What is the minimum width for valley lining when using metal for open roof valleys?

The minimum width for valley lining in open roof valleys when using metal is specified as 24 inches. This requirement is important for several reasons related to both function and durability of roofing systems.

A wider valley lining provides adequate coverage and protection against water infiltration, ensuring that any water flowing down the roof has enough surface area to properly divert into the gutter system. This is especially critical in areas where roof slopes meet, as these zones can be prone to water accumulation and concentrated runoff, increasing the potential for leaks and water damage.

In addition to waterproofing, a minimum width of 24 inches helps to support the structural integrity of the roofing system and the valley itself. With enough metal lining, there is a reduced risk of wear and tear or damage caused by thermal expansion, debris accumulation, or physical stress from weather events.

By adhering to this minimum width requirement, builders help ensure the longevity and effectiveness of open roof valleys, which is crucial for maintaining the overall health of the building’s roof structure.