Some 147 ft (45 m) high, the terraces of the Fondation Louis Vuitton are also places of exhibition for large works under the gaze of the Bois de Boulogne and Paris. A special coating covered with Rocheron stones was created to support the weight of the slabs. They have unprecedented dimensions, being 29.5 ft (90 cm) long, 16.4 ft (50 cm) wide, and 0.42 ft to 0.55 ft (13 to 17 cm) thick. The slabs were custom designed and cut directly into the quarry. Window cleaning machines weighing an average of 6.5 tons, it was, therefore, necessary to find a resistant system to equip the terraces.