Chimney Cricket (Saddle)

A cricket, also called a saddle, is a small, peaked sub-roof built on the uphill side of a chimney, skylight or other wide roof penetration. Without one, water running down the slope meets the flat back of the chimney and pools, along with leaves, snow and ice, against the most vulnerable flashing joint. The cricket splits the flow and sends it around both sides.

Code requirement

Under the US International Residential Code, section R903.2.2 (Crickets and Saddles), a cricket or saddle is required on the ridge side of any chimney or penetration more than 30 in (762 mm) wide, measured perpendicular to the slope. It may be covered with sheet metal or with the same material as the roof covering. Unit skylights installed and flashed to the manufacturer's instructions are an exception. Many builders install crickets on narrower chimneys as well.

Construction

A cricket is typically framed from lumber and sheathed with plywood or OSB, forming a small gable whose ridge runs from the back of the chimney up to the main roof. Two short valleys run from the cricket ridge to the upper corners of the chimney. It is then lined with underlayment or self-adhered membrane, flashed into the chimney with counter-flashing, and either covered with metal or roofed over to match the main roof. Code guidance notes that on low slopes the cricket should be steeper than the field so it drains well.

Back gutters (UK)

In UK slating and tiling, the uphill side of a chimney is usually handled with a lead back gutter, a shallow lead tray that carries water to either side, rather than a framed cricket. Very wide chimneys may also get a timber-supported lead saddle.

Other uses

The term cricket is also used for tapered insulation or framing on low-slope roofs that diverts water toward drains and away from curbs, and for the central drainage ridge in some butterfly roofs.