Perforated Metal Facade Screens and Solar Shading

What it is

Sheet metal — usually aluminium, sometimes stainless or weathering steel — punched with a repeating pattern of holes and formed into panels or cassettes, hung in front of glazing or a solid wall.

It does three jobs at once: shading, screening and appearance.

Specification at a glance

What the screen achieves

Solar shading without blocking the view. Because the screen sits in front of the glass with a gap, it intercepts direct sun before it reaches the glazing, while occupants still see out through the perforations.

Glare control on east and west elevations where low sun defeats overhangs.

Privacy at close-facing elevations, working in one direction because of the brightness difference between inside and outside.

Plant and car park screening, concealing equipment while allowing the ventilation those spaces need.

Where projects go wrong

• Open area chosen visually, not against sun path and daylight needs.
• Wind load assumed negligible because the panel is perforated.
• No unperforated margin, so the panel has no stiffness at its edges and distorts at the fixings.
• Panels rotated on site where the perforation pattern or image has a defined orientation.
• Cleaning and maintenance access not considered. A screen in front of glass makes the glass much harder to clean, and that has to be planned.

Standards referenced

Aluminium sheet under IS 737. Shading and SHGC provisions under ECBC 2017. Wind loading on cladding and screens under IS 875 (Part 3).