But the difference between classical and contemporary architecture is that few of the traditional building and ornamentation methods are still being used, since modern architecture has integrated modern technology by embracing new methods of building, new materials, and an accent on functionality rather than embellishment. For example, one common feature in contemporary architecture is the mixture of stone, wood, and brick wall materials on the same surface.
Nowadays architectural soundness has acquired a new meaning, with the advent of sustainable designing. A dwelling sheathed in solar panels has a very different aesthetic than the usual suburban house. Multi-unit housing which eliminates the thermal bridges created by extensive glazing and concrete decks do not share the aesthetic of glass paneled high rise towers. Passive solar designs often borrow elements from local architectural styles to address local climactic conditions.
The prevailing trends in what is considered architecturally beautiful are slowly changing as more sustainable buildings are erected. The use of local building materials to reduce transportation costs and providing a greater degree of opacity to enhance energy conservation in cladding materials, are some of the criteria of design which are changing the appearance of buildings.
Aesthetics is in the eye of the beholder, and it depends upon the prevailing tastes of the time. A building's functionality, or fitness, is a matter of how well it accommodates the purposes for which it was built. Its structural integrity means soundness - will the building last over time? Historically speaking aesthetics has usually trumped fitness as the overriding factor in architectural design. Classical architecture was preoccupied with articulating features on walls and facades. Modern architecture is equally concerned with aesthetic formalities, such as form following function.