Prel-Point glass consists of a monolithic glass panel or a sealed unit made of laminated, tempered or heat-strengthened glass. The perimeter of the glass is grinded or polished. These glass panels make it possible to create interior or exterior mullionsless glazing applications. Holes drilled into the glass serve to fasten the glass panels to the back-up structure with anchoring systems using bolts, screw fittings and spiders. The back-up structure itself can be made of glass, metal rods or cable netting. Glass facades assembled using these systems are striking in appearance: from the outside, the glass panels seem to be held in place simply by a few metal caps! 

• Three kinds of glass are available :

Prel-Point trempered : monolithic tempered or heat-strengthened glass in thicknesses of 3/8" (10 mm), 1/2" (12 mm), 5/8" (15 mm) or 3/4" (19 mm). 

Prel-Point laminated : laminated tempered or heat-strengthened glass usually made up of an exterior lite 3/8" (10 mm) or 1/2" (12 mm) thick and an interior light a minimum of 1/4" (6 mm) thick.

Prel-Point insulating : sealed unit usually made up of an exterior lite 3/8" (10 mm) or 1/2" (12 mm) thick, a 1/2" (12.7 mm) airspace and an interior light a minimum of 1/4" (6 mm) thick. The lites must be tempered or heat-strengthened. 

• Prel-Point tempered or laminated panels can be flat or bent. For more information, go to: Prel-Form - laminated bent glass and Prel-Form - tempered bent glass. 
• Prel-Point panels can be made of ultra-clear low iron glass. Neutral in color, this glass is more transparent than standard clear glass. 
• Prel-Point panels can be made of different types of decorative glass, such as ceramic frit coated or laminated glass made with decorative film, etc. For more information, go to: Prel-Coat - ceramic frit coated glass, Prel-Design - silkscreened glass and Prel-Lam - laminated glass. 
• Prel-Point insulating glass can also be made of solar control glass. For more information, go to: Thermalite - sealed units. 
• To conserve the integrity and durability of insulating glass, the holes drilled through the Prel-Point insulating panels are hermetically sealed using specially designed gaskets and assembled with highly-resistant sealants. 
• To limit the risk of spontaneous breakage in tempered glass, it is recommended that Prel-Point glass panels undergo heat-soaked testing. For more information, go to: Prel-Gard HST - heat-soaked test. 
• The structural performance and aesthetic appearance of all-glass curtain walls depends primarily on the type of glass used and the quality of its fabrication. Prel-Point spider glass by Prelco is produced under our ISO 9001:2000 certified quality management system, ensuring constant and rigorous product quality.

Notes:
The glass panels used in mullionless glass facades are subjected to permanent loads, additional wind load and wind pressure and suction. These loads put a heavy strain on the holes drilled in the glass panels. Structural design calculations by qualified engineers are essential with this kind of glass facades.

Technical data - Prel-Point tempered glass

• Exterior curtain walls: entryways, atriums, hotels, shopping malls, office buildings, sports stadiums
• Interior glass cladding: balconies, elevators, decorative glass elements, shop windows 
• Glass roofs: canopies, covered outdoor walkways, sloped glazing

Prel-Point tempered glass complies with the following norms: ASTM C 1036, ASTM C 1048, ANSI Z97.1, CPSC 16 CFR-1201 and CAN/CGSB 12.1.

Prel-Point laminated glass complies with the following norms: ASTM C1172, CPSC 16 CFR 1201 class 1 and 2, UL 972, UL 952 and CAN2 12.1 class 1 and 2. 

Prel-Point insulating glass complies with the following norms: CAN/CGSB 12.8, ASTM E 773 and ASTM E 774. 
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