Expo roof, Hannover, Germany, completed 2000, designed by Herzog + Partner, featuring laminated veneer lumber (LVL), glulam triangular braces and solid silver fir uprights. Each of the ten 'umbrellas' covers an area of 1,600 m2 (40 by 40 m) and stands around 26 m high. The wooden elements are fixed together with steel brackets and castings. A waterproof membrane, suspended 50 mm above the roof, protects the wood from being permanently damp.