Architecture Puzzler #69

Cristo has wrapped it with 1.1 million square feet (102,000 square meters) of canvas and Foster & Partners have renovated and restored it. Which building do we refer to?

This material's proponents claim that it is harder than walnut and more stable than oak. Technically a grass, the product has come into use as a substitute for tongue-and-groove hardwood flooring. What material am I referring to?