Before embarking on an ultra-modern steel carport building project, it is important to consider whether this type of project is appropriate or would even be allowed by the neighborhood in which it would be build. Such a structure next to a historic home would not be the best choice, since steel has an unmistakably modern characteristic, and any historic society or zoning board might oppose the project.
The Modernists such as those of the Bauhaus movement and others did work in steel, but they also combined it with other materials. In order to achieve a modern aesthetic, a homeowner might consider combining steel beams with wood panels of high gloss and subtle grain textures. Many Internet outlets offer kits and design ideas to help create the desired effect. Material suppliers of wood and metal may also have suggestions for melding these two mediums.
Steel is a formable material. It will rust, which is in and of itself a modern design element. A carport can utilize steel beams as support members or a steel lattice or armature. Homeowners need to decide if they want a more industrial look -- in which case exposed steel I-beams would be more appropriate -- or a softer, more sculptural look, which would involve finding a steel fabricator to create the more delicate steel lattice.