Manhole covers might seem like a small detail, but they play a crucial role in safety, functionality, and aesthetics around your home or site. Here’s a quick guide to help you select the right one for your needs.
1. What are the durability options of covers? Load Classes and Usage
Manhole covers are classified based on how much load they can bear, as per the EN 124 standard. For areas with pedestrian or light vehicle traffic, covers rated A15 (15kN) to B125 (125kN) are sufficient. However, D400 is the most commonly used class, designed to withstand up to 400kN, making it ideal for driveways or roads. It’s also widely available, making it easier to find spares when needed.
2. What do I need to consider regarding safety? Lockable vs. Non-Lockable Covers
Safety is an important consideration, especially in areas where children play. Non-lockable manhole covers are held down by their weight, but theoretically, they can be pried open. Lockable covers in our markets, on the other hand, use a spring mechanism, providing additional security. However, even these can be opened with some effort, so while they offer more protection, they are not foolproof.
3. When do I use a solid cover or grating?
The type of cover you need depends on its function. Grated covers allow rainwater to flow through, which makes them suitable for drainage systems. Solid covers are meant for inspection chambers that provide access to utilities like sewage or rainwater lines or underground cables.
4. What size should the cover then be? Sizing and form
The size of the manhole cover is critical for proper fitting. It’s important to measure the clear opening (the inside dimension of the frame) to ensure the cover fits securely. Common circular covers come in sizes like 300mm or 600mm in diameter, while square and rectangular covers follow standard dimensions. The most common telescopic pipes to which the frames are installed in residential areas are in 160mm, 315mm or 500mm with some national variations.
5. How should the frame be installed? Support and Installation Requirements
A proper installation includes ensuring sufficient support beneath the frame. This is typically done using gravel, concrete, or another locally appropriate material. The support helps distribute the weight and ensures the cover doesn’t shift or sink under the load of passing vehicles.
6. But what about the looks of your cover? Normal Iron Cover or Design Cover?
While functional covers get the job done, you might want something that adds a bit of personality to your property. Combi Works also offers design covers created by renowned Finnish designer Piia Keto, known for her collaborations with brands like Marimekko and her designs for the Finnish National Library Oodi. These design covers combine functionality with beauty, making them a unique addition to your landscape. You can check out some of the available designs here for inspiration.
With these key points in mind, you can select a manhole cover that balances practicality and style for your home or site. The full range of manhole covers for our markets in Finland, Estonia, Sweden and other countries here.
