A walk-on rooflight must be structurally designed for its actual location and use. Glass thickness cannot be selected from panel size alone: uniform load, concentrated load, support, edge cover, deflection, post-breakage behaviour and slip resistance all matter.
Residential and public use differ
A private residential terrace does not necessarily have the same loading or crowd conditions as a public, commercial or assembly space. The structural engineer must establish the applicable design actions.
An indicative residential brief may reference a 1.5kN/m² imposed load and a 2.0kN concentrated load, but these figures are not a universal specification.
The build-up is project-specific
Walk-on glazing usually uses multiple structural plies with a suitable structural interlayer. Overhead Glazing specifies SGP interlayers for structural and walk-on glass as company policy.
The frame, bearing width, support stiffness, drainage and anti-slip treatment must be developed alongside the glass calculation.
Project checklist
Never stand on a rooflight unless it has been specifically designed, identified and installed for pedestrian loading.
Bespoke rooflight specification, project coordination and installation across London and the UK.