Abstract: A point fixing apparatus is described. The point fixing apparatus is suitable for mounting an insulated glass unit (IGU) to a support structure, the IGU having first and second panes of glass spaced apart from one another, the point fixing apparatus including: a spacer apparatus for spacing the first and second panes from one another; a first clamping block configured for clamping the first glass pane against the spacer apparatus; a second clamping block configured for clamping the second glass pane against the spacer apparatus; and one or more stop devices configured to inhibit overtightening of the clamping blocks against the panes and spacer apparatus, the one or more stop devices disposed between the clamping blocks when assembled.