Technical Booklet V Glazing·Page 13·2.6
Small panes dimensions and area limits
Small panes must have a width not exceeding 250 mm and an area not exceeding 0.5 m². These dimensions are measured between glazing beads or similar fixings.
A small pane may be an isolated pane or one of a number of panes contained within glazing bars (see Diagram 2.2), traditional leaded lights or copper-lights and should have –
(a) a width of not more than 250 mm; and
(b) an area of not more than 0.5 m²,
each measured between glazing beads or similar fixings.
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