Insulation values of Plexiglas: What you need to know

Plexiglass, also known as acrylic glass or PMMA (polymethyl methacrylate), is a widely used material in the construction and interior design industries. Although it is often chosen for its transparency and impact resistance, plexiglass also has insulating properties that can be important when designing windows, partitions and other applications. In this blog, we discuss what you need to know about the insulation values of plexiglass and where the material is best used.

What Is Thermal Insulation?

Thermal insulation refers to the ability of a material to delay heat transfer. This is often expressed as a U-value (W/m²K), with a lower U-value indicating a better insulation value. The lower the U-value, the less heat is lost through the material, resulting in better thermal efficiency.

Insulation values of Plexiglas

Plexiglass has naturally good insulating properties compared to glass. The U-value of standard single plexiglass is around 5.0 W/m²K, while single glass has a U-value of about 5.8 W/m²K has. This means that plexiglass already insulates slightly better than traditional glass. With double plexiglass layers or in combination with other insulating materials, the insulation value can be further improved.

Here is an overview of insulation values for different plexiglass applications:

1. Single Plexiglass: approx. 5.0 W/m²K
2. Double Plexiglass: approx. 2.8 - 3.5 W/m²K
3. Plexiglas with coating: Plexiglas can be provided with a special insulating coating to further reduce heat loss. The exact U-value depends on the type of coating and the thickness of the material.

Comparison with Traditional Glass

To get a good idea of the insulation value of plexiglass, it is useful to compare it with glass:

• Single glazingU-value of 5.8 W/m²K
• Double glazingU-value of approx. 2.8 W/m²K
• High-efficiency glass (HR++ glass)U-value of approx. 1.1 - 1.3 W/m²K

Although plexiglass insulates better than single glass, it does not yet quite match high-efficiency glass in terms of insulation value. This makes plexiglass a good choice for applications where insulation is important, but not necessarily at the level of HR++ glass.

Applications of Plexiglass for Insulation Purposes

Plexiglass is particularly suitable for certain insulation applications where the focus is on lightweight, safety, and impact resistance. Here are some examples of how plexiglass can be used for insulation:

1. Partitions and interior spaces: Plexiglass can be an effective insulation solution for indoor spaces. It provides protection against draughts and helps better regulate the temperature within a room, especially in larger, open spaces where energy efficiency is a factor.
2. Conservatories and patio covers: Plexiglass is often used in conservatories and patio covers because it lets in a lot of light and insulates better than single glass. This keeps the room warmer for longer, especially when combined with heating systems.
3. Insulation panels and glazing for furniture: For furniture and cabinets that require a transparent look, Plexiglas offers a thermally insulating solution that is translucent and impact-resistant.
4. Sound insulation: Although Plexiglas is best known for thermal insulation, it also has sound insulation benefits. It can absorb sound vibrations and is useful in offices and studios, for example, where noise pollution is a problem.

Advantages of Plexiglas as insulation material

• Lightweight and impact-resistant: Plexiglass is about half as light as glass and much more impact-resistant, making it safer in applications such as doors and windows.
• UV resistance: Plexiglas has a natural resistance to UV radiation and discolours less quickly than other plastic materials, ensuring a longer lifespan.
• Light transmission: The material allows up to 92% of light through, similar to glass, creating bright, well-lit rooms without much heat loss.

Disadvantages of Plexiglas as insulation material

Although plexiglass offers advantages for thermal insulation, there are some limitations:

• Lower insulation value than HR glass: If you are looking for the highest level of thermal insulation, HR++ glass is a better option.
• Scratch sensitivity: Plexiglass is more susceptible to scratching than glass, making it less suitable for outdoor areas or places of heavy use.

Conclusion

Plexiglass offers a good balance between insulation, light transmission and impact resistance, and is an attractive alternative to traditional glass in specific applications. Although the insulation value is not as high as that of high-efficiency glass, the advantages of weight, strength and light transmission are sometimes decisive, especially in indoor spaces and conservatories.

If you are considering plexiglass for insulation purposes, look at the required insulation value, area of application and cost to make the best choice. Due to the versatility of plexiglass, there is almost always a solution that suits your needs and design!