• 6 MB per 25 cm x 5 cm volume
• 20 volumes per shelf
• 8 shelves per bookcase
• 160 volumes or 960 MB per bookcase

According to en:WP:Size of Wikipedia, the compressed size of all articles is 22.14 GB without media. That means there should be 22.14/0.006 (approximately 3690) volumes, or 23.1 bookcases.

Bookcases are drawn in groups of five to facilitate counting. Some trivial details:

• Bookcases are 2.5 metres (8 ft 2 in) high and 1.05 metres (3 ft 5 in) wide
• Each volume is drawn to be precisely 25 centimetres (9.8 in) high and 5 centimetres (2.0 in) thick
  • Assuming the front and rear covers are each 2.5 millimetres (0.098 in) thick, disregarding any title/cover pages, that means each page is 0.11 millimetres (0.0043 in) thick