The article talks about making old buildings more energy efficient by adding a new roof on top of the existing one. The researchers created a unique design with solar panels, a special membrane, and insulation to save energy and produce electricity. They used computer simulations to show that this new roof idea can lower energy use and make the building better at handling heat from outside. The main aim was to develop a smart roof idea to transform an old building into a waterproof and energy-generating place.