Whenever a large building project is designed, there are thousands of details to be considered. Each phase of construction must be outlined before decisions about materials are made. Materials used in the project will be affected by the desired look of the project once finished. Glass, steel and concrete are materials that produce a unique look when used. They also have different durability factors. Each one may have a specific place within the building construction, but this must be weighed against the need for structural strength. Building designers are well aware of these factors and their importance. They often factor in the materials necessary as part of the look of the finished design.