Glass
Flat glass for building: float, heat-strengthened, toughened and chemically strengthened soda-lime glass.
Flat glass (soda-lime silicate)
One base glass, four treatments. Physical values are the same for all; the surface prestress from heat or ion exchange raises the characteristic bending strength from 45 MPa to 70, 120 or 150 MPa.
| Grade | Standard | Characteristic bending strength | Modulus of elasticity | Evidence |
|---|---|---|---|---|
| Float glass (annealed) Ordinary annealed soda-lime float glass: fg,k 45 MPa, E 70 GPa, 2 500 kg/m³. |  EN 572-1/-2 | 45 MPa4 | 70 000 MPa2 |
|
| Heat-strengthened glass Float glass with moderate surface prestress: fb,k 70 MPa; breaks into large pieces that stay in the frame. | EN 1863-1 | 70 MPa3 | 70 000 MPa2 |
|
| Thermally toughened glass Fully tempered safety glass: fb,k 120 MPa; breaks into small blunt fragments. | EN 12150-1 | 120 MPa3 | 70 000 MPa2 |
|
| Thermally toughened glass, enamelled Toughened glass with fired enamel (ceramic frit) on the surface: fb,k 75 MPa on the enamelled face. | EN 12150-1 | 75 MPa1 | 70 000 MPa2 |
|
| Chemically strengthened glass Ion-exchange strengthened glass: fb,k 150 MPa; thin compressive layer, breaks like float glass. | EN 12337-1 | 150 MPa1 | 70 000 MPa2 |
|
Planned groups
- Laminated glass (EN 14449) and interlayers: PVB, acoustic PVB, ionoplast (shear coupling ω)
- Heat-soaked toughened glass (EN 14179), patterned glass, borosilicate (EN 1748-1)
- US: ASTM C1036 flat glass, C1048 heat-strengthened and fully tempered