Open Valley

Definition: An open valley is a type of roof valley construction where the intersecting roof planes are left exposed, with a visible metal flashing running down the center of the valley. The metal flashing, typically made from materials like aluminum, galvanized steel, or copper, serves to channel water away from the roof and into the gutters, preventing water infiltration at the junction of the two roof slopes.

Open Valley Characteristics:

• Visible Metal Flashing: In an exposed valley, the metal flashing is fully visible, as the shingles or roofing material on either side are cut back from the centerline of the valley, leaving the flashing exposed. This contrasts with a closed valley, where the roofing material covers the valley flashing.
• Water Management: The primary function of an visible valley is to effectively manage water flow from the roof. The exposed metal flashing ensures that water from the intersecting roof planes is channeled efficiently down the valley and into the gutters, reducing the risk of water buildup or leaks.

Applications:

• Steep-Slope Roofs: Open valleys are commonly used in steep-slope roofs, where the slope helps to accelerate water flow, reducing the risk of water accumulation.
• Areas with Heavy Rain or Snow: In regions with significant rainfall or snowfall, these roofing components are preferred for their superior water management capabilities. The exposed metal flashing is less likely to trap snow or ice, reducing the risk of ice dams.
• High-End Roofing Materials: Open valleys are often used with high-end roofing materials like slate, tile, or wood shakes, where the durability and appearance of the metal flashing complement the premium roofing material.