Terminology of Roof Safety Mesh for Roofing Construction

In order to better understand roof safety mesh, the definitions about safety mesh below apply.

Fastener

A ring fastener (or 'hog ring') used for joining side laps of roof safety mesh.

Fixing

Connections between the roof safety mesh and the roof member.

Joints

Connections between rolls or sections of roof safety mesh.

Lapping

Where the sides of roof safety mesh are overlayed to prevent a gap forming between the two.

Longitudinal wires

Wires of roof safety mesh that span between purlins and are welded to transverse wires; also known as line wires.

Mesh sag

A measurement of downward deflection of roof safety mesh between two roof members.

Purlin

Beam, parallel to the eaves, that is supported by rafters and gives support to roof cladding.

Roof member

A supporting member to which the roof safety mesh is attached, and which has the structural capacity to ensure the performance requirements. Typically purlins or rafters, but may include bridge bars or other members.

Roof safety mesh

Steel wire mesh, comprising longitudinal and transverse wires, fixed to an appropriate roof member to prevent persons from falling during installation of roofing materials and support insulation materials. Roof safety mesh is intended to control the risk of fall hazards over the entire roof area, including penetrations, both during construction and after the building enters service.

Staples

Component used for fixing the ends of longitudinal wires to appropriate timber roof members.

Transverse wires

Wires of roof safety mesh that are parallel to the purlins and are welded to the longitudinal wires; also known as cross-wires.

Ultraviolet (UV) protection

The stabilization process applied to materials susceptible to deterioration from UV radiation.