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NCCER Roofing practice questions

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Question 1Roofing

What is the minimum slope, in roofing squares terminology, at which a built-up roof using asphalt-impregnated organic felt plies is generally considered a steep-slope application requiring different detailing?

  1. 2:12
  2. 3:12
  3. 1:12
  4. 4:12 Correct answer.

Explanation

Roof slopes are expressed as inches of rise per 12 inches of run. A rise of 4 inches per foot is the conventional dividing line between low-slope and steep-slope roofing practice, so 4:12 is the threshold. Below that, low-slope membrane and built-up systems apply.

Question 2Roofing

A roofing crew is installing underlayment beneath asphalt shingles on a roof with a 5:12 slope. Which underlayment practice is standard for this condition?

  1. A single layer of No. 30 felt laid dry with no laps
  2. One layer of a manufacturer-approved synthetic underlayment installed with the required laps Correct answer.
  3. Two layers of No. 15 felt lapped 19 inches are required at this slope
  4. No underlayment because the slope exceeds 4:12

Explanation

At a 5:12 slope, a single layer of approved synthetic underlayment is a standard option when installed according to applicable code and product instructions. Properly lapped No. 15 felt may also be used as a single layer. A 5:12 slope alone does not trigger the conventional double-layer felt requirement for low slopes.

Question 3Roofing

During a steep-slope asphalt shingle installation, what is the purpose of the starter course along the eave?

  1. To cover the exposed fasteners of the first full shingle course
  2. To provide a double layer of shingles at the eave and seal the first course against wind uplift and water backup Correct answer.
  3. To serve as the drip edge flashing
  4. To bridge the gap between the roof deck and the fascia

Explanation

A starter course is a shingle strip laid upside down or a dedicated starter product along the eave. It doubles the shingle thickness at the edge and provides a factory sealant strip for the first course, improving wind resistance and shedding water at the eave.

Question 4Roofing

A roofer is nailing asphalt shingles on a roof with a 6:12 slope. Which fastener pattern is conventional for a standard three-tab shingle?

  1. Six nails per shingle driven through the sealant strip
  2. Four nails per shingle placed in the nail zone just above the sealant strip Correct answer.
  3. Two nails per shingle placed above the sealant strip
  4. Staples driven at the top edge of each shingle

Explanation

Standard practice is four nails per three-tab shingle positioned in the manufacturer's nail zone above the sealant strip. Nails must penetrate the deck and not be overdriven, and staples or nails driven through the sealant strip compromise the seal.

Question 5Roofing

What is the primary function of a cricket on a roof?

  1. To anchor the gutter to the fascia
  2. To support the ridge board at the peak
  3. To divert water around a chimney or other large penetration Correct answer.
  4. To provide a vent path at the ridge

Explanation

A cricket is a small peaked roof built on the uphill side of a chimney or similar wide obstruction. It sheds water around the obstruction to prevent ponding and leaks at the roof-to-wall junction.

Question 6Roofing

A roofer is flashing a brick chimney on a composition shingle roof. Which component is installed on the roof side to shed water over the shingles?

  1. An apron flashing at the base of the chimney Correct answer.
  2. A backer flashing on the high side
  3. A step flashing woven into each shingle course
  4. A counterflashing embedded in the brick

Explanation

The apron flashing (also called base flashing) is installed at the low side of the chimney and laps over the shingles to shed water. Counterflashing is set into the masonry above it, and step flashing handles the sloped sides.

Question 7Roofing

Which type of valley flashing method is commonly used with asphalt shingles and involves shingles from one roof plane being woven over those of the other plane?

  1. Woven valley Correct answer.
  2. Closed cut valley
  3. Open metal valley
  4. California valley

Explanation

In a woven valley, shingles from alternating roof planes are interlaced over each other down the valley center. A closed-cut valley cuts one plane along the valley line, and an open valley exposes metal flashing through the center.

Question 8Roofing

What is the main purpose of roof sheathing?

  1. To insulate the attic space
  2. To carry the roof load to the foundation
  3. To provide a nailable surface that spans rafters and supports roof covering loads Correct answer.
  4. To vent moisture from the attic

Explanation

Roof sheathing (decking) spans across rafters or trusses and provides a solid nailable base for the roof covering. It distributes loads to the framing and stiffens the roof structure.

