Technical Booklet D Structure·Page 84·4C.41
Size and location of major openings
Buildings or annexes may have one or two major openings in only one wall, each not exceeding 2.1 m in height, with combined width not exceeding 5 m.
One or two major openings not more than 2.1 m in height are permitted in one wall of the building or annex only. The width of a single opening or the combined width of two openings should not exceed 5 m.
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