A roof cricket is a raised, wedge-shaped structure installed behind a chimney or another wide roof penetration. Its purpose is to divide flowing water and direct it around the obstruction instead of allowing water, snow, and debris to collect against it.
For homes in Ithaca, NY, roof crickets can be especially useful because roofs must manage a combination of rain, freeze-thaw cycles, ice, and seasonal snow. A cricket is not decorative. It is part of the roof’s drainage and flashing system.
What does a roof cricket look like?
A cricket resembles a small peaked roof built into the main roof. It is usually located on the uphill, or ridge-facing, side of a chimney. The high point of the cricket sits near the centerline behind the chimney, while its sloping sides guide water toward the left and right.
The structure typically includes:
- A framed or tapered base
- Roof sheathing over the framing
- Underlayment
- Roofing material
- Metal flashing where the cricket meets the chimney and roof
A cricket may be covered with shingles, metal, or another roofing material that matches the surrounding assembly. The most visible part is often the metal cap or flashing at the chimney intersection.
Why is a cricket necessary?
Without a cricket, a chimney acts like a dam on a sloped roof. Water running down the roof reaches the uphill side of the chimney and has to change direction around both sides. That can create concentrated runoff and a vulnerable area where water may linger.
A properly designed cricket helps by:
- Splitting water before it reaches the chimney
- Reducing standing water at the uphill chimney wall
- Directing snow and meltwater away from the chimney base
- Limiting the amount of debris trapped behind the chimney
- Supporting more reliable flashing performance
The cricket does not make the roof waterproof by itself. Its effectiveness depends on the full system, including the roof covering, underlayment, step flashing, counterflashing, and drainage paths.
Is a cricket the same as flashing?
No. A cricket and flashing perform different jobs.
Flashing is made from water-resistant material, usually metal or a purpose-made membrane, and is installed at roof transitions, joints, walls, chimneys, and penetrations. It creates a controlled path for water and keeps water from entering exposed seams.
A cricket is a sloped structural feature. It changes the shape of the roof so water and snow are directed around a wide obstruction. Flashing is then installed over and around the cricket to protect the joints.
A roof can have flashing around a chimney without having a cricket. In that situation, the flashing may still be correctly installed, but the chimney can remain a significant obstruction to drainage.
When is a cricket required?
Under the current model roof provisions adopted in New York’s residential building code, a cricket or saddle is generally required on the ridge side of a chimney or other penetration that is more than 30 inches wide when measured across the roof slope. The exact requirements can depend on the building type, roof design, construction date, and code edition governing the work.
Some smaller chimneys do not require a cricket under that dimensional rule. That does not mean every smaller chimney is free from drainage concerns. A cricket may still be useful when the roof has a low slope, the chimney is unusually tall or wide, the area collects snow, or the existing flashing has a history of leakage.
Skylights and other roof penetrations may follow different requirements, particularly when they are manufactured and installed according to approved instructions.
Why does local weather make crickets useful?
The community experiences weather that repeatedly tests roof details. Rain can be followed by freezing temperatures, causing water in small gaps to expand. Snow can accumulate on the uphill side of a chimney, then melt unevenly during warmer periods.
A cricket helps shed water and reduce the amount of snow pressed against the chimney. It can also reduce the likelihood that leaves, twigs, and roof granules will form a damp pocket behind the obstruction.
This matters on both newer and older homes. Older properties may have additions, intersecting rooflines, masonry chimneys, or past repairs that create complicated drainage patterns. A cricket is particularly valuable when the chimney sits below a roof ridge rather than directly through the ridge.
What problems can occur when a cricket is missing or defective?
A missing cricket does not automatically mean that a roof is leaking. However, the uphill side of a wide chimney is a known area of concern.
Possible problems include:
- Water stains on ceilings or upper-floor walls near the chimney
- Damp insulation or roof sheathing
- Peeling paint or damaged plaster around the chimney
- Rusted or deteriorated flashing
- Moss or algae growth in a persistently wet area
- Ice buildup near the chimney during winter
- Shingles that curl, loosen, or wear faster behind the chimney
- Damp masonry, especially near the chimney’s uphill side
Leaks do not always appear directly beside the chimney. Water can travel along roof sheathing, rafters, insulation, or interior finishes before becoming visible. A ceiling stain may therefore indicate a problem higher on the roof or slightly upslope from the visible damage.
What does a properly built cricket include?
A sound cricket should be integrated with the roof rather than simply fastened over existing shingles. Its shape should provide a clear drainage path on both sides, and the covering should be securely connected to the surrounding roof system.
Important details include:
- Adequate height and width for the chimney and roof slope
- A smooth transition from the roof into the cricket
- Durable flashing at the cricket’s lower edges
- Counterflashing that is properly embedded or secured at the chimney
- No exposed gaps where water can enter
- Compatible materials that will not react with one another
- Adequate support beneath the roof covering
The cricket’s dimensions should be based on the roof slope, the chimney size, expected snow conditions, and the surrounding roof layout. A very small raised strip may not provide meaningful drainage, while an oversized structure can create unnecessary flashing joints.
Can a cricket be added to an existing roof?
In many cases, yes, but adding one is more involved than placing a cover over the existing shingles. The roofing around the chimney usually must be opened so the cricket can be framed, sheathed, integrated with underlayment, and flashed correctly.
The condition of the chimney also matters. Masonry joints, chimney caps, and existing counterflashing may need attention at the same time. If the chimney has shifted, cracked, or absorbed moisture, repairing only the roof surface may not solve the underlying problem.
Because roof work involves fall hazards and chimney work can involve unstable masonry or heat-producing flues, inspection and construction should be handled carefully. Building-code requirements may also apply when a roof or chimney is altered.
How can homeowners recognize a potential cricket issue?
From the ground, look for a chimney that is noticeably wider than nearby roof penetrations and sits below the roof ridge. The uphill area should not appear to hold standing water, heavy debris, or repeated snow buildup.
Inside the home, watch for staining or dampness that appears after rain, snowmelt, or a freeze-thaw period. A recurring stain near a chimney deserves attention even if it dries between storms.
A roof cricket is a small component, but it solves a large drainage problem. By dividing water and snow before they reach a wide chimney, it helps protect the flashing, roof structure, insulation, and interior finishes from repeated moisture exposure.