Question 9Roofing

A crew is installing drip edge on a gable roof. Where should the eave drip edge be placed relative to the underlayment?

  1. Between the sheathing and the underlayment at the rake
  2. Over the shingles at the eave
  3. Under the underlayment at the eave Correct answer.
  4. Over the underlayment at the eave

Explanation

At the eave, the drip edge is installed under the underlayment so water that reaches the underlayment drains over the metal edge. At the rake, drip edge typically goes over the underlayment to shed water away from the edge.

Question 10Roofing

What is the purpose of a ridge vent in a roof assembly?

  1. To allow intake air into the attic at the eave
  2. To seal the ridge against rain entry
  3. To allow hot, moist air to escape from the attic at the roof peak Correct answer.
  4. To provide a mounting point for the ridge board

Explanation

A ridge vent is an exhaust vent that allows hot, moist air to leave the attic at the highest point of the roof. It works with eave or soffit intake vents to create continuous airflow.

Question 11Roofing

A roofer is installing a skylight on a shingle roof. Which flashing detail is required on the uphill side of the skylight curb?

  1. A cricket or backer flashing to divert water around the curb Correct answer.
  2. A single layer of underlayment
  3. A counterflashing attached to the glass
  4. Only a bead of sealant along the curb

Explanation

On the uphill side of a skylight curb, a cricket or backer flashing sheds water around the obstruction and prevents it from pooling against the curb. Sealant alone is not a substitute for proper flashing.

Question 12Roofing

Which roofing term describes the horizontal distance a roof surface covers from the eave to the ridge measured along the slope?

  1. Rake
  2. Span
  3. Rise Correct answer.
  4. Run

Explanation

In roof geometry, rise is the vertical distance from eave to ridge, run is the horizontal distance, and span is the total horizontal distance across the building. The sloped length along the roof surface is sometimes called the slope length or rafter length.

Question 13Roofing

A roofing crew is installing a low-slope built-up roof and needs to determine the number of plies. What does a "four-ply" built-up roof mean?

  1. Four inches of insulation
  2. Four layers of roofing felt or ply sheets mopped together with bitumen Correct answer.
  3. Four coats of reflective coating
  4. Four separate membrane sheets laid side by side

Explanation

In built-up roofing, a ply is one layer of felt or ply sheet embedded in bitumen. A four-ply system means four such layers mopped together, topped with a surfacing, to build the membrane thickness.

Question 14Roofing

Which type of roofing underlayment is typically required under standing-seam metal roofing on a slope of 3:12 or steeper?

  1. Ordinary No. 15 felt only
  2. A high-temperature synthetic underlayment or No. 30 felt Correct answer.
  3. A vapor barrier such as polyethylene
  4. No underlayment at all

Explanation

Standing-seam metal roofs on slopes of 3:12 and steeper generally require a high-temperature synthetic underlayment or No. 30 felt to protect against condensation and to provide a secondary water barrier. Standard No. 15 felt is not sufficient for most metal roof specifications.

Question 15Roofing

What is the purpose of a kick-out flashing at the bottom of a roof-to-wall intersection?

  1. To seal the wall-to-roof gap with sealant
  2. To anchor the wall cladding to the roof
  3. To cover the exposed ends of step flashing
  4. To divert water away from the wall and into the gutter or roof surface Correct answer.

Explanation

Kick-out flashing is installed at the bottom of a step-flashed wall intersection to direct water out and away from the siding and into the gutter. Without it, water runs down the wall and can cause rot.

Question 16Roofing

A roofer is installing asphalt shingles in a high-wind zone. Which practice improves wind uplift resistance?

  1. Nailing above the sealant strip to allow shingle movement
  2. Using six nails per shingle in the nail zone and applying a bead of asphalt roof cement along the sealant strip Correct answer.
  3. Installing shingles with a wider exposure than the manufacturer specifies
  4. Using two nails per shingle to avoid splitting the shingle

Explanation

In high-wind areas, manufacturers often require six nails per shingle placed in the nail zone, and sealant strips must bond properly. Adding roof cement along the sealant strip helps the shingles seal down against uplift.

Question 17Roofing

What is the minimum recommended clearance between the bottom of an asphalt shingle roof edge and the ground or roof below at a wall intersection?

