Safe installation and maintenance, with the right skylight fall protection

The widespread diffusion of PV systems on commercial and industrial roofs has brought a complex technical issue back into focus: the risk of falling through non-load bearing skylights during PV panel installation and maintenance. Many existing buildings effectively incorporate skylights within trapezoidal metal roofs or sandwich panels. These elements provide natural lighting and contribute to the building’s energy performance, but are not designed to support the weight of a person. During work at height – such as PV module installation, inspections or routine maintenance – the risk of breakthrough is one of the primary hazards.

The topic has consequently attracted much technical debate, particularly in relation to permanent skylight fall protection systems installed directly over the skylight. In this scenario, safety design cannot be limited to simply “covering” the problem. It must be incorporated into the building while preserving its performance and compliance.

Is "boxing in" the skylight (really) the solution?

The practice of converting each skylight into a boxed structure, fitted with metal mesh or an additional frame, is intended to prevent falls through the opening. However, this solution presents a number of technical drawbacks:

• the absence of recognised product standards or specific certification schemes;

• the risk of unsealed penetrations and, consequently, water ingress;

• the potential invalidation of the assembly's non-fragility classification (ACR[M]001 test);

• reduced light transmission (estimated between 6% and 14% or more);

• the introduction of additional loads and potential trip hazards;

• greater complexity in inspection, cleaning and skylight replacement.

To address these issues, the alternative is not to intervene directly on the fragile element, but rather on the walking surface itself. This is the approach underpinning the OVERNET system.

OVERNET and permanent collective safety measures above the roof

OVERNET is a permanent industrial skylight fall protection system designed to safeguard workers on the roof surface rather than converting each skylight into a covered element. Suitable for installation on trapezoidal metal roofs or sandwich panels, OVERNET is supplied in 25 m rolls and creates a collective protection layer over the walking area in correspondence with non-load bearing skylights. The system is supplied complete with mesh, dedicated fastening plates, EPDM gaskets and rivets. This configuration ensures consistent, controlled installation, eliminating the need for generic fencing components or fastenings not designed for industrial roofing applications. The use of dedicated plates and EPDM gaskets helps to:

• avoid direct drilling into the skylights;

• comply with roofing manufacturers' guidelines;

• preserve warranties;

• maintain the assembly's non-fragility classification.

Compliance, durability and lightness

OVERNET undergoes extensive testing, documented by an independent third party in a dedicated technical dossier. This is particularly relevant at the design and risk management stages, especially in a mature market such as the UK. The surface protection system – consisting of galvanising, primer and PVC coating – ensures long-term durability, avoiding the use of materials less resistant than the skylights themselves.

Another issue associated with boxed skylight enclosures is the introduction of additional loads onto the roof structure. By contrast, thanks to its lightweight, low-profile mesh configuration, OVERNET adds minimal weight and does not generate significant loads on the existing structure. This is a key consideration in existing buildings, where residual load-bearing capacity must be carefully assessed.

Integration with other safety systems

As a permanent collective safety measure installed above the walking surface, OVERNET can be integrated with lifeline systems, anchor points and technical maintenance walkways. The system can also be incorporated into the roof safety plan, in line with the standards set out for fall protection systems in industrial settings.

Natural light, maintenance and compliance with Building Regulations

One aspect often overlooked concerns the impact of permanent coverings on light transmission. A reduction in natural light can affect a building's energy demand and compliance with various local and international Building Regulations. OVERNET keeps the skylight:

• visible;

• accessible for inspection;

• easy to clean;

• replaceable in the future without invasive building works.

The low-profile mesh preserves natural light transmission without converting the skylight into an untested or structurally altered element.

This approach is also consistent with the principle of maintainability highlighted by bodies such as the Rooflight Association, ensuring that skylights remain non-fragile and inspectable while integrating appropriate safety systems to protect those working at height.

OVERNET and PV installations: a winning combination

In a regulatory and technical context where compliance is paramount, the ability to demonstrate certification, system traceability and alignment with industry guidelines becomes a decisive factor in strategic design choices. This is particularly relevant in roof refurbishment projects involving the installation of photovoltaic systems on commercial buildings. The adoption of OVERNET ensures the safe installation of PV panels and, above all, their ongoing maintenance, in full regulatory compliance and with a long-term safety strategy in place.

Consult the OVERNET technical documentation and integrate the system into the roof safety plan from the earliest stages of design.