Roof Flashing Flashcards
What is the importance of roof flashing in a roofing system?
Roof flashing is crucial for preventing leaks. Even if the roof covering is new, improperly installed or poor-condition flashing can lead to leaks.
Where is flashing necessary on a roof?
Flashing is needed at any interface between a roof plane and another component, including:
Other roof planes
Walls
Chimneys
Vents
Skylights
What is counter-flashing?
Counter-flashing is a secondary flashing that overlaps the primary flashing to provide extra protection against water intrusion.
What materials are commonly used for roof flashing?
Galvanized steel
Copper
Aluminum (not recommended for coastal areas)
Lead
Stainless steel
What are the main types of roof flashing?
Edge flashing
Ridge and hip caps
Valley flashing
Roof-wall flashing
Roof-roof flashing
Chimney and vent flashing
Skylight flashing
What is edge flashing (drip edge) and its function?
Edge flashing, also called drip edge flashing, prevents rainwater from wicking into the roof sheathing or decking. It ensures drips fall away from the roof structure.
What does the 2018 IRC Section R905.2.8.5 require for edge flashing?
Edge flashing must:
Be installed at all eaves and rake edges
Extend at least 1/4 inch below roof sheathing
Extend back onto the roof deck at least 2 inches
Be fastened to the roof deck every 12 inches
How should the underlayment and drip edge flashing be installed at the eaves?
The underlayment should overlap or cover the drip edge flashing to protect it.
How should the underlayment and drip edge flashing be installed at the rake edges?
The metal drip edge should overlap or cover the underlayment to prevent wind-driven rain from entering under the underlayment.
What is the purpose of drip edge flashing at the eaves?
At the eaves (gutter location), drip edge flashing protects the roof deck by ensuring rainwater flows away from the roof sheathing. It is covered by the underlayment, often a “peel-and-stick” or “ice and water shield” material.
How is drip edge flashing installed along the rake edge of the roof?
At the rake edge, the metal drip edge flashing is installed on top of the underlayment to prevent wind-driven rain from getting underneath.
Why might it be difficult to see multiple layers of shingles on a roof?
A second drip edge flashing may be installed with a second roof covering, hiding the additional layers of shingles. Inspecting at the eaves is necessary to identify multiple layers.
What are ridge and hip flashings, and what are they made from?
Ridge and hip flashings, often called ridge caps, are made from the same material as the roof covering. Examples:
Asphalt shingles: Cut-down 3-tab shingles or special ridge shingles
Slate tiles: Terra cotta or metal (copper/lead)
Wood shakes/shingles: Special ridge caps, trimmed shingles, or cedar planks
Clay/concrete tiles: Specially manufactured caps, nailed or mortared
What is the correct size of asphalt shingle ridge caps?
Asphalt shingle ridge caps should extend 4 inches down from the roof peak on both sides.
What materials are commonly used for ridge caps on different roof types?
Asphalt shingles: 3-tab shingles or special ridge caps
Slate tiles: Terra cotta, copper, or lead
Clay/concrete tiles: Specially manufactured caps
Metal roofs: Ridge caps matching the roof style
What underlayment is required under ridge caps?
A metal or heavy roofing felt should be installed under the ridge cap, extending below the uppermost course of shingles or shakes.
What issues are common with clay and concrete tile ridge caps?
Clay and concrete tile ridge caps often show:
Damaged tiles
Cracked mortar
What are the three types of ridge caps for wood shake and shingle roofs?
Special ridge caps made by manufacturers (two thick shingles connected).
Ridge caps formed on-site by trimming and side-jointing standard shingles or shakes.
Cedar planks butted together (typically 1x6 timber).
What is unique about ridge caps for asbestos cement roofs?
They use specially molded roof cap tiles that are overlaid to hide nail heads, similar to asphalt tiles.
Edge Flashing (Drip Edge) - Code Requirement
Q: According to the 2018 IRC (R905.2.8.5), why is edge flashing (drip edge) required?
A) To improve roof aesthetics
B) To prevent water from wicking into the roof deck
C) To provide additional insulation
D) To reduce roof weight
B) To prevent water from wicking into the roof deck
Edge Flashing (Drip Edge) - Placement
Q: Where is drip edge flashing installed?
A) Only at the eaves
B) Only at the rake edges
C) At eaves and rake edges
D) Only where shingles overlap
C) At eaves and rake edges
Edge Flashing (Drip Edge) - Dimensions
Q: How far should the drip edge extend below the sheathing and onto the roof deck?
A) ¼ inch below, 2 inches up
B) 1 inch below, 3 inches up
C) ½ inch below, 1 inch up
D) 2 inches below, 4 inches up
A) ¼ inch below, 2 inches up
Underlayment Installation at Eaves
Q: At eaves, how should underlayment be installed with drip edge?
