When header spans exceed 4 feet, what must be done to the header and trimmer?

When header spans exceed 4 feet, doubling the header is essential for ensuring the structural integrity and support of the wall above. This requirement is rooted in the need to adequately distribute load and prevent sagging or failure of the framing system. Doubling the header increases its load-bearing capacity by providing additional material, which enhances stability and distributes weight more effectively across the trimmers.

In residential construction, proper framing practices are critical for durability and safety. Headers play a significant role in transferring loads from above, such as walls or roofs, to the support structure below. When the span exceeds a certain limit, like 4 feet, it indicates an increased potential for deflection and stress that may compromise the structural system. By doubling the header, builders ensure compliance with code requirements and provide a stronger framework that meets safety standards.

While reinforcement, replacement, or shortening could address some concerns, they do not provide the same level of assurance that doubling the header does in maintaining structural integrity for spans over 4 feet.