  1. 2 inches Correct answer.
  2. 6 inches
  3. 1 inch
  4. 4 inches

Explanation

Roofing practice generally calls for a minimum 2-inch clearance between the bottom of the shingle roof edge and the surface below at a wall or roof-to-roof intersection. This keeps water from backing up and allows proper flashing.

Question 18Roofing

A roofing contractor is estimating materials for a gable roof with a 6:12 slope measuring 30 feet wide by 40 feet long. What is the approximate slope length of each roof plane from eave to ridge?

  1. 15 feet
  2. 18 feet Correct answer.
  3. 20 feet
  4. 24 feet

Explanation

The run of each plane is half the 30-foot width, or 15 feet. With a 6:12 slope, the slope factor is about 1.118, so the slope length is 15 × 1.118 ≈ 16.8 feet, or about 18 feet when rounded for estimating.

Question 19Roofing

Which fastening method is appropriate for attaching wood shingles or shakes to a roof deck?

  1. Galvanized or stainless steel roofing nails driven through the shingle into the deck Correct answer.
  2. Staples driven at the top edge
  3. Screws driven through the exposure
  4. Construction adhesive alone

Explanation

Wood shingles and shakes are fastened with corrosion-resistant nails, typically galvanized or stainless steel, driven through the shingle into the deck. Nails should be placed so they do not split the wood and should be driven flush, not overdriven.

Question 20Roofing

What is the purpose of a fascia board on a roof?

  1. To vent the attic at the ridge
  2. To span between rafters and carry the ceiling load
  3. To support the roof sheathing at the ridge
  4. To provide a finished edge and a mounting surface for the gutter at the eave Correct answer.

Explanation

The fascia is the board attached to the ends of the rafters or trusses at the eave. It provides a finished edge, supports the gutter, and closes off the rafter ends.

Question 21Roofing

A roofer is repairing a leak around a plumbing vent pipe. Which flashing component is installed over the pipe and lapped over the shingles?

  1. A cricket
  2. A step flashing
  3. A counterflashing
  4. A vent-pipe boot or flange flashing Correct answer.

Explanation

A vent-pipe boot, also called a flange flashing, slides over the pipe and has a wide flange that laps over the shingles. The upper portion is covered by the next shingle course to shed water.

Question 22Roofing

Which of the following best describes the installation of a closed-cut valley with asphalt shingles?

  1. Shingles from both roof planes are woven together down the valley center
  2. Shingles from one plane are extended across the valley uncut, with the other plane's shingles laid over them and trimmed to the manufacturer's specified offset line Correct answer.
  3. Metal flashing is left exposed down the valley center
  4. Shingles are cut back six inches from the valley center on both planes

Explanation

In a closed-cut valley, shingles from the first roof plane extend across the valley uncut. Shingles from the second plane overlap them and are trimmed along the manufacturer's specified line, offset from the valley center. The underlying shingles remain continuous beneath the trimmed, overlapping layer.

Question 23Roofing

What is the purpose of sealing the ridge cap on an asphalt shingle roof?

  1. To cover the ridge intersection and prevent water entry Correct answer.
  2. To provide a nailing surface for the fascia
  3. To allow air to escape from the attic
  4. To anchor the ridge board to the rafters

Explanation

Ridge cap shingles cover the intersection of the two roof planes at the peak. They overlap and seal to prevent water from entering at the ridge, and they must be fastened and sealed according to the manufacturer's instructions.

Question 24Roofing

A roofing crew is installing a low-slope modified bitumen membrane. Which application method uses a torch to heat the membrane underside and the substrate?

  1. Cold-applied adhesive
  2. Hot-mopped
  3. Self-adhered
  4. Torch-applied Correct answer.

Explanation

Torch-applied modified bitumen uses a propane torch to heat the membrane underside and the substrate so the bitumen bonds. It requires fire precautions and trained installers. Cold-applied, self-adhered, and hot-mopped are separate application methods.

Question 25Roofing

Which condition most likely indicates that roof sheathing is too thin or deteriorated for a new shingle installation?

