How to Ensure That You Have a Fully Weatherproof Electrical Box

This blog aims to provide a comprehensive guide to achieving fully weatherproof electrical enclosures. These enclosures are crucial for safeguarding your electrical equipment from the elements.

We understand the importance of your electrical enclosures staying entirely weatherproof, so we aim to provide all of the necessary information for you to choose and maintain a completely waterproof and weatherproof enclosure for your electrics to be stored.

Frozen and covered with icicles fuse box installed outside on the wall of a building

Why is it so important that your outdoor electrical enclosures stay weatherproof


Maintaining the weatherproof integrity of outdoor electrical enclosures is of paramount importance.

Firstly, weatherproof enclosures prevent water and moisture from entering. This reduces the risk of short circuits, electrical malfunctions, and potential electrical shock hazards.

Exposure to the elements can also cause corrosion, condensation, and damage to electrical components. Weatherproof enclosures protect vital equipment, providing safety and ease of mind. 

Also, regular maintenance and replacement of damaged equipment due to weather exposure can be costly. It is therefore essential that your electrical enclosures are weatherproof, to save a lot of money in the long run.

A polyester, floor standing electrical enclosure

How to check that your weatherproof electrical enclosures are doing their job

By following these steps, you can be confident that your weatherproof electrical enclosures are protecting your electrical equipment:

  1. Inspect the enclosures for signs of damage, wear, or any breaches in the sealing mechanisms. Look for cracks, gaps, or loose fasteners that could compromise the enclosure’s integrity.
  2. Check the IP (Ingress Protection) rating of your enclosure. Ensure that it matches the environmental conditions that it is exposed to. Higher IP ratings provide better protection against dust and water.
  3. Examine the seals and gaskets, ensuring they are in good condition. Replace any damaged or worn seals promptly.
  4. Ensure that all ventilation components are unblocked and functioning correctly to prevent condensation buildup. Verify that drainage systems are clear to prevent water accumulation inside the enclosure.
  5. Inspect cable entry points and ensure they are properly sealed with cable glands or conduit fittings to prevent water ingress along wires and conduits.
  6. Ensure that all fasteners, hinges, and locking mechanisms are securely in place to maintain the enclosure’s structural integrity.

What is the science behind waterproof electrical junction boxes keeping all water out?

Waterproof electrical junction boxes rely on a combination of design and materials to prevent water from entering and damaging electrical components, these include:

  • Sealing. These boxes should have tight seals, typically made of rubber or silicone gaskets, that encircle the enclosure’s edges. These seals create a watertight barrier that prevents water from seeping inside.
  • Enclosure Material. Waterproof junction boxes are often made from non-porous and water-resistant materials, such as plastics, metals, or fiberglass. These materials do not absorb water and can withstand exposure to moisture without degrading.
  • Cable Entry Points. These boxes include carefully designed cable entry points that are fitted with sealing mechanisms to prevent water from entering through wires and conduits.
  • Ingress Protection (IP) Ratings. IP ratings are standardised measures that indicate an enclosure’s level of protection against solid particles and water. Higher IP ratings, like IP67 or IP68, provide a higher degree of water resistance.
IP66, IP67 and IP68 Waterproof rating, water protective capability. Water and dust protection, water resistance level icon and symbol.

What is the best material choice for a weatherproof electrical box?


The best material choice for a weatherproof electrical box depends on your different requirements. 

Polyester electrical enclosures

Polyester electrical boxes are corrosion-resistant, making them ideal for outdoor applications. They offer good chemical resistance and UV stability, making them suitable for harsh weather conditions. Polyester is also lightweight and easy to install.


Stainless Steel electrical enclosures

Stainless steel provides excellent corrosion resistance, making it a top choice for outdoor enclosures in marine or highly corrosive environments. It is durable and can withstand extreme temperatures, making it a reliable option for long-term use.


Mild Steel electrical enclosures

Mild steel is a cost-effective option. It offers robust structural support and can withstand mechanical impact. However, it requires regular maintenance and coatings to prevent corrosion in outdoor settings.


Glass Reinforced Plastic electrical enclosures

GRP enclosures are lightweight, highly corrosion-resistant, and electrically non-conductive. They are suitable for use in harsh industrial environments and are UV-stable.


ABS Plastic electrical enclosures

ABS plastic is a durable and cost-effective material that provides good impact resistance. It is often used in less demanding outdoor applications and is known for its electrical insulation properties.


Polycarbonate electrical enclosures

Polycarbonate is a lightweight and durable material known for its high impact resistance. It offers excellent UV stability and is often used in outdoor electrical enclosures, especially when the visibility of the equipment inside is important.

Five different polyester enclosures

What is the best type of plastic weatherproof electrical enclosure?


The choice of the best plastic weatherproof electrical enclosure can depend on temperature fluctuations, UV exposure, and the level of protection required. 

Polycarbonate and polyester are often preferred for extreme weather conditions, while ABS and GRP can be suitable for less demanding outdoor settings.

Polycarbonate is known for its excellent weatherproof properties. It offers high resistance to UV radiation, making it ideal for outdoor use. It also maintains its structural integrity in a wide range of temperatures and provides good protection against moisture, dust, and corrosive elements.

ABS plastic provides reasonable weatherproofing, making it suitable for less extreme outdoor conditions. While not as UV-stable as polycarbonate, ABS is still resistant to moisture and offers adequate protection against dust and small debris.

GRP enclosures are highly weatherproof. They offer excellent resistance to moisture and corrosion, making them suitable for harsh outdoor environments. GRP also maintains its structural integrity under UV exposure.

Polyester enclosures are known for their exceptional weatherproofing. They resist moisture and corrosion and maintain their integrity even in extreme weather conditions. They offer reliable protection against UV radiation.

High-quality IP67 electrical enclosures in grey

Choose your weatherproof electrical box today!

With a wide range of weatherproof materials to choose from, and over 25 years of experience in the industry, we have the highest quality electrical enclosures that are expertly designed to be weatherproof. 

Our comprehensive range of enclosures are available on a next day delivery service anywhere in the UK. Get in touch with us today for a free quote online!

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