What thickness is structural glass flooring?

Structural glass floors in domestic settings typically use 3-ply laminated toughened glass totalling approximately 33mm (3 x 10mm with 1.52mm PVB interlayers). Commercial and assembly floors use 4-ply configurations of 50mm+ (4 x 12mm with SGP interlayers). Exact thickness depends on span, load and support conditions.

How much does structural glass cost in the UK?

Structural glass typically costs £600-£1,200/m² supply and install depending on application and specification. Walk-on glass floors cost £800-£1,500/m². Glass beams and fins cost more due to specialist fabrication. SentryGlas Plus (SGP) lamination adds approximately 40% over standard PVB.

What is SentryGlas Plus (SGP)?

SGP is a high-performance interlayer for laminated glass that is approximately 100 times stiffer than standard PVB (polyvinyl butyral). It provides much better post-breakage performance and is specified for structural applications where the glass must maintain integrity after one ply breaks, such as overhead glazing and floors.

Does structural glass need Building Regulations approval?

Yes, structural glass requires full structural calculations by a chartered engineer and Building Regulations approval. Walk-on glass must comply with Part K (protection from falling), Part A (structure) and Part N (glazing safety). A specialist structural glass engineer should design the system.

How heavy is structural glass?

Glass weighs approximately 2.5 kg per m² per mm of thickness. A typical 33mm domestic glass floor panel weighs about 82 kg/m². A 50mm commercial floor panel weighs approximately 125 kg/m². Supporting structure must be designed for this dead load plus the imposed (live) load.

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Structural Glass Calculator

Calculate structural glass thickness, weight and cost for floors, beams, roofs and walls. Guidance on laminated glass specification for UK structural applications.

ApplicationDetermines minimum specification

Glass TypeSGP is strongest but most expensive

Panel Width

Width of each glass panel

Panel Length

Length of each glass panel

Number of Panels

Total panels required

Price per m²

Supply and install cost

How We Calculate This

This calculator estimates the required glass thickness, number of plies, weight and cost for structural glass applications.

The formula

Weight = Panel area × Total thickness × 2.5 kg/m²/mm

Floors: 3-ply (domestic) or 4-ply (commercial) laminated
Beams/fins: typically 3-ply laminated
Roofs/canopies: minimum 2-ply laminated (overhead safety)
SGP interlayer recommended for structural applications

Frequently Asked Questions

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Last updated: March 2026

All calculations are estimates. Verify with your supplier.