A) Underlayment should be under the drip edge
B) Underlayment should cover the drip edge
C) Underlayment placement doesn’t matter
D) Drip edge should cover the underlayment
B) Underlayment should cover the drip edge
Underlayment Installation at Rake Edges
Q: At rake edges, how should underlayment be installed with drip edge?
A) Underlayment should cover the drip edge
B) Drip edge should cover the underlayment
C) Underlayment should be removed at rake edges
D) There are no specific requirements
B) Drip edge should cover the underlayment
Q: How should ridge and hip flashing materials be selected?
A) They must match the roof material
B) They should be different from the roof for contrast
C) They should always be made of copper
D) They are not necessary
A) They must match the roof material
Asphalt Shingle Ridge Flashing
Q: What is commonly used as ridge flashing for asphalt shingle roofs?
A) Metal caps
B) Cut-down 3-tab shingles or special ridge caps
C) Terra cotta caps
D) Slate ridge caps
B) Cut-down 3-tab shingles or special ridge caps
Architectural Shingles - Ridge Flashing
Q: Why do architectural shingles require specially designed ridge caps?
A) To match the roof color
B) To prevent cracking
C) To improve ventilation
D) To reduce costs
B) To prevent cracking
Slate Roofs - Ridge Flashing
Q: What materials are commonly used for ridge flashing on slate roofs?
A) Aluminum
B) Terra cotta or metal (copper/lead)
C) Plastic caps
D) Asphalt shingles
B) Terra cotta or metal (copper/lead)
Wood Shakes/Shingles - Ridge Flashing
Q: Which of the following is NOT a common ridge cap type for wood shake/shingle roofs?
A) Pre-manufactured ridge caps
B) On-site trimmed and side-jointed shakes
C) 1x6 cedar plank ridge caps
D) Concrete ridge caps
D) Concrete ridge caps
Metal Roofs - Ridge Flashing
Q: What type of ridge system is used for metal tile roofs?
A) No ridge system is required
B) The ridge system mimics the tile design
C) Standard shingle caps are used
D) Mortared ridge caps
B) The ridge system mimics the tile design
Flashing Inspection Focus
Q: What should inspectors look for when inspecting ridge and hip flashing?
A) Missing or improperly installed flashings
B) Excessive caulking
C) Flashing color consistency
D) The length of ridge caps
A) Missing or improperly installed flashings
Common Ridge Cap Defects
Q: Which of the following is NOT a common ridge cap issue?
A) Loose, cracked, or missing caps
B) Mortar damage on tile and slate caps
C) Incorrect underlayment placement
D) Extra ridge caps for added protection
D) Extra ridge caps for added protection
Wind-Driven Rain Vulnerabilities
Q: How can ridge flashing be vulnerable to wind-driven rain?
A) Poor underlayment placement
B) Excessive use of mortar
C) Using oversized ridge caps
D) Installing extra nails
A) Poor underlayment placement
Valley Weakness
Q: Why are valleys considered weak points in roofing systems?
A) They have a greater slope than adjacent roof planes
B) They direct water away from the roof
C) They have a lesser slope and erode faster
D) They are reinforced with extra layers of shingles
C) They have a lesser slope and erode faster
Valley Types
Q: What are the two main types of roof valleys?
A) Open and closed
B) Steep and flat
C) Sealed and unsealed
D) Single and double
A) Open and closed
Open Valleys
Q: What is a defining characteristic of an open valley?
A) Flashing material is hidden under shingles
B) Roof coverings overlap across the valley center
C) Flashing material is visible
D) Only used on asphalt shingle roofs
C) Flashing material is visible
Closed Valleys
Q: What is a defining characteristic of a closed valley?
A) Flashing material is visible
B) Roof plane material extends across the valley
C) Only used on tile roofs
D) Requires no additional protection
B) Roof plane material extends across the valley ✅
Valley Flashing Materials
Q: Which of the following is NOT a common valley flashing material?
A) Roofing felt
B) Roll roofing
C) Plywood
D) Metal (galvanized steel, copper, lead, etc.)
C) Plywood
Open Valleys on Asphalt Shingle Roofs
Q: How should an open valley be formed on an asphalt shingle roof?
A) With a single layer of ice and water shield
B) With two layers of roll roofing and metal flashing
C) With a single layer of roll roofing
D) With shingles overlapping across the valley
B) With two layers of roll roofing and metal flashing
Open Valley Metal Flashing Requirements
Q: What is the minimum width for metal flashing in an open valley?
A) 12 inches
B) 18 inches
C) 24 inches
D) 36 inches
C) 24 inches
Ridge Height in Metal Valley Flashing
Q: How high should the center rib of metal valley flashing be?
A) ¼ inch
B) ½ inch
C) 1 inch
D) 2 inches
C) 1 inch
Fully Closed Valley Definition
Q: What defines a fully closed valley?
