: While some insulation materials have inherent insect resistance due to their composition, proper installation practices and additional treatments can play a key role in preventing insect infestations. Understanding local pest pressures and building practices when selecting insulation ensures effective protection against pests.
• Sound control: The sound control performance of insulation materials can be influenced by factors such as density, thickness, and specific application. For optimal soundproofing, it’s important to consider specialized soundproofing materials and construction techniques in addition to insulation.
• Sustainability: When assessing the sustainability of insulation materials, factors such as resource use, manufacturing processes, embodied energy, recyclability, and environmental impact should be considered. Additionally, the availability of local recycling programs and waste management practices can impact the sustainability of different insulation options.
• Compatibility with roofing and other building materials: Smooth integration with roofing and building materials is indispensable for effective installation and performance. Adhering to manufacturer guidelines and consulting building experts guarantees the synergy of chosen materials and systems within the project.
• Ability to be tapered and shaped: The capability for custom tapering and shaping is a design-defining feature. While some insulation materials offer enhanced flexibility, proper installation expertise is pivotal to achieving desired outcomes.
• Open or closed cell: Choosing between “open-cell” and “closed-cell” cellular structures impacts breathability, acoustic performance, R-values, and water resistance. Understand the differences to make the right decision.
• Cost: While upfront costs are an important consideration, it’s equally crucial to factor in long-term savings from improved energy efficiency and potential benefits such as enhanced comfort and reduced utility bills. Additionally, the specific costs for each insulation type can vary based on the manufacturer, local availability, and regional pricing trends. It’s recommended to obtain quotes to get accurate cost estimates for your project.

Evaluating Common Types of Insulation

Let’s take a closer look at the different types of popular insulations.

Expanded Polystyrene (EPS) Insulation

EPS insulation, also known as beadboard or foam board, is a versatile and widely used option in the construction industry. It’s known for its exceptional thermal insulation properties, making it effective in minimizing heat transfer and reducing energy consumption. EPS insulation is lightweight, easy to handle, and offers good moisture resistance.

Advantages

• Excellent thermal insulation
• Lightweight and easy to install
• High resistance to moisture and water absorption
• Cost-effective
• Versatile application for the entire building envelope
• Ability to upgrade to graphite polystyrene (GPS) for a 20% increase in R-value to R-5
• Fire-resistant with proper treatment (R-Shield incorporates this in the manufacturing process)

Considerations

• Lower R-value compared to some options, but does not decrease/is stable over time
• Susceptible to sun damage (requires proper protection)
• Requires proper vapor barrier in certain applications

Extruded Polystyrene (XPS) Insulation

XPS insulation, a rigid foam variant, excels in moisture resistance, making it suitable for areas prone to water exposure and below-grade applications. Its closed-cell structure contributes to enhanced water resistance and thermal performance.

Advantages

• High moisture resistance
• Strong vapor and air resistance
• Stable and consistent thermal resistance
• Durable and long-lasting

Considerations

• Higher cost compared to EPS
• Hydrofluorocarbon (HFCs) are off-gassed, making them damaging to the environment and causing the product to lose some insulation performance over time
• Heavier weight, which can make it more difficult to handle and install
• In below-grade applications, retains moisture over time reducing R-value
• Limited environmental friendliness due to the manufacturing process

Polyisocyanurate (Polyiso) Insulation

Polyiso insulation offers versatility with its high R-value, proving effective in providing thermal resistance within relatively thin panels. Common in commercial and residential applications, it often features a foil facing acting as a radiant barrier.

Advantages

• High R-value per inch of thickness out of the factory
• Effective in most climates
• Excellent vapor and air resistance
• May include reflective foil facing for radiant heat control

Considerations

• Higher cost compared to many other insulation types
• Vulnerable to sun damage
• Susceptible to moisture absorption, affecting R-value
• Does not perform well in cold temperatures

Fiberglass Insulation

Fiberglass insulation is a well-recognized, budget-friendly option. Comprising glass fibers, it is available in batts and loose-fill forms. While relatively easy to install, its thermal performance depends on proper installation.

Advantages

• Cost-effective
• Naturally non-combustible
• Available in various forms

Considerations

• Susceptible to moisture retention, impacting performance
• Prone to mold growth due to moisture
• Settling over time reduces its effectiveness
• Can melt and lose its shape when exposed to high temperatures
• Can be irritating to the skin, eyes, and respiratory system during installation
• Installation can be messy if not done correctly

Cellulose Insulation

Cellulose insulation is an environmentally friendly option made from recycled paper and treated to be fire-resistant. It’s often used as loose-fill insulation and is blown into wall cavities or attics. Cellulose insulation is effective in reducing air leakage and providing good thermal performance.

Advantages

• Made from recycled materials
• Effective at reducing air leakage
• Good thermal performance
• Fire-resistant with proper treatment

Considerations

• May settle over time, requiring occasional topping off
• Dissipates over time, creating airborne contaminates
• Installation requires special equipment and expertise
• Contains artificial chemicals

Mineral Wool Insulation

Mineral wool, also known as rock wool or slag wool, is made from natural minerals and offers both thermal and sound insulation. It’s available in various forms, including batts and rigid boards. Mineral wool is known for its excellent fire resistance and provides good acoustic insulation.

Advantages

• Stable R-value
• Fire-resistant and non-combustible
• Excellent sound insulation properties
• Resistant to mold and pests
• Durable and long-lasting

Considerations

• Higher costs than some alternatives
• Heavier and denser, which can affect installation ease

Elevate Your Construction Projects With R-Shield EPS Insulation

With an affordable price and environmental advantages, there is no better time than now to explore the benefits of EPS insulation. There is simply no other insulation product that offers the versatility, flexibility, and control needed in one product offering.

Whether you’re revitalizing an existing structure or envisioning a low-energy new construction, R-Shield rigid insulation stands ready to meet your project’s demands without straining your budget. This versatile insulation offers adaptability, sustainability, and impressive thermal performance.

R-Shield redefines construction standards by seamlessly meeting rigid insulation demands across various applications. As part of Premier Building Systems and a legacy dating back to the 1950s, R-Shield ensures quality and reliability. Backed by a sturdy 50-year warranty, R-Shield reflects a commitment to your project’s success. 

Get an estimate today — our team of insulation experts is ready to assist you with your project needs, estimate requests, and product information.