Can you walk on roof tiles?

Marley does not recommend foot traffic directly on the roof tiles or covering. Cracks or micro-cracks can occur on the roof covering if roofs are trafficked without appropriate access equipment. British Standard BS 8000: Part 6: 1990 'Workmanship on building sites' states that any roof or vertical work in slating or tiling should be 'treated as fragile'. The standard recommends that an adequate number of crawling boards and ladders should be used when accessing completed areas of roof, using packing between boards and tiles to avoid damage.