Tower Bridge, London: laminated glass floors on walkways more than 40 m up.

Reference project — not a Eurowindow project. This article summarises public information from the sources listed at the end, with our own commentary. Images belong to their owners and are embedded directly from Pinterest with a link back to the source.

The project at a glance

• Name: Tower Bridge, London, UK
• The bridge: Opened 30 June 1894; 940 ft (290 m) long; pedestrian walkways 143 ft (44 m) above the river at high tide (per Wikipedia)
• Glass floors: Installed 2014; West Walkway floor opened to the public on 1 November, East Walkway floor unveiled 1 December; each took six weeks with 20 workers (per Tower Bridge website)
• Floor size: Each floor 11.5 m long, 1.8 m wide, six panels; each panel about 530 kg (per Tower Bridge website)
• Build-up: Tower Bridge website: five layers, 70 mm thick in total; Britglass (2015): seven layers, 80 mm, plus a sacrificial top layer — the two sources differ, depending on source
• Sacrificial layer: The top layer is replaced regularly, about every 18 months; dark spots give grip (per Tower Bridge website)
• Glazing contractor: Glassolutions designed and manufactured the glass under a £250,000 contract (per Britglass)

What stands out in the glass floors

According to the Tower Bridge website, each glass floor is 11.5 m long and 1.8 m wide, made of six panels weighing around 530 kg each, installed in 2014 on the West and East walkways. The top layer is a “sacrificial layer”, replaced about every 18 months so visitors keep a clear view; dark spots on the surface provide grip.

Sources differ on the build-up: the Tower Bridge site says five layers, 70 mm in total, while a 2015 Britglass item says seven layers, 80 mm, plus a sacrificial layer. The height above the river is also given as 42 m or 43.5 m. We quote both so readers can compare.

Note: this is a reference project, not a Eurowindow project.

Our take

From glass floors on a historic London bridge, three lessons for structural glass and glass balustrades:

1. Structural glass should include a replaceable sacrificial layer. The outer layer takes the scratches while inner layers carry the load. See Eurowindow glass balustrades.
2. Load and safety must be verified against standards. Safety and load requirements apply to any walkable or guarding glass.
3. Laminated glass is not the same as single-layer toughened glass. If the outer ply breaks, the remaining plies still carry people.

If you are weighing options for a high-rise project, send your brief to the Eurowindow technical team to discuss specifics.

Sources

• Tower Bridge – Glass Floors — Glass Floors page
• Wikipedia — Tower Bridge
• Britglass — Glass walkways for Tower Bridge
• Pinterest — pin: Condé Nast Traveler – pin reference

This article is for reference only and does not imply Eurowindow took part in this project. If you own an image or content and would like it changed or removed, please contact sonhn@eurowindow.biz; we will act immediately.