Technical Booklet V Glazing·Page 13·2.6
Small panes annealed glass thickness
Annealed glass in small panes must be at least 6 mm thick, except in traditional leaded or copper-lights where 4 mm glass is acceptable.
Small panes of annealed glass should be not less than 6 mm in thickness, except in traditional leaded or copper-lights in which 4 mm glass is acceptable.
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