A door header are a structural beam that is installed above a door opening. A door header is used to distribute the weight that is present above the opening. The beams will carry the weight that is place above the doorway from the structure above the doorway, and it will transfer that weight to the studs that is located on each side of the doorway.
If there is no door header installed above a doorway, then the framing above that doorway will not have support for the weight of the structure above that doorway, and it may sag over time. Because a door header is used to support the weight above a doorway, the size of the door header must be determined based off the weight that it must support and the width of the opening. In buildings with load-bearing walls, the door header must be able to support a significant amount of weight from the structure above the doorway.
How to Choose the Right Door Header
Therefore, the door header in a load-bearing wall will have to be deeper than a door header installed in a non-load-bearing wall. The wider the opening in the doorway, the more deeper the header will need to be in order to support the structure above the doorway. In order to easily determine the size of the door header necessary for a specific doorway opening, many people will use a chart that illustrates the relationship between the width of the doorway opening and the depth of the door header necessary to support the structure above that doorway.
The type of wall in which the doorway is installed will also impact the size of the door header that must be installed in that opening. For interior walls that are not meant to be load-bearing walls, the door header will be much smaller. For instance, two 2-by-4 or 2-by-6 boards may be used for the header for such doors.
These measurement are sufficient for non-load-bearing doors since there is no structural weight that must be placed onto the header. Additionally, using such small door headers allow for other structural components, such as electrical wire or plumbing pipes, to pass through the wall to the other side. For exterior walls or for door openings that are particualaraly wide, much larger door headers will be required.
This is due to the fact that the exterior walls of a building will be supporting more weight than interior walls. For instance, a 36 inch exterior door may require a doubled 2-by-10 header, whereas a wider patio door may require a doubled 2-by-12 header or laminated veneer lumber beams. The wider the opening, the more an opening such as a patio door will require a door header that can span that opening.
Beyond considering the type of wall in which the doorway will be installed and the size of the doorway opening, other factor will also impact the size of the door header that will be used for that doorway. The rough opening for the doorway will impact the size of the header. The rough opening is the space that will be created within the walls for the doorway.
The rough opening must be larger than the actual size of the doorway. To create the rough opening, you must add two inches to the width of the doorway opening and two inches to the height of the doorway. The extra space in the rough opening will allow for small shims to be inserted into the rough opening to ensure that the door close evenly and correctly.
If the rough opening is not created to these specifications, the doorway may be difficult to install or may not open and close as it is suppose to. Some specific types of doors will require specialized door headers to be installed above those doors. For instance, garage doors are very wide and often require an engineered beam or a beam create by a structural engineer.
Additionally, French doors are very heavy due to the amount of glass that is included in those doors. As a result, the door header that is used for French doors will need to be constructed in such a way that it can support that weight of the door without shifting over time. For openings in walls that are wider than standard doors or door headers, laminated veneer lumber (LVL) may be required.
LVL is constructed as multiple thin layer of wood glued together. This type of door header is more stronger than standard door headers made from sawn lumber. The size of the door header for a doorway must be chosen correctly.
If the size of the door header is too large for the doorway, then the door header will be much more expensive than necessary and will take up more space within the wall than is necessary. If the size of the door header is too small for the doorway, the door header may sag over time, which may lead to the drywall cracking or the doors becomes stuck in their door frames. In either case, the individual must measure the width of the doorway opening and the load that the doorway will have to bear.
Based upon these measurements and the weight of the load that the doorway will have to bear, the individual can purchase a door header that is of an appropriate size.
