A roofer is a professional who specializes in roof construction. Roofers monitor the entire process of roofing in residential as well as commercial construction. They analyze the construction plans and make sure that the roofing is done in strict accordance with the design. Roofers also determine the materials, substrates and supportive accessories to be used for roof installations. Even the specifications of the beams, trusses and rafters upon which roofs are installed are decided by roofers. Not only do they work on new installations, roofers also work on renovations and roof repair projects. As expected from the job title, roofers ususally need to climb onto rooftops to work. A roofer should therefore not be afraid of heights and should have good balance, as well as reasonable carpentry skills.
Machining is the process of creating or changing parts that are made primarily of metal, and less frequently, of plastic or wood. It may be accomplished by cutting, grinding, drilling, lathing, polishing and other technological processes that are performed to remove excess metal and shape the part. Machinists are individuals who use machinery tools to fabricate parts according to the parameters specified in blueprints, also known as technical drawings. They generally work with materials such as steel, brass, aluminium, copper and sometimes glass, plastic or wood. Machinists have to be proficient in using various machinery equipment because the making of a part frequently requires more than one technological process and tool. Most machinery tools are electrically powered equipment, but several hand tools may also be used occasionally. Machinists are essential workers in industries or fields where replacement parts are frequently needed, especially in emergency situations when the operation of equipment depends on the availability of a specific part.
Structural iron and steel workers install iron or steel beams, girders, and columns to form buildings, bridges, and other structures. They are often referred to as ironworkers. They perform physically demanding and dangerous work.