Valley detailing on torch-down roofing is crucial because valleys are natural channels where water flows most heavily, meaning they require careful installation to prevent leaks. There are three common valley types: woven, closed-cut, and open metal. In woven valleys, strips of torch-down membrane from both roof planes are interlaced to create a continuous, watertight surface. Closed-cut valleys involve one roof plane terminating just short of the valley center, with the other membrane covering the gap, sealed tightly at the edge. Open metal valleys use metal flashing to channel water, with the torch-down membrane carefully trimmed to meet the metal edges. These designs address water flow differently but all rely on proper sealing and correct layering. Over time, valleys may show signs of wear such as blistering, splitting, or peeling, which can be gently checked from the roof surface. It’s wise to use binoculars or a sturdy ladder to examine seams and look for visible cracks or debris buildup that might trap water.
For a safe DIY inspection, ensure your ladder is stable and avoid walking directly on torch-down roofing to prevent damage. Look carefully for any gaps in seams or signs of water pooling, which can indicate poor installation or wear. If you notice frequent puddling, exposed flashing edges, or any bubbling beneath the surface, it’s time to call a roofer with experience in torch-down systems. When you engage a contractor to repair or install valley detailing, ask first how they plan to handle the water channels and what membrane adhesion techniques they will use. Also, inquire about warranty coverage related to valley work, since improper detailing can quickly void material guarantees. Clear communication about these concerns ensures your investment stays protected and your roof performs well for years to come.