Chimney Flashings Flashcards
What are the five types of chimney flashings?
1.Step flashing
2.Counter-flashing
3.Apron flashing
4.Cricket flashing
5.Backer flashing
Where is step flashing installed, and how is it designed?
Step flashing is installed where the roof intersects a vertical sidewall, with individual pieces of metal stepping up with each shingle course.
What is the purpose of counter-flashing?
Counter-flashing protects the top edges of other flashings to prevent water intrusion.
Where is apron flashing typically installed?
Apron flashing is used where a roof intersects a headwall, such as the downslope side of a dormer or a chimney.
What is the function of cricket flashing?
Cricket flashing diverts water around chimneys or roof penetrations. It is recommended for chimneys wider than 24–30 inches.
When is backer flashing used?
Backer flashing is installed on the upslope backside of narrow chimneys (less than 24 inches) that do not require a cricket.
What is a common defect associated with missing counter-flashing?
Missing counter-flashing exposes the top edge of step flashing to water penetration, often sealed temporarily with non-standard sealant.
How should counter-flashing be installed on masonry chimneys for best practice?
The top edge of counter-flashing should be inserted at least 1 inch into the masonry joint or a groove cut in the masonry.
What is a defect if a chimney wider than 24 inches lacks cricket flashing?
Without cricket flashing, water is not diverted properly, even if backer flashing is installed, making it a defect.
What does sealed valleys on a cricket indicate, and why is this poor practice?
Sealed valleys with roofing sealant indicate water intrusion problems. Sealant is not a permanent solution and is considered poor practice.
According to standard chimney installation requirements, a typical chimney must be at least ____ feet high.
A) 4
B) 3
C) 2
B) 3
Explanation: Chimneys must be at least 3 feet high from the roof penetration point and extend 2 feet higher than any structure within 10 feet to ensure proper draft and fire safety.
When a chimney is located within 10 feet of a roof ridge, how much higher must it extend above the ridge?
A) 2 feet
B) 10 feet
C) 3 feet
A) 2 feet
Explanation: The “3-2-10 Rule” states that chimneys must be at least 3 feet above the highest roof penetration and extend 2 feet higher than any structure within 10 feet to ensure proper airflow and prevent downdrafts.
The term used to describe the chipping or breaking off of masonry or mortar on a chimney is:
A) Pointing
B) Efflorescence
C) Spalling
C) Spalling
Explanation: Spalling is the process where masonry deteriorates due to moisture intrusion and freeze-thaw cycles, causing bricks or mortar to flake or break apart.
The process of repairing missing or deteriorated mortar joints between bricks is called:
A) Re-pointing
B) Grouting
C) Mudding
A) Re-pointing
Explanation: Re-pointing involves removing damaged mortar and replacing it with fresh mortar to maintain the structural integrity of masonry.
What is the primary difference between a chimney cap and a rain cap?
A) A chimney cap protects the structure, while a rain cap protects the inside of the flue.
B) A rain cap protects the structure, while a chimney cap protects the inside of the flue.
A) A chimney cap protects the structure, while a rain cap protects the inside of the flue.
Explanation: A chimney cap helps prevent animals, debris, and sparks from exiting, while a rain cap primarily prevents water intrusion into the flue.
T/F: All chimneys are required to have a spark arrestor fitted.
A) True
B) False
B) False
Explanation: While spark arrestors are highly recommended for fire safety, they are not required on all chimneys, particularly in areas with low fire risk. However, they are mandated in some jurisdictions, especially where wildfires are a concern.
What is the required clearance between a manufactured chimney and combustible materials?
A) 2 inches
B) 6 inches
C) 3 inches
A) 2 inches
Explanation: Manufactured chimneys must have at least 2 inches of clearance from combustible materials to reduce fire risk, as per standard safety codes.
Most manufactured chimneys come equipped with which of the following?
A) Damper extension
B) Rodent screen
C) Rain cap
C) Rain cap
Explanation: Rain caps are standard on most manufactured chimneys to prevent water from entering the flue and causing internal damage.
The connection between a manufactured chimney flue and the roof is called a:
A) Boot
B) Bucket
C) Thimble
C) Thimble
Explanation: A thimble is the approved connection that allows a manufactured chimney to pass through a combustible wall or roof safely.
T/F: Manufactured chimney systems are not required to maintain the same separation from adjoining structures as traditional chimneys.
A) True
B) False
B) False
Explanation: Manufactured chimney systems must adhere to the same clearance and separation requirements as traditional chimneys to prevent fire hazards and ensure proper ventilation.
