Control risks from roof work

Roof work is the single largest cause of fatal falls from height in the construction industry. Falls from roofs account for approximately a quarter of all deaths from falls at work. These incidents affect not only large construction sites but also small maintenance and repair jobs where workers may be on a roof for only a short time.

As an employer, principal contractor, or building owner commissioning roof work, you have a legal duty to ensure the work is planned, supervised, and carried out safely. The Work at Height Regulations 2005 apply to all roof work without exception, regardless of the roof height, duration of work, or type of building.

Planning roof work

Every roof work task requires planning before anyone goes onto the roof. The level of planning should be proportionate to the risk, but even apparently simple jobs such as clearing gutters or replacing a tile need a brief assessment. The key questions are:

• Can the work be done without going onto the roof? (Telescopic tools, drones for inspection, ground-level gutter vacuums)
• If someone must go on the roof, what are the specific hazards? (Edges, fragile materials, pitch, weather, proximity to power lines)
• What equipment and precautions will prevent a fall?
• Who will supervise the work?
• What is the rescue plan if someone falls or is injured?

For construction projects that fall under the Construction (Design and Management) Regulations 2015 (CDM 2015), the principal designer must consider roof work safety during the design stage, and the principal contractor must plan and manage it on site.

Edge protection

Edge protection is the primary means of preventing falls from roofs. It is a form of collective protection, meaning it protects everyone in the area without relying on individual behaviour or equipment.

Flat roofs:

• Guardrails at least 950mm high along all open edges
• Toe boards at least 150mm high to prevent materials rolling off
• Intermediate rail or other infill to prevent people falling between the top rail and toe board
• Edge protection must be strong enough to withstand a person falling against it

Pitched roofs:

• Edge protection at the eaves to prevent falls from the roof edge
• On roofs pitched above 30 degrees, use roof ladders or crawling boards to distribute weight and provide secure footing
• Consider scaffold platforms at eaves level to provide both a working platform and edge protection
• On very steep pitches, additional measures such as safety nets or harnesses may be needed alongside edge protection

Fragile surfaces

Fragile roofing materials are responsible for a disproportionate number of roof work deaths. Workers fall through materials that look solid but cannot support their weight. You must assume a roof surface is fragile unless you have clear evidence otherwise.

Identifying fragile materials:

• Fibre cement sheets -- commonly found on industrial and agricultural buildings. They become more fragile with age and weathering
• Rooflights -- plastic or glass rooflights may not be visible under dirt, moss, or paint. They are almost always fragile
• Liner panels -- the inner skin of built-up cladding systems. They will not support a person's weight
• Corroded metal sheets -- metal roofing that has corroded may not support weight even if it appears intact
• Wood wool slabs -- used as permanent formwork in older buildings. Often fragile

Precautions for fragile surfaces:

• Warning signs at all access points stating "Fragile roof -- use crawling boards"
• Platforms, walkways, or crawling boards that span the fragile material
• Safety nets positioned as close as practicable beneath the fragile surface
• Never walk directly on fragile materials under any circumstances
• Protect adjacent areas where someone could fall through a fragile surface if they strayed from the safe route

Safety nets and fall arrest

Where edge protection alone is not sufficient, additional measures are needed:

Safety nets:

• Position as close as practicable beneath the work area -- keep the fall distance into the net as short as possible, typically no more than 2 metres below the working level
• Must be rigged by competent net riggers (typically holding a FASET certificate)
• Inspect before first use and at regular intervals
• Ensure there is sufficient clearance beneath the net for the deflection when arresting a fall

Personal fall arrest systems:

• Use only where collective protection (edge protection, nets) is not reasonably practicable
• Comprises a full body harness, lanyard, energy absorber, and a secure anchor point
• Anchor points must be capable of withstanding the forces generated by an arrested fall (typically rated to at least 12kN per person)
• Ensure the total fall distance (including lanyard length, energy absorber deployment, and harness stretch) does not allow the worker to hit the ground or a lower level
• A rescue plan must be in place before using fall arrest -- suspension in a harness can cause suspension trauma, which can develop within minutes - prompt rescue is essential

How to manage roof work safely

Particular risks on short-duration jobs

Many fatal roof falls happen during short jobs -- replacing a few tiles, clearing a gutter, or inspecting a leak. The temptation to skip precautions because the job will "only take a few minutes" is a major contributor to deaths. The law does not provide an exemption for short-duration work. If someone could fall and be injured, the full requirements of the Work at Height Regulations apply regardless of how long the task takes.

For short jobs, consider:

• Tower scaffolds or podium steps for gutter and eaves work
• MEWPs (cherry pickers) for inspection or access to specific areas
• Temporary edge protection systems designed for quick installation

What happens next

Roof work safety should form part of your wider work at height management system. For the overarching legal requirements, see Comply with work at height regulations. If your site uses scaffolding, see Ensure scaffolding safety on your site. For MEWP use as an alternative to roof access, see Use MEWPs (cherry pickers and scissor lifts) safely.