One important part of sustainable design is thinking through a product's entire life cycle. What happens when a product comes to the end of its life? An interesting take on this is the Jesus College Cambridge. In the 1980s one of the building's large oak beams was rotting. The team tasked with replacing the beam pulled out the college's 300 year old building records for reference. They were impressed to discover that the building's original architects had anticipated this eventuality and planted a suitable oak tree on the college campus to replace the beam.