Electrical boxes are an essential component in every electrical wiring installation. These boxes serve as a protective covering for wires and connections, ensuring safety and longevity. When choosing the suitable material for your electrical box, two options often come into consideration – fiberglass and plastic.

Due to the longevity, affordability and ease of installation, fiberglass and plastic have become a popular choice. However, they are characterised by specific characteristics that allow them to be used for various applications.

Fiberglass Electrical Boxes

 Fiberglass, or glass-reinforced plastic grip, is a lightweight and durable material combining glass fibres with polyester resins. This results in a versatile material that can be moulded into various shapes and sizes. 

Plastic Electrical Boxes

Plastic electrical boxes are made from various materials, such as PVC, polycarbonate, and ABS (acrylonitrile butadiene styrene). These materials are lightweight, durable, and resistant to corrosion.

Pros and Cons of Fiberglass Electrical Boxes 

Pros:

• Excellent strength-to-weight ratio: Fiberglass has high tensile strength and is incredibly strong. This makes it ideal for outdoor installations where the box may be subjected to harsh weather conditions.
• Corrosion resistance: Fiberglass is non-metallic, making it resistant to corrosion caused by moisture or chemicals. This feature makes fiberglass boxes suitable for damp locations such as bathrooms and kitchens.
• Fire resistance: As a non-conductive material, fiberglass is highly resistant to fire and can withstand high temperatures without melting or deforming.
• UV resistance: Fiberglass is also resistant to ultraviolet (UV) rays, which can cause other materials, such as plastic, to degrade when exposed to sunlight.

Cons:

• Fiberglass can become brittle over time if not adequately protected despite its strength. This makes it unsuitable for frequent handling or heavy objects placed on top of it.
• Cost: Fiberglass boxes are more expensive than plastic, making them less popular among budget-conscious consumers. 

Pros and Cons of Plastic Electrical Boxes

Pros:

• Cost-effective: Plastic boxes are generally more affordable than fiberglass boxes, making them popular for most residential and commercial installations.
• Lightweight: Compared to fibreglass, plastic is much lighter and easier to handle during installation. It’s also a good choice for making your DIY projects.
• Versatility:  Depending upon the shape and size, it may be easily formed to various sizes appropriate for different applications.

Cons:

• Lower strength: Despite being durable, plastic is less intense than fiberglass. This makes it vulnerable to cracking or breaking if subjected to heavy loads or impacts.
• Prone to UV damage: Unlike fiberglass, plastic is not resistant to UV rays and can degrade when exposed to sunlight. This can result in discolouration, cracking, and weakening of the box.

Conclusion

There is no clear winner when choosing between fiberglass and plastic electrical boxes, as both materials have unique strengths and weaknesses. Fibreglass may be the way to go if you want a durable and fire-resistant option. However, plastics may be a better choice if you’re on a budget and must ensure they are lightweight and flexible.

Before you decide, weighing up your particular needs and the purpose for which this device should be used is essential. Whichever material you choose, always ensure that it meets safety standards and is installed correctly for optimal performance. So, take your time to weigh the pros and cons before making your final decision.