A) Shingles from both planes interwoven across the valley
B) Flashing material is visible in the center
C) Shingles cut back 3 inches from the centerline
D) Only used on metal roofs
A) Shingles from both planes interwoven across the valley
Closed-Cut Valley Definition
Q: What defines a closed-cut valley?
A) Shingles from one plane cross over the other, with the top layer cut back 2 inches
B) Shingles from both planes are interwoven
C) No underlayment protection is needed
D) Shingles extend exactly to the valley centerline
A) Shingles from one plane cross over the other, with the top layer cut back 2 inches
Valley Underlayment Protection
Q: What additional protection should be applied under shingles in a valley?
A) One layer of 36-inch roofing felt
B) One layer of ice and water shield
C) No additional protection is needed
D) Tar is applied instead of underlayment
A) One layer of 36-inch roofing felt
B) One layer of ice and water shield
(Both A and B are correct, depending on the application.)
Nailing Guidelines for Shingles in Valleys
Q: How close to the valley centerline should nails be placed?
A) No closer than 3 inches
B) No closer than 6 inches
C) No closer than 9 inches
D) Anywhere as long as they are sealed
B) No closer than 6 inches
Shingle Cementing in Valleys
Q: What should be done to the un-nailed portions of shingles in valleys?
A) They should be stapled down
B) They should be left loose for flexibility
C) They should be cemented down
D) They should be overlapped with tar paper
C) They should be cemented down
Question: Why is flashing required at the junction where two roofs with different slopes meet?
A) To support the weight of the roof
B) To prevent water from leaking into the structure
C) To provide a decorative feature
D) To improve roof aesthetics
Answer: B) To prevent water from leaking into the structure
What is commonly seen where the roof slope changes, especially when a house has an addition?
A) Different roofing materials on the two roof planes
B) The same roofing material on both planes
C) No flashing required
D) Only shingles on both roof planes
Answer: A) Different roofing materials on the two roof planes
How far should the material of the lower-slope roof extend under the covering of the conventional-slope roof in most cases?
A) 1 inch
B) 12 inches
C) 1 foot
D) 3 feet
Answer: B) 12 inches
Question: In areas with high snow loads, how much should the lower-slope roof material be extended under the conventional roof covering?
A) 1 foot
B) 12 inches
C) 3 feet
D) No extension required
Answer: C) 3 feet
What should an inspector look for at the junction of two roof planes with the same roofing material?
A) Extra ventilation
B) An extra layer of roofing felt or an impermeable membrane
C) A second layer of shingles
D) No inspection needed
Answer: B) An extra layer of roofing felt or an impermeable membrane
Which of the following is a common indicator of moisture intrusion in an attic space?
A) Rusted nails in the roofing material
B) Water staining or discoloration on the ceiling or walls
C) Cracked roof tiles or shingles
D) Abnormal attic insulation levels
Answer: B) Water staining or discoloration on the ceiling or walls
According to the Florida Building Code, what is the minimum slope required for a roof covered with asphalt shingles?
A) 1:12
B) 2:12
C) 3:12
D) 4:12
Answer: D) 4:12
During a roof inspection, you observe that the asphalt shingles are beginning to curl at the edges. What does this likely indicate?
A) The shingles have reached the end of their useful life
B) The roof has been recently installed
C) The roof is improperly ventilated
D) The shingles were installed too loosely
Answer: A) The shingles have reached the end of their useful life
What is a common cause of condensation in an attic with inadequate ventilation?
A) Excessive use of air conditioning
B) High indoor humidity levels
C) Insufficient insulation
D) Prolonged exposure to sunlight
Answer: B) High indoor humidity levels
You observe that the roof deck is sagging between the rafters. What is the most likely cause of this condition?
A) Excessive load from snow or accumulated debris
B) Natural aging of the roofing material
C) Improper roof ventilation
D) Incorrect shingle installation
Answer: A) Excessive load from snow or accumulated debris
When inspecting roof flashings, which of the following should an inspector be most concerned about?
A) Visible rust or corrosion
B) Minor damage to shingles
C) The presence of additional roofing layers
D) Uneven spacing between roofing materials
Answer: A) Visible rust or corrosion
Question: Which roofing material is commonly used on flat or low-slope roofs?
A) Asphalt shingles
B) Roll roofing
C) Clay tiles
D) Wood shakes
Answer: B) Roll roofing
What are the two primary types of flashings used at the roof-wall interface?
A) Step flashing and counter-flashing
B) Base flashing and counter-flashing
C) Ridge flashing and base flashing
D) Drip edge flashing and valley flashing
Answer: B) Base flashing and counter-flashing
In some cases, the siding can serve as which type of flashing?
