We defined a 'properly designed' cricket valley as having a slope of 1/8 inch per foot, plus or minus 10 percent. To demonstrate the relationship between existing slope and distance between drainage points, we have run calculations to determine cricket valley slope based on existing underlying slope, distance between drainage points, and cricket width. If the drainage points rest in the middle of the roof, as seen in Photo 1, a cricket is built on both sides of the low point on the existing slope, creating a diamond-shaped pattern. If the drainage points are next to a wall, the configuration shown would be used. The anatomy of a cricket is shown in Figure 1. But many contractors - and some design professionals - do not understand the mechanics of proper cricket design.Ĭrickets can be constructed of wood, concrete, lightweight concrete or gypsum, but the most commonly used material is tapered polyisocyanurate (ISO) insulation panels. Properly designed, they virtually eliminate ponding (see Photo 1). Crickets, also known as saddles, are structures built between roof drainage points to move water laterally across the roof, diverting it to the drainage points.

Roof cricket