CSCS Roof Cladding key terms

A written document describing how a specific work task will be carried out safely, including the sequence of steps, the hazards involved and the control measures to be applied.

A careful examination of what in a work activity could cause harm to people, so that you can judge whether enough precautions have been taken or more should be done.

The order of preference for managing risk: eliminate the hazard, reduce it, control it at source, then rely on personal protective equipment as a last resort.

Clothing or equipment worn or held by a worker to protect against one or more risks to health and safety, such as a helmet, gloves, safety footwear or eye protection.

Equipment worn over the nose and mouth, or a powered hood, that filters or supplies air to protect the wearer from breathing in dust, fibres or fumes.

Equipment, such as a harness connected to a lanyard and anchor, that stops a person who falls from height and limits the distance and force of the fall.

Equipment that prevents a person from reaching a position where a fall could occur, for example a harness and short lanyard that keeps the worker away from an unprotected edge.

Work carried out in any place where, if no precautions were taken, a person could fall a distance liable to cause personal injury, including work on a roof or near an edge.

A physical barrier such as guardrails or a scaffold edge system placed around the perimeter of a roof to stop people or materials falling off the edge.

A roof covering or structure that will not safely support the weight of a person and could give way underfoot, such as many rooflights, asbestos cement sheets or corroded metal sheets.

A ladder with hooks or a ridge hook that is designed to rest on a roof surface and spread the load, giving a secure footing for access to the roof slope.

A formal written authorisation that allows a specified high-risk task to proceed under stated conditions for a limited time, and that records who is responsible for the area.

The process of disconnecting and locking off an energy source, such as electricity or gas, so that equipment cannot be started or become live while work is being carried out.

A procedure in which a switch or valve is physically locked in the safe position and the key held by the person working, preventing accidental re-energising.

A group of naturally occurring fibrous minerals once widely used in building materials, which can cause serious lung disease if fibres are breathed in during cutting, drilling or removal.

Any material, chemical or biological agent that can harm health if inhaled, swallowed or brought into contact with the skin or eyes, including solvents, dusts and adhesives.

An assessment of the risks from substances hazardous to health used or produced at work, and of the controls needed, required under the Control of Substances Hazardous to Health Regulations.

The transporting or supporting of a load by hand or bodily force, including lifting, lowering, pushing, pulling and carrying, which must be assessed to avoid injury.

A short, informal briefing given to a work team on site about a particular safety topic, task or change, used to reinforce safe working arrangements.

An unplanned incident that did not cause injury or damage but had the potential to do so, and which should be reported so that lessons can be learned.

A report made to the enforcing authority under the Reporting of Injuries, Diseases and Dangerous Occurrences Regulations when a specified serious incident, injury or dangerous occurrence happens at work.

The on-site record in which all accidents and injuries, however minor, are entered so that there is a written history available for investigation and legal purposes.

A document supplied with a hazardous product that sets out its hazards, safe handling and storage requirements, first-aid measures and emergency procedures.

The outer weatherproof layer fixed over a roof structure, made from sheets or panels of metal, fibre cement, plastic or similar material, which sheds water and protects the building below.

A horizontal structural member that runs across the roof slope and supports the roof covering or cladding sheets, transferring their load to the rafters or frame.

A small horizontal timber or metal member fixed over rafters or a substrate to carry and support tiles, slates or cladding panels at the correct spacing.

A sloping structural member that forms the roof slope and carries the roof loads down to the wall plate or ridge, often supporting battens or purlins.

The highest line or apex of a pitched roof where two opposing slopes meet, usually finished with a ridge capping or ridge sheet to make it weathertight.

The lower edge of a roof slope that overhangs the wall, where the cladding or covering terminates and where rainwater is collected or discharged.

A vertical board or trim fixed along the eaves that closes the gap between the roof edge and the wall and often carries the gutter.

A strip of metal or other material formed and fixed to make a watertight joint where the roof covering meets a wall, chimney, valley or other upstand.

The overlap between the long edges of adjacent cladding sheets or panels, which seals the joint and prevents water being driven through by wind or running sideways.

The overlap between the ends of two cladding sheets laid one above the other down the slope, sized so that water runs over the joint without leaking.

The angle of a roof slope measured from the horizontal, which determines the type of covering suitable and how quickly rainwater will run off.

The screws, bolts, clips or nails used to secure cladding sheets, flashings and trims to the structure, chosen for the material and exposure conditions.

The expansion and contraction of cladding sheets as temperature changes, which must be allowed for in fixing and joint design to avoid buckling or pulling fixings.

Water that forms when moist air cools and reaches its dew point on a cold surface, often on the underside of roof cladding, and which can cause damp and corrosion.

A membrane placed on the warm side of the roof insulation to limit the passage of moisture-laden air into the roof construction and reduce the risk of condensation.

The provision of air movement into and out of a roof space or construction, which removes moisture and helps prevent condensation and timber decay.