Heat Treated Glass


Related Resources

Temperfect Specification

 


JEB Temperfect™
Heat-Treated Glass

JE Berkowitz has three state-of-the-art horizontal tempering ovens that produce the highest quality of heat strengthened and fully tempered glass. Heat-Treated glass is:

  • Governed by ASTM C1048-04, ASTM C1279-06 and ASTM C1651-08

  • Individually tested by SGCC

  • Not warranted against breakage, mechanical or thermal

  • Intended Uses - specify safety glazing and/or increased strength for mechanical, thermal or deflection purposes

Quality Specification
  • Rollwave distortion for 1/4" thick glass can be targeted and verified not to exceed .003" peak to valley.

  • Bow and Warp for 1/4" glass can be targeted not to exceed 1/32" per lineal foot.

  1. Directional Heat Treating is recommended and should be parallel to the width dimension. (maximum 84”)

  2. Optics – Peak to Valley Roller Mark DistortionHeat-treated glass, assembled into either IG units or laminated glass, or both, and installed in a sloped or vertical application, may exhibit increases levels of distortion. This is INHERENT in the HT process, with other factors, including temperature, atmosphere, barometric changes and the glazing systems impact on the glass surface.

    1. No ASTM standard currently exists for tolerances, but an ASTM methodology for measurement, in-plant on monolithic heat treated glass, using either an approved flat bottom or 3-point gauge exists.

    2. Industry guideline for ¼” heat-treated glass suggest a tolerance of not to exceed .006” peak to valley, excluding the lead and trail edges (10”) with an allowable .010”. JEBs internal target is to maintain a limit of .003 peak to valley, excluding the lead and trail edges (10”) with an allowable .008”.

  3. Heat-treated glass, assembled into either IG units or laminated glass, or both, and installed in a sloped or vertical application, may exhibit increases levels of distortion. This is INHERENT in the HT process, with other factors, including temperature, atmosphere, barometric changes and the glazing systems impact on the glass surface.

  4. JEB recommends the use of full size mockups for visual and approval purposes.

HS Applications
  • Windows

  • Insulating Glass Units (IGUs)

  • Laminated Glass

Heat-Strengthened Glass (HS)

Heat-Strengthened Glass is flat glass that has been heat-treated to have a surface compression between 3,500 and 7,500 psi (24 to 52 MPa) resulting in a surface compression approximately twice of annealed glass and meets the requirements of ASTM C 1048, kind HS. It is intended for general glazing, where additional strength is desired to withstand wind load and thermal stress. Heat Strengthened glass is NOT a safety glazing material.

FT Applications
  • Storefronts

  • Point Supported Glass Wall Systems

  • Windows

  • Insulating Glass Units (IGUs)

  • All Glass Doors

  • Entrances

  • Railings

  • Commercial Shower Doors

 

Fully Tempered Glass (FT)

Fully Tempered Glass is flat glass that has been heat-treated to have a minimum surface compression of 10,000 psi (69MPa) resulting in resistance to impact of approximately four times that of annealed glass.  Fully tempered glass will meet the requirements of ANSI Z97.1 and CPSC 16 CFR 1201 and is considered a safety glazing material.

 
Tempering Capacity

Fully Tempered Glass

Minimum Tempering Size

4 1/2" x 16"

Maximum Tempering Size

96" x 180"

 
Recommended Maximum Sizing

Fully Tempered Glass

(Based on glass thickness) 

1/8" Clear

40" x 76"

3/16" Clear

80" x 130"

1/4" Clear & Tint

96" x 180"

3/8" Clear & Tint

96" x 180"

1/2" Clear & Tint   

96" x 180"

3/4" Clear

80" x 160"

1/8" Low E

34" X 76"

3/16" Low E

48" X 96"

1/4" Low E

84" x 142"


(*Consult JEB for applicable maximum glass sizes)