Building Materials

The availability of suitable materials fostered the crafts to exploit them and influenced the shapes of buildings. Large areas of the world were once forested and their inhabitants developed carpentry. Although it has become relatively scarce, timber remains an important building material.

Many kinds of stone lend themselves to building. Stone and marble were chosen for important monuments because they are incombustible and can be expected to endure. Stone is also a sculptural material; stone architecture was often integral with stone sculpture. The use of stone has declined, however, because a number of other materials are more amenable to industrial use and assembly.

Some regions lack both timber and stone; their peoples used the earth itself, tamping certain mixtures into walls or forming them into bricks to be dried in the sun. Later they baked these substances in kilns, producing a range of bricks and tiles with greater durability.

Thus early cultures used substances occurring in their environment and invented the tools, skills and technologies to exploit a variety of materials, creating a legacy that continues to inform more industrialized methods.

Building with stones or bricks is called masonry. The elements cohere through gravity or the use of mortar, first composed of lime and sand. The Romans found a natural cement that, combined with inert substances, produced concrete. They usually faced this with materials that would give a better finish. In the early 19th century a truly waterproof cement was developed, the key ingredient of modern concrete.

In the 19th century also, steel suddenly became abundant; rolling mills turned out shapes that could make structural frames stronger than the traditional wooden frames. Moreover, steel rods could be positioned in wet concrete so as to greatly improve the versatility of the material, giving impetus early in the 20th century to new forms facilitated by reinforced concrete construction. The subsequent profusion of aluminum and its anodized coatings provided cladding (surfacing) material that was lightweight and virtually maintenance free. Glass was known in pre-history and is celebrated for its contributions to Gothic architecture. Its quality and availability have been enormously enhanced by industrial processing, which has revolutionized the exploitation of natural light and transparency.