In the United States, modern house construction techniques include light-frame construction (in areas with access to supplies of wood) and adobe or sometimes rammed-earth construction (in arid regions with scarce wood-resources). Some areas use brick almost exclusively, and quarried stone has long provided foundations and walls. To some extent, aluminum and steel have displaced some traditional building materials. Increasingly popular alternative construction materials include insulating concrete forms (foam forms filled with concrete), structural insulated panels (foam panels faced with oriented strand board or fiber cement), light-gauge steel, and steel framing. More generally, people often build houses out of the nearest available material, and often tradition or culture govern construction-materials, so whole towns, areas, counties or even states/countries may be built out of one main type of material. For example, a large portion of American houses use wood, while most British and many European houses use stone, brick, or mud.