Why might preserving an existing building often be more beneficial than demolishing it to build new structures, despite the initial appearance of reducing usable space?

Preserving a building keeps its original materials and energy that were already used to make it, so you avoid the waste of tearing it down and building new parts. Reusing the structure saves the energy that would normally go into making new bricks, steel, and concrete, which is a big part of the building’s carbon footprint. Even if the old building looks smaller, you can often add floors or open spaces inside it to get more usable room, and the old walls and foundations still hold the place, saving the effort of creating new foundations. For example, a century‑old factory can be turned into loft apartments with a new roof, using its sturdy walls and windows, while the new construction would need to pour fresh concrete and steel, burning more energy. Thus, keeping the building reduces waste, saves energy, and often gives you a unique, functional space.