How it works

A cricket is framed from dimensional lumber sheathed in plywood, then covered in step flashing, counterflashing, and the roof’s primary covering material. Its peak runs from the upslope chimney face to the roof ridge, splitting incoming water into two streams that flow around the chimney corners. The geometry mimics a small gable, and on wider chimneys it can be substantial enough to walk on.

Without a cricket, leaves and debris accumulate against the chimney’s upslope face during fall and spring, holding moisture against the brick and flashing. Over time this saturates mortar joints, rusts step flashing nails, and produces interior ceiling stains around the chimney chase. Sweeps inspect cricket condition during CSIA Level 1 visits because flashing failures often coincide with chimney moisture damage downstream.

DFW context

DFW’s mature tree canopy in neighborhoods such as Lakewood, University Park, and Colleyville drops oak and pecan debris that collects on roofs through fall. A cricket keeps that debris moving past the chimney instead of trapping it against the brick. The June 2025 hail event also damaged thousands of crickets across North Texas, and replacements should use 26-gauge or heavier galvanized steel to handle the next storm cycle.

Related terms

• [Saddle](/glossary/saddle/)
• [Step flashing](/glossary/step-flashing/)
• [Counterflashing](/glossary/counterflashing/)
• [Spalling](/glossary/spalling/)

Sources

• IRC 2021, Section R1003.20
• NFPA 211 (2024), Section 10.4.4
• CSIA Reference Manual