ASTM E1300 09a glass load calculator
This ASTM E1300 09a calculator checks glass load resistance, deflection and glass thickness. E1300 09a is the 2009 edition of ASTM E1300, the standard practice for determining the load resistance of glass in buildings. It was approved in June 2009. GlassLoad.com can run a check to this edition for one rectangular lite of monolithic glass with four sided, three sided, two sided or one sided support, or of laminated glass of two plies with four sided or three sided support. GlassLoad.com is not affiliated with ASTM.
What GlassLoad.com checks under E1300 09a
- Thicknesses offered: 2.5, 3, 4, 5, 6, 8, 10, 12, 16, 19 and 22 mm. The calculation uses the minimum thickness of each designation from Table 4, unless you enter a thickness override. This edition has no 2.0 mm and no 25 mm designation.
- Scope load limit: 210 psf, wind, snow and self weight combined. A design load above it is still checked, with a warning that it is outside the scope of the edition.
- Glass types and durations: annealed, heat strengthened and fully tempered glass, for a short duration load (3 seconds) or a long duration load (30 days).
- Deflection: the approximate center of glass deflection, read from the E1300 deflection chart of the nominal thickness, or from the equation in Appendix X2 where the chart gives no value. The report names Appendix X2 for this edition. Appendix X1 of E1300 09a is a different method, a nondimensional chart.
- Probability of breakage: Appendix X3 gives an approximate method for annealed glass under a 60 second load. For annealed glass GlassLoad.com shows a value from the glass failure model written in Annex A2 of E1300 24 instead, and the report says so in a warning.
What differs from the other editions
- The scope limit is 210 psf. The charts of this edition stop at the 210 psf contour. E1300 12a, 16 and 24 go to 315 psf.
- Deflection rules: E1300 12a, 16 and 24 state three rules in clause X1.1.1, which are rounding to the nearest millimeter, a caution below one third of the load resistance and an aspect ratio capped at 5. E1300 09a does not state them, so a check to E1300 09a does not apply them: no rounding, no cap at aspect ratio 5, and above the range of Appendix X2 another method gives the result.
- Probability of breakage: 09a has the optional Appendix X3 and describes the probability in lites per 1000. E1300 16 and E1300 24 have a full model in Annex A2 and E1300 12a has no procedure.
- Insulating and laminated glass: some tables and the laminate thickness designation rule differ in 09a. GlassLoad.com applies the 09a designation rule to laminated glass and reads the laminated glass charts that 09a prints; insulating glass is not covered yet.
For monolithic glass on four sides, the printed non factored load charts of the editions agree closely. GlassLoad.com therefore uses the same load calculation for all of them, and the edition changes the thicknesses, the scope limit, the appendix names and the warning wording.
Run a check with E1300 09a
Open the calculator and pick E1300 09a as the edition. See also the guides, how the calculation works, the questions and answers and the guide on glass deflection. The other edition pages are E1300 24, E1300 16 and E1300 12a. Results are to be verified by a qualified professional.
Worked examples
These are the worked examples printed in E1300 09a that GlassLoad.com can run. GlassLoad.com computed each one from the printed inputs. Every example has its own page with all the steps. All worked examples
- Example 1, A2.1: Non factored load of a 47.24 by 59.06 in, 1/4 in annealed plate
- Example 2, A2.2: Non factored load of a 50 by 60 in, 1/4 in annealed plate
- Example 3, A2.3: Double glazed unit, 1/4 in tempered over 5/16 in laminated
- Example 4, A2.4: Center of glass deflection, 37.99 by 75.98 in, 1/4 in
- Example 5, A2.5: Center of glass deflection, 60 by 180 in, 3/8 in
- Example 6, A2.6: Triple glazed unit, 1/8, 3/32 and 1/8 in annealed lites
- Example 9, X2.2.1: Deflection with a measured thickness, converted from SI
- Example 10, X2.2.7: Deflection with a measured thickness, inch pound units
Not available in GlassLoad.com
- Examples 7 and 8, X1.5: The deflection chart method of Appendix X1 with a chart reading. The same cases are run as Examples 9 and 10 with the polynomial. Not available in GlassLoad.com.
- Examples 11 and 12, X3.3: Probability of breakage for a 60 second load by the Appendix X3 procedure. GlassLoad.com does not run it. Not available in GlassLoad.com.
- Example 13, X11.7: Appendix X9 effective thickness of a laminated beam, a laminated cantilever with a line load. Not available in GlassLoad.com.
GlassLoad.com is an independent tool and is not affiliated with ASTM.