Glass calculator questions
Short answers about the ASTM E1300, AS 1288:2021 and EN 16612:2019 calculators on GlassLoad.com.
About GlassLoad.com
Which standards does GlassLoad.com cover?
Four: ASTM E1300, AS 1288:2021, EN 16612:2019 and IS 16231:2019. Each check is done to one standard, which you choose before the check. GlassLoad.com never mixes or compares standards in one report. GlassLoad.com is an independent tool and is not affiliated with ASTM, Standards Australia or CEN.
Does GlassLoad.com work out the wind or snow load for my building?
No. You enter the load from your project. ASTM E1300 takes one design load. AS 1288 takes the ultimate pressure Pu and the serviceability pressure Ps. EN 16612 takes characteristic wind, snow and self weight loads. GlassLoad.com compares them with the glass.
Does it work in US and SI units?
ASTM E1300 checks work in inches and psf, or millimeters and kPa, and show results in both. AS 1288, EN 16612 and IS 16231 checks use SI units only: millimeters, kPa and, for EN 16612 and IS 16231, N/mm².
Is there a calculation report?
Yes. Each check can be downloaded as a PDF that lists the inputs, the intermediate values, the warnings and the result. The AS 1288, EN 16612 and IS 16231 reports are on A4 paper. Results are to be verified by a qualified professional.
How do I get AS 1288, EN 16612 or IS 16231 on my account?
Choose the standard on the sign up form. A free account allows 100 checks a day until subscription is available, for the one standard you chose, with all its editions. In the Standard list, the other standards show a lock. To change, open your Account page and request a switch. You are warned first, and the switch applies 24 hours later. You can cancel before then. Visitors who are not signed in can run ASTM E1300 or IS 16231 checks, counted in the same ten trial checks; laminated and insulating glass need a free account.
Can I see worked examples before I sign up?
Yes. The Examples page lists worked examples for ASTM E1300, AS 1288:2021 and EN 16612:2019. They are open to everyone, signed in or not, and each one can be printed as a PDF.
ASTM E1300
What does the ASTM E1300 calculator check?
It checks the load resistance of a rectangular lite of glass against the design load and reports the approximate deflection. It covers monolithic glass, laminated glass of two plies and double or triple insulating glass. Monolithic glass can be simply supported on four sides, on three sides with one free edge, on two opposite sides, or on one edge as a cantilever. You can also enter a glass angle for sloped glass.
Which editions of E1300 does it cover?
E1300 09a, E1300 12a, E1300 16 and E1300 24. You pick the edition, and the thicknesses offered, the scope limit and the deflection appendix follow that edition.
What is the non factored load (NFL) of glass?
The NFL is the load a lite of annealed glass can carry for a short duration load, for the given size and thickness. It is what the E1300 charts print. GlassLoad.com calculates it for you, so you do not read a chart.
How is the load resistance of glass found?
Load resistance is the NFL multiplied by the glass type factor for the glass type and load duration. The check passes when the design load is at most the load resistance.
What are the glass type factors?
For a single lite and a short duration load: annealed glass 1.0, heat strengthened glass 2.0, fully tempered glass 4.0. For a long duration load: 0.43, 1.3 and 3.0.
How accurate is the glass deflection calculator?
The deflection is approximate. It comes from the E1300 appendix equation, a curve fit to test data, and can differ from the true value by about 10 percent. Where deflection governs, verify it by an independent method.
Can it find the minimum glass thickness?
Yes. The minimum thickness finder checks every thickness offered by the edition for your size, glass type, load duration and design load, and marks the thinnest one that passes. It needs a free account.
What is not covered yet by the E1300 calculator?
Laminated glass of more than two plies, non rectangular shapes, glass guards and balustrades, point supported glass and thermal stress.
AS 1288:2021
What does the AS 1288 calculator check?
It checks one rectangular pane against the wind pressures you enter, with the simplified method of Section 4 of AS 1288:2021. Strength compares your span B with the allowable span. Deflection compares the span over thickness with the Figure 4.35 value on the span over 60 basis. Deflection has its own verdict and does not change the strength result.
Which glass and supports does the AS 1288 calculator cover?
Annealed, heat strengthened and toughened glass in the thicknesses of Table 4.1. The glass can be monolithic, laminated of two equal sheets with a PVB interlayer, or insulating in a double or triple unit. Supports are four edges, two opposite edges, or three edges, which is checked as two edges spanning the free edge.
Which loads do I enter for AS 1288?
The ultimate pressure Pu and the serviceability pressure Ps in kPa, already combined to AS/NZS 1170. The simplified method covers pressures up to 10.0 kPa. GlassLoad.com does not work out the wind pressure.
Which edition of AS 1288 is used, and what is not covered?
AS 1288:2021 only. It is the one edition offered, so there is no edition to pick. Not covered: human impact, balustrades and barriers, fins, point fixings, sloped glazing, AS 1288:2006, and laminated glass with unequal sheets or an interlayer other than PVB.
Can the AS 1288 calculator find the glass thickness?
Yes. The minimum thickness finder gives the thinnest thickness of Table 4.1 that passes both strength and deflection.
EN 16612:2019
What does the EN 16612 calculator check?
It checks the strength and deflection of one rectangular pane under the loads you enter, to EN 16612:2019, which is published in the UK as BS EN 16612. Strength compares the maximum stress with the design strength of the glass. Deflection compares w with the span over 65 or 50 mm, whichever is less. You can change the deflection limit.
Which glass and supports does the EN 16612 calculator cover?
Annealed float, toughened and heat strengthened glass, as produced or sandblasted. The glass can be monolithic, laminated of two plies (Annex D) or a double insulating unit (Annex C). Supports are four, three, two or one edge. EN 16612 gives coefficients for four edges only, so the other supports use beam theory or the GlassLoad.com plate analysis, and the report says so.
Which loads do I enter for EN 16612?
Characteristic wind, snow and self weight of sloped glass, in kPa, each with its duration. GlassLoad.com applies the partial factors and the combination factors, checks every combination and shows the factors in the report. You can change the EN 1990 combination factors. GlassLoad.com does not work out wind or snow loads.
Which edition of EN 16612 is used, and what is not covered?
EN 16612:2019 only, with the recommended values of the standard and no national annex. Not covered: cavity temperature from sunlight, triple insulating units, edge seal forces, point fixings, fins and non rectangular glass. There is no minimum thickness finder for EN 16612. Use Check a thickness and try other thicknesses.