The worst-case scenario is a structural failure of a section of your house.
What Is a Window Header?
A header is a beam that horizontally spans an opening, such as a doorway.
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For example, a window header spans the top of a window opening.
The header is the structural elementmuch like a bridgethat allows the space below to be open, not closed.
Another way to understand a window header is to consider what’s being replaced.
The Spruce / Michela Buttignol
There would ordinarily be an exterior wall of wood-frame construction in that space.
Studs spaced every 16 or 24 inches would form a robust wall system with vertical forces.
The window header allows you to remove some studs while maintaining the wall’s strength.
Common Window Header Sizes
Window headers are usually made of two dimensional sawn lumber pieces placed side-by-side.
Most wall systems use two-by-fours, which are 3 1/2 inches wide.
Thicker beams can achieve greater strength for beams.
But this is impossible in walls since the walls always have to maintain that 3-1/2-inch depth.
So, the solution is to go up: to use wider pieces of lumber that extend vertically higher.
Contact a structural engineer, licensed contractor, or architect.
Wider buildings decrease the span length of window headers.
Heavy snow or other factors can also change window header sizes.
That’s why it’s important to tailor all the buildings to local codes.
Some do-it-yourselfers and builders overbuild the window header out of caution.
Overbuilding will increase the cost just slightly.
Yet, as window widths increase, four jack studs (and two king studs) may be required.
Laminated veneer lumber uses thin veneer layers to create larger beams.
The layers are glued together in the factory and held under high pressure until bonded.
The strength and stiffness of LVL exceed those of normal sawn dimensional lumber.
LVL’s value is evident in its wide spans, such as garage door headers orFrench doors.
