Spider Fittings for Glass Facades: Types, Arms and Where to Use Them

Those star-shaped stainless fittings holding large glass facades are spider fittings. They let glass span big openings with almost no visible frame.

How they work

A spider fitting bolts to a structural support (a post, fin or truss) and reaches out with 1 to 4 arms. Each arm connects to a routel — a bolt that passes through a countersunk hole in the toughened glass. Load transfers from glass to structure through these points instead of a frame.

Arm configurations

• 1-arm — edges and perimeters where only one panel corner is supported
• 2-arm — along vertical or horizontal edges between two panels
• 3-arm — junctions of three panels, often at facade edges
• 4-arm — the classic centre fitting where four panel corners meet

Where they are used

• Shopfronts and showroom facades
• Atriums and curtain walls
• Entrance canopies and skylights
• Feature glass walls in hotels and offices

Critical requirements

• Glass must be toughened and pre-drilled/countersunk by the glass processor — never drill on site
• Use SS 316 for external facades; 304 for protected interiors
• Structural design should be checked by an engineer for wind load
• Order fittings and routels together so thread sizes match

Finish

Mirror polish is traditional for facades; satin is increasingly used for a softer look. PVD black is popular in contemporary retail. Compare finishes.

Kiran Steel India stocks spider fittings, routels and patch fittings in 304 and 316.