What’s the Difference Between Plastic and Metal Leveling Shims?

Leveling shims are essential tools used in construction, woodworking, and various other industries to create a stable and even surface when things are slightly off-balance. Whether you're leveling a door frame, a countertop, or a piece of heavy equipment, shims are a go-to solution. But when it comes to choosing the right type of shim for the job, the material plays a crucial role. Two of the most common materials used for shims are plastic and metal, and while they might seem similar at first glance, they each come with their own set of benefits and limitations. In this article, we’ll dive deep into the differences between plastic and metal leveling shims, helping you make an informed decision based on your needs.

Understanding Leveling Shims

Before we compare the materials, it’s important to understand the function of leveling shims. These small but vital pieces are used to adjust the height or level of an object or surface. They can be inserted between a surface and the object being leveled to compensate for height discrepancies, ensuring everything stays stable. Leveling shims can be made from various materials, with plastic and metal being the most commonly used.

What Are Plastic Leveling Shims?

Plastic leveling shims are made from high-density plastic materials designed to provide a lightweight, durable solution for leveling. These shims are versatile and often come in various shapes, sizes, and thicknesses to accommodate different needs. Plastic shims are typically used in applications where weight is a concern or when the material of the object being leveled might be sensitive to corrosion or staining.

One of the most significant advantages of plastic shims is their resistance to moisture and corrosion. Unlike metal, plastic doesn’t rust or degrade when exposed to water or chemicals. This makes plastic shims ideal for environments where moisture is a constant concern, such as in bathrooms, kitchens, or outdoor areas. Furthermore, plastic shims are non-reactive, meaning they won’t interact with or damage the materials around them.

What Are Metal Leveling Shims?

Metal leveling shims, on the other hand, are typically made from materials such as steel, aluminum, or brass. These shims are known for their strength and stability, providing a much firmer and more rigid leveling solution compared to plastic. Metal shims are usually preferred in industrial or heavy-duty applications where the load requirements are higher, or the object being leveled is heavy or requires extra support.

The main benefit of metal shims lies in their sheer strength and durability. They are resistant to wear and tear, can withstand heavy loads, and won’t deform easily under pressure. Metal shims are ideal for applications that require a high degree of precision or involve significant weight, such as in machinery, vehicles, or large equipment.

Key Differences Between Plastic and Metal Leveling Shims

Strength and Durability

One of the most significant differences between plastic and metal leveling shims is their strength. Metal shims are much stronger than plastic ones, making them better suited for heavy-duty applications. Whether you’re leveling a large machine or stabilizing a massive piece of equipment, metal shims can handle the weight without compromising their integrity.

Plastic shims, while durable in their own right, are generally better suited for lighter applications. They are often used in situations where the load is relatively small, such as furniture, doors, or small appliances.

Resistance to Elements

Another important factor to consider is how each material reacts to external elements. Plastic shims excel in environments where moisture or chemicals might be present. They won’t rust, corrode, or degrade, which makes them ideal for use in areas with high humidity or exposure to liquids. Plastic is also a non-conductive material, which can be an advantage in electrical environments.

Metal shims, while strong, are susceptible to rust and corrosion when exposed to moisture over time. However, certain types of metal, such as stainless steel or galvanized steel, are resistant to corrosion and can be used in harsh environments. Still, metal shims tend to require more maintenance in outdoor or wet conditions.

Weight and Ease of Use

Plastic shims are lightweight and easy to handle, making them an excellent choice when you need to move or adjust the shims frequently. They are easy to cut and modify, allowing you to create custom fits for specific applications. This ease of use is especially helpful for DIYers and non-professional installers.

In contrast, metal shims are heavier and more rigid, making them a bit more challenging to work with. While they are more stable under heavy loads, they can be harder to modify once they’ve been cut or shaped. Metal shims often require more precise tools for installation, which might not be ideal for less experienced users.

Cost Considerations

Cost is another significant difference between plastic and metal shims. In general, plastic shims tend to be more affordable than metal ones. Their lower cost makes them an attractive option for projects where budget is a concern or when you need to use a large number of shims.

Metal shims are usually more expensive, especially if you are working with high-quality metals such as stainless steel or brass. However, the added strength and durability they offer may justify the higher cost, especially in industrial or high-load applications.

When to Use Plastic Leveling Shims

Plastic leveling shims are best used in light-duty applications or when moisture resistance is crucial. They are an excellent option for leveling furniture, doors, windows, and other lightweight items. Plastic shims are also ideal for areas where corrosion is a concern, such as in outdoor settings or areas exposed to chemicals and water.

Additionally, plastic shims are great for situations that require frequent adjustments or custom sizing. They are easy to cut to fit specific spaces and can be used in a variety of different projects, including those that involve delicate or sensitive materials.

When to Use Metal Leveling Shims

Metal leveling shims are perfect for heavy-duty applications where strength and durability are the top priorities. If you're working with large machines, equipment, or structures that require significant support, metal shims are your best option. Their superior load-bearing capabilities ensure that they won’t buckle or bend under pressure.

If you’re working in environments where precision is critical, such as in the automotive or industrial sectors, metal shims offer the rigidity and stability you need for precise leveling. They are also a good choice for applications that require long-term durability and resistance to wear, such as leveling large machinery that will be subjected to heavy use.

Conclusion

Choosing between plastic and metal leveling shims depends largely on the specific needs of your project. If you’re working with lightweight items or in environments where moisture resistance is essential, plastic shims provide a great solution. They are affordable, versatile, and easy to work with. On the other hand, if you need a shim for heavy-duty applications or require a high level of precision, metal shims offer unmatched strength and stability. ​Certified Material Testing Products (Certified MTP) is a leading supplier of construction materials testing equipment and laboratory supplies in the United States. They offer a comprehensive range of products for testing concrete, asphalt, aggregate, soil, and cement, catering to both field and laboratory applications

Ultimately, understanding the strengths and limitations of both types of shims will help you make the right choice for your project. Whether you’re a DIY enthusiast or a professional, knowing the difference between plastic and metal leveling shims ensures that you select the best material for the job, leading to a more successful and efficient outcome.