A) Base flashing
B) Cap flashing
C) Counter-flashing
D) Valley flashing
Answer: C) Counter-flashing
What is the typical clearance that should be maintained between siding and base flashing to prevent water from wicking into the siding?
A) 1 to 2 inches
B) 3 to 4 inches
C) 5 to 6 inches
D) 1/2 inch
Answer: A) 1 to 2 inches
Which material is still commonly used for flashing against masonry due to its malleability and ability to retain its shape?
A) Copper
B) Aluminum
C) Lead
D) Galvanized steel
Answer: C) Lead
What is the minimum height and width that base flashing installed against a vertical wall must be?
A) 2 inches high by 2 inches wide
B) 3 inches high by 3 inches wide
C) 4 inches high by 4 inches wide
D) 5 inches high by 5 inches wide
Answer: C) 4 inches high by 4 inches wide
In tile roof installations, what type of flashing is typically installed before the tiles are laid down?
A) Continuous flashing
B) Pan flashing
C) Step flashing
D) Kickout flashing
Answer: B) Pan flashing
What is one of the major problems with tile roofs related to flashing?
A) Flashing being incompatible with roof materials
B) Tiles outlasting the flashing
C) Flashing causing water retention
D) Flashing cracking due to extreme heat
Answer: B) Tiles outlasting the flashing
For continuous roof coverings like roll roofing or membrane, what often serves as the base flashing?
A) Step flashing
B) The roof covering itself
C) Counter-flashing
D) Kickout flashing
Answer: B) The roof covering itself
What is the purpose of kickout flashing?
A) To direct water away from the roof and into a gutter
B) To prevent water from running down the wall and into the wall system
C) To act as a base flashing on flat roofs
D) To prevent debris buildup at the roof-wall interface
Answer: B) To prevent water from running down the wall and into the wall system
Question: Which of the following is a type of flashing installed where the roof intersects a vertical sidewall?
A) Counter-flashing
B) Step flashing
C) Apron flashing
D) Cricket flashing
Answer: B) Step flashing
What is the primary purpose of counter-flashing?
A) To protect the top edges of other flashings to prevent water intrusion
B) To divert water around a chimney
C) To seal the base of the chimney to prevent leaks
D) To act as a decorative feature at the roofline
Answer: A) To protect the top edges of other flashings to prevent water intrusion
Where is apron flashing typically installed?
A) Where a roof intersects a vertical wall
B) Where a roof intersects a headwall, such as at a dormer or chimney
C) At the base of the roof
D) Where a roof transitions from a steep slope to a flat slope
Answer: B) Where a roof intersects a headwall, such as at a dormer or chimney
What is the purpose of cricket flashing?
A) To prevent water from flowing into the roof cavity
B) To direct water around a chimney or curbed roof penetration
C) To seal the edges of the chimney stack
D) To serve as a decorative border around a chimney
Answer: B) To direct water around a chimney or curbed roof penetration
When is backer flashing typically installed?
A) When a chimney is wider than 30 inches
B) When a chimney is narrow (about 20 inches wide) and does not require a cricket
C) Only on masonry chimneys
D) Only on steep-slope roofs
Answer: B) When a chimney is narrow (about 20 inches wide) and does not require a cricket
What is the recommended best practice for installing counter-flashing at a masonry chimney stack?
A) Insert the flashing material at least 1 inch into the masonry joint
B) Install the flashing material directly on top of the chimney stack
C) Install the counter-flashing 4 inches above the chimney
D) Install the flashing only around the chimney base
Answer: A) Insert the flashing material at least 1 inch into the masonry joint
What is a common problem when counter-flashing is missing at a chimney sidewall?
A) Water penetration at the top edge of the step flashing
B) Excessive water runoff down the chimney
C) Chimney cap damage
D) Cracked masonry
Answer: A) Water penetration at the top edge of the step flashing
What defect was identified with the cricket flashing installed on the backside of a masonry chimney stack covered with stucco?
This is a cricket installed on the backside of a masonry chimney stack covered with a stucco exterior covering. The valley on the left side of the cricket has been sealed up with black roofing sealant. This is an indication of a water intrusion problem. The sealant is not permanent. Poor practice. Defect.
A) The cricket was too small
B) The valley was sealed with black roofing sealant, indicating potential water intrusion
C) The cricket was missing entirely
D) The flashing was incorrectly installed
Answer: B) The valley was sealed with black roofing sealant, indicating potential water intrusion
What is the problem with missing cricket flashing on a large chimney stack (about 4 feet wide)?
A) It creates a risk of water infiltration due to the lack of proper water diversion
B) It causes the chimney to collapse under heavy rainfall
C) It leads to excessive heat buildup in the chimney
D) It prevents proper venting of the chimney
Answer: A) It creates a risk of water infiltration due to the lack of proper water diversion
