Why DGU Load Sharing Matters
In a DGU, the cavity links the panes through pressure change. Under wind pressure or suction, part of the action may be carried by the directly loaded pane and part may be transferred to the opposite pane depending on pane stiffness and cavity behavior.
Outer Pane and Inner Pane Results
A useful DGU review should identify which pane is being checked and show pane-level stress and deflection output. The governing pane may change between pressure, suction, ULS stress, and SLS deflection cases.
Effect of Laminated Panes
If one pane is laminated and the other pane is monolithic, their stiffness can be very different. VitraLab accounts for the selected build-up so the DGU load sharing is reviewed with the relevant pane stiffness rather than treating both panes as identical.
Wind Pressure and Wind Suction
Positive and negative wind actions can produce different pane effects. The outer pane and inner pane should both be reviewed because suction, pressure, and transferred cavity effects can govern different checks.
What Is Not Published
The public guide explains the load-sharing concept for transparency, but it does not publish the full internal implementation, coefficients, or calculation tables. The result remains a calculation aid that must be checked against project requirements.
Engineering Review
For DGU glass, review pane dimensions, cavity thickness, outer pane build-up, inner pane build-up, support condition, wind actions, ULS stress, SLS deflection, and output warnings before making project decisions.
Frequently Asked Questions
Does a DGU put all wind load on the outer pane?
Not necessarily. DGU behavior depends on pane stiffness and cavity interaction, so both panes should be reviewed.
Can the inner pane govern a DGU check?
Yes. Depending on stiffness, build-up, pressure or suction direction, and limit state, either the outer pane or inner pane may govern.
Does laminated glass affect DGU load sharing?
Yes. A laminated pane may have different effective stiffness from a monolithic pane, which can affect load sharing and pane-level results.
Should DGU stress and deflection be checked separately?
Yes. ULS stress and SLS deflection are separate checks, and the governing pane or action can differ between them.