What is the header for in carpentry?

Answer 1

Headers are the reinforced crosspieces above doorways and windows in residential or commercial buildings.

The reason for the reinforced crosspieces above doorways and windows, is to support the weight of the trusses that land every two feet on a load bearing wall. In the South West there are a lot to tile roofs which are heavy, so supporting all this weight above a 12' wide/3 panel door for example, is very important. The wider the opening is, the taller the header needs to be.

**More correctly, a header is a framing member that spans studs, joists or trusses so as to share a load with parallel members. An example would be a header that terminates a series of joists to permit an opening in the floor area for stairs. This is known as a joist header. Thus the opening does not have to be for a door or window. In doors and windows, it is more accurately referred to as a lintel, although many will call a door/window crossmember a "header" and use "lintel" as the steel angle that does the same job in a brick wall. Also, the pieces are not usually reinforced themselves, but are assembled in a way that the built-up member can handle a load factor dictated by building code. Height of the members is certainly a factor as mentioned above, but if wood is used, species is also a factor. If the opening span requires more strength than wood or wood laminations can provide, the material would have to be something else, such as steel, and would not commonly be referred to as a header in that case.