King-Size Sheets. TallWall lets you sheathe today’s taller walls without creating horizontal seams. The extra-long OSB panels come in 9- and 10-foot lengths. When installed vertically, says the maker, the product reduces air infiltration by up to 60 percent and makes the wall assembly much stronger, especially if it overlaps joist areas. A 10-foot panel costs about $13.50. Norbord, 416/365-0705, tallwallosb.com.