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Module 9 sur 10 270m 13 exam Qs

Railings, Doors, Showers & Specialty Applications

Glass railings, floors, all-glass doors, shower enclosures, point-supported glazing, spider fittings, acoustic glass, and STC ratings.

  • Describe point-supported glazing systems and spider fitting types
  • Explain acoustic glass construction and STC ratings
  • Identify glass railing and guard requirements per building code
  • Describe all-glass door and shower enclosure requirements
  • State the glass type requirements for railings, guards, and floors

Leçon 1

Point-Supported Glazing & Spider Fittings

Point-Supported Systems

Point-supported glazing (also called structural glass facades) uses individual bolted connections through the glass instead of continuous frames. The glass is supported at discrete points by spider fittings that transfer wind and dead loads to the supporting structure.

Tempered
Required Glass Type for Bolt Holes
Spider Fitting
Multi-Arm Connection Hardware
Countersunk
Bolt Head Type for Flush Exterior

Spider Fittings

Spider fittings are stainless steel connection hardware that holds multiple glass panels at their corners. Types include:

  • 2-arm spider - connects two glass panels
  • 3-arm spider - connects three panels at a corner
  • 4-arm spider - connects four panels at an intersection
  • Each arm has a routable bolt that allows rotation to accommodate glass movement
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Drilled Holes Require Tempered Glass

All holes in point-supported glass must be drilled before tempering. The glass must be tempered or heat-strengthened because the bolt holes create stress concentrations. Annealed glass cannot be used for point-supported applications.

Key Takeaway

Point-supported glazing uses spider fittings at discrete bolt points instead of continuous frames. Glass must be tempered with holes drilled before heat treatment. Spider fittings allow rotation to accommodate glass movement and thermal expansion.