Installation instructions: Manhole steps

How to install manhole steps in shafts correctly: Use our installation instructions with dimensions, distances, and tips for retrofitting in civil engineering.

Manhole steps are safety-related components in civil engineering. They enable maintenance and inspection personnel to enter and exit shafts safely. Proper installation is crucial: even slight deviations in drilling dimensions, embedding depth, or tool selection can impair load-bearing capacity.

Our installation instructions explain the function, installation specifications, distances, and tips for retrofitting.

What are manhole steps and what are they used for?

Manhole steps are access aids that are firmly anchored in the shaft wall. They form a permanently installed climbing aid and enable safe access to underground structures. Unlike mobile ladders, they are an integral part of the structure and must withstand both static and dynamic loads.

In municipal civil engineering, manhole steps are mainly used in sewage, rainwater, cable, and supply shafts. Since these structures are permanently exposed to moisture, chemical influences, and temperature fluctuations, corrosion protection and secure anchoring play a central role.

The quality of the product and the precision of the installation directly determine safety and lifespan.

Basics of manhole steps shaft installation

Before the actual installation begins, the structural requirements must be checked. The following minimum requirements must be met:

• Minimum wall thickness: 80 mm • Load-bearing substrate • Suitable drilling technique

Secure integration into the shaft wall can only be guaranteed if the wall thickness is sufficient.

Manhole steps shaft installation: How to install correctly

1. Drill holes

Two holes are drilled into the shaft wall for installation. The following dimensions must be observed:

• Horizontal hole spacing: 330 mm

• Drilling depth: 70 mm

• Drill diameter: 26 mm for concrete, 25 mm for softer building materials

Precise alignment is particularly important: The drill holes must be coaxial, symmetrical, and tension-free. Even slight dimensional deviations can impair the integration of the thread.

2. Clean and prepare the drill holes

After drilling, the holes must be thoroughly cleaned. Dust and drill residue must be completely removed to ensure optimum adhesion.

The tips of the manhole steps are then dipped in cement slurry. This improves the bond between the metal and the concrete and increases the durability of the anchorage.

3. Drive in the manhole steps

The manhole step is now driven into the prepared drill holes. It is particularly important to note the following:

• Only use a plastic hammer

• Do not use metal hammers

• Apply even, controlled blows

Metal hammers can damage the protective plastic coating and impair corrosion protection.

4. Check the anchoring

Installation is only complete when the 65 mm long spiral thread has disappeared completely into the shaft wall. Visible thread ribs mean:

• Incomplete integration

• Reduced holding force

• Increased safety risk

A final visual inspection is therefore essential.

Manhole Steps shaft distance and ergonomic climbing sequence

In addition to the horizontal hole spacing, the vertical arrangement also plays an important role. A uniform climbing sequence ensures ergonomic access and reduces the risk of accidents during maintenance work.

The horizontal spacing of 330 mm ensures a stable footing and even load distribution in the shaft wall. In combination with a professionally planned vertical arrangement, this creates a permanently resilient access system.

In the municipal sector in particular, the relevant technical regulations and local requirements must also be taken into account.

Retrofitting or replacing manhole steps in the shaft

As part of renovation measures or in the case of damaged components, it may be necessary to retrofit or replace manhole steps.

Replacing loose manhole steps

• Cut open the plastic coating close to the wall

• Pull out the manhole steps

• Drill out any plastic residue

• Apply mortar ≥ 40 MPa

• Insert the new manhole steps

Replacing manhole steps in dowel sleeves

• Loosen the manhole step with a defined force

• Pull out alternately on both sides

• Only use dowel sleeves that are compatible with the system

Combining incompatible components can compromise safety.

Replacement in pre-drilled holes

• Remove old bracket

• Apply mortar

• Drive in new bracket correctly

• Check that it is fully anchored

Avoiding typical mistakes when installing manhole steps

In practice, similar mistakes occur time and again during manhole steps shaft installation, but these can be reliably avoided with careful execution.

• If the wrong drill diameter is selected, the manhole step either cannot be anchored securely or it sits under tension in the shaft wall, which has a negative impact on load-bearing capacity and durability.

• If the specified drilling depth is not adhered to, the spiral thread cannot develop its full binding effect, which means that the holding force specified in the design is not achieved.

• If the drill holes are not thoroughly cleaned before inserting the manhole steps, dust and residues will impair the bond between the cement slurry, thread, and concrete.

• If a metal hammer is used for driving, the plastic coating may be damaged, interrupting the corrosion protection and reducing the service life of the component.

• If the 65 mm long spiral thread is still visible after installation, the manhole steps has not been completely sunk and the required load-bearing capacity is not guaranteed.

• If non-system-compliant dowel sleeves or unsuitable mortar are used for retrofitting, the structural safety of the entire access system cannot be reliably guaranteed.

Consistent implementation of the installation instructions and careful checking of all dimensions and assembly specifications ensure that the entry system remains durable and reliable in operation.

Advantages of Infrastep manhole steps

Infrastep manhole steps are designed to meet the requirements of civil engineering and combine secure anchoring with durable construction.

Permanent corrosion protection

The resistant plastic coating reliably protects the component from moisture, chemical influences, and mechanical stress, thus increasing its service life in shaft operation.

High holding force

The 65 mm long spiral thread enables a force-fit connection to the shaft wall and ensures stable anchoring even under repeated stress.

Can be used in new construction and retrofitting

The system is suitable for both new shaft structures and for retrofitting existing systems, enabling a uniform solution across different project phases.

Replacement of individual manhole steps

Damaged or worn manhole steps can be replaced individually without having to replace the entire shaft component.

Cost-effective solution

The durable design and modular interchangeability result in lower maintenance costs and greater planning reliability for operators and construction companies.

Lasting safety begins with installation

If you want to install manhole steps in a shaft, you should precisely coordinate the drill diameter, embedding depth, and system components. This is the only way to ensure that the climbing technology in the shaft is permanently resilient and reliable.

Precise implementation of the installation instructions not only ensures safety, but also reduces subsequent maintenance and renovation costs.

Are you planning a new construction or renovation project in civil engineering? We can help you select suitable manhole step systems and advise you on a technically and economically suitable solution.