A roof cricket is a small peaked structure built on the uphill side of a chimney or another wide roof penetration. Its job is to divide water and snow so they can move around the obstruction instead of collecting behind it.
For homes in Ithaca, NY, a properly designed cricket can be especially useful because roofs must handle repeated cycles of snow, freezing temperatures, ice, rain, and thawing.
What does a roof cricket look like?
A roof cricket resembles a short, raised ridge that meets the back side of a chimney. It creates two sloped surfaces, allowing water to flow toward each side of the chimney rather than stopping against the masonry.
A cricket is sometimes called a roof saddle. The terms are often used interchangeably, although “cricket” commonly describes a peaked, framed structure that directs water around a chimney or other obstruction.
The cricket is not the chimney cap, flashing, or a decorative roof feature. It is part of the roof’s drainage design.
Why is a cricket needed behind a chimney?
A chimney interrupts the natural slope of a roof. Without a cricket, rainwater and melting snow can collect where the chimney meets the roof. That area depends on flashing to remain watertight, so prolonged moisture exposure can increase the chance of leaks.
A cricket helps by:
- Dividing water around the chimney
- Reducing standing water behind the masonry
- Limiting snow accumulation at the uphill side
- Reducing pressure on chimney flashing
- Helping debris move away from the roof-to-chimney joint
- Lowering the likelihood of repeated moisture entry into the attic
The wider the chimney, the more significant this drainage problem can become. A narrow chimney may shed water without a separate structure, while a broad chimney creates a larger area where water and snow can be trapped.
Do all chimneys require a roof cricket?
No. The need depends on the chimney’s size, location, roof slope, design, and the building code that applies to the project.
Residential code provisions commonly require a cricket or saddle on the ridge side of a chimney or roof penetration that is more than 30 inches wide when measured perpendicular to the roof slope. The exact requirements can vary by code edition and by the type of construction.
A cricket may also be appropriate below that size when the roof has a low slope, the chimney sits in a heavy drainage path, or the local design regularly experiences snow buildup. Conversely, a chimney located close to a roof ridge may not need the same arrangement because water has less area to collect behind it.
The 30-inch measurement is a useful reference, not a substitute for reviewing the complete roof design and applicable code.
How does a roof cricket work in winter?
A cricket does not prevent snow from landing on a roof. Instead, it changes how snow and meltwater interact with the chimney.
Snow can accumulate behind a large chimney because the masonry blocks the normal downhill movement. During a thaw, the lower layers may melt while upper snow remains in place. Water can then move into weak points in the flashing or roofing materials.
A cricket gives that water a sloped path around both sides of the chimney. It can also reduce the size of the snow pocket immediately behind the masonry.
This matters in the local climate, where winter conditions may shift between snowfall, freezing rain, sunshine, and thawing temperatures. Repeated freeze-thaw cycles can enlarge small gaps in flashing and roofing materials over time.
What materials are used to build a cricket?
A cricket may be framed with wood or another approved structural material and covered with a weather-resistant roof material. Its surface generally matches or properly integrates with the surrounding roof covering.
The most important component is often the flashing system. A cricket should be integrated with:
- Step flashing along the sides of the chimney
- Counterflashing set into or secured to the chimney
- Base flashing at the lower transition
- Valley or diverter flashing along the cricket’s drainage paths
- Underlayment beneath the surrounding roofing materials
A cricket covered with shingles but poorly flashed can still leak. Water-shedding parts must overlap in the correct direction, and the chimney-side joints must accommodate movement between masonry and roofing materials.
Can a roof cricket be added to an existing roof?
In many cases, yes, but adding one is more involved than attaching a small piece of metal behind a chimney. The surrounding roofing materials generally need to be removed, the cricket needs proper structural support, and the new flashing must connect with the existing roof system.
The work may be more complicated when:
- The chimney is made of older masonry
- The roof has several layers of roofing material
- The roof deck has moisture damage
- The chimney is close to the ridge
- The roof has a very low slope
- Snow guards, solar equipment, or other features affect drainage
- The roof framing does not provide a suitable support point
If an existing roof is being replaced, that is often the practical time to evaluate whether the chimney design needs a cricket. A roof replacement exposes the deck and flashing areas, making it easier to correct drainage problems before new roofing is installed.
What are common signs of a cricket or chimney drainage problem?
A leak behind a chimney may not appear directly below the chimney. Water can travel along roof sheathing, rafters, insulation, or ceiling materials before becoming visible.
Possible warning signs include:
- Brown or yellow ceiling stains near the chimney
- Damp insulation in the attic
- Soft or deteriorated roof decking
- Rusted fasteners or metal near the chimney
- Peeling paint around an upper-floor ceiling
- Damp masonry or mortar on the uphill side
- Water appearing during snowmelt rather than ordinary rain
- Repeated repairs to the same flashing area
A leak that appears only during thawing weather can point toward snow accumulation or drainage problems, although other causes are possible.
Is a cricket the same as flashing?
No. A cricket is a raised roof structure, while flashing is the material used to direct water away from joints and changes in plane.
The two work together. The cricket creates the slope and drainage path. Flashing seals and guides water around the chimney where different materials meet.
A chimney can have flashing without a cricket, but flashing alone may be asked to manage too much water and snow when the chimney is wide or poorly positioned. A cricket without correctly installed flashing also cannot provide reliable protection.
Do skylights and other roof penetrations need crickets?
Sometimes. Wide skylights, large vents, rooftop equipment, and other penetrations can interfere with drainage in the same way a chimney does.
Building code provisions may require a cricket or saddle for roof penetrations wider than a specified dimension. Some manufactured skylights have approved flashing systems that do not require a separate cricket, provided they are installed according to the applicable instructions.
The key question is whether the obstruction creates an uphill area where water, ice, or snow can collect. Roof geometry matters as much as the object itself.
What should homeowners look for during a roof inspection?
A useful inspection should examine the entire drainage assembly, not just the visible metal. Important questions include:
- Is the chimney wide enough to require a cricket under the applicable code?
- Does the cricket have a continuous slope on both sides?
- Is the flashing integrated with the roofing underlayment?
- Are there open seams, lifted materials, or rusted metal?
- Is the masonry cracked or allowing water behind the counterflashing?
- Is the roof deck dry and structurally sound?
- Are leaves or other debris collecting behind the chimney?
Roof areas near chimneys can be difficult and hazardous to access, especially when wet, icy, or snow-covered. A qualified inspection is warranted when leakage, structural damage, or unsafe access is involved.
A roof cricket is a small feature, but it addresses a large weakness in roof drainage: the point where a broad obstruction interrupts the natural flow of water and snow. Proper sizing, slope, flashing, and integration with the roof covering determine whether it performs as intended.