  1. The sheathing deflects noticeably when walked on and fasteners do not hold Correct answer.
  2. The sheathing has visible gaps of 1/8 inch between panels
  3. The sheathing is stamped with a grade mark
  4. The sheathing is covered with a layer of underlayment

Explanation

Deflection under foot traffic and fasteners that will not hold indicate the sheathing lacks adequate thickness or has deteriorated. In that case, the deck should be repaired or replaced before installing new roofing.

Question 26Roofing

A roofing crew is installing a low-slope built-up roof and must place the base sheet. Which material is commonly used as the base ply directly on the roof deck?

  1. A perforated asphalt-saturated felt or a venting base sheet Correct answer.
  2. A granule-surfaced cap sheet
  3. A polyethylene vapor retarder
  4. A layer of gravel embedded in hot asphalt

Explanation

The base ply of a built-up roof is typically a saturated felt or a purpose-made venting base sheet fastened to the deck. It provides the foundation for subsequent plies and allows moisture vapor to escape. Granule-surfaced cap sheets and gravel are finishing layers, not base plies.

Question 27Roofing

A roofer is installing underlayment beneath asphalt shingles on a steep-slope roof. Why is a single layer of No. 15 asphalt-saturated felt commonly used?

  1. To provide a secondary weather barrier if shingles are blown off or damaged Correct answer.
  2. To add structural stiffness to the roof deck
  3. To insulate the roof surface
  4. To bond the shingles to the sheathing

Explanation

Underlayment acts as a backup weather barrier that sheds water if shingles are displaced or a small leak develops. It is not a structural or insulating component. Its role is moisture protection, not adhesion or stiffness.

Question 28Roofing

A roofing crew is nailing asphalt shingles on a steep-slope roof. Where should the nails be placed on a standard three-tab shingle?

  1. Through the center of each tab at the butt edge
  2. Below the adhesive strip, near the butt edge
  3. In the nail zone just above the cutouts and below the adhesive strip Correct answer.
  4. Above the nail line, through the exposed area of the shingle

Explanation

Fasteners must penetrate the nail zone located above the cutouts and below the self-sealing adhesive strip. This location secures the shingle without interfering with tab sealing and keeps nails covered by the overlapping course. Nailing outside this zone causes leaks or poor sealing.

Question 29Roofing

What is the purpose of installing a metal drip edge along the eave of a shingle roof?

  1. To direct water away from the fascia and deck edge Correct answer.
  2. To provide ventilation at the eave
  3. To support the weight of the shingles at the overhang
  4. To anchor the gutter to the roof

Explanation

Drip edge at the eave sheds water clear of the fascia and deck edge so it does not wick back into the structure. It also helps protect the edge of the underlayment. It is not a structural support or ventilation device.

Question 30Roofing

A roofer is installing step flashing along a sidewall where a sloped roof meets a vertical wall. How should each piece of step flashing be positioned?

  1. Lapped over the shingle above and under the shingle below Correct answer.
  2. Laid flat on top of the shingles without a vertical leg
  3. Installed continuously in one long piece under the siding
  4. Placed only at the bottom of the wall

Explanation

Step flashing is installed in individual pieces that weave with the shingle courses. Each piece laps over the shingle course below it and is covered by the next course, with a vertical leg against the wall. This shingle-and-flashing interlock keeps water from entering at the wall.

Question 31Roofing

A roofing crew is installing wood shakes and must space them properly. What is the purpose of the gaps between adjacent shakes?

  1. To provide attachment points for the next course
  2. To let air circulate through the deck
  3. To reduce the total number of shakes needed
  4. To allow the shakes to expand and contract and to permit drainage Correct answer.

Explanation

Wood shakes swell when wet, so a small gap between edges prevents buckling and allows water to drain. Without spacing, the shakes can split or push each other out of alignment. The spacing is a movement and drainage allowance.

Question 32Roofing

Which statement best describes the slope range that is generally considered low-slope roofing?

  1. A slope of 2:12 or less, often called flat roofing Correct answer.
  2. A slope between 6:12 and 12:12
  3. A slope of 4:12 or steeper
  4. A slope of exactly 1:12

Explanation

Low-slope roofing is generally defined as slopes of 2:12 or less, which includes what the trade calls flat roofs. These roofs use membrane or built-up systems rather than standard shingles. Steep-slope roofing begins above that threshold.

Question 33Roofing

A roofer is installing a ridge cap on an asphalt shingle roof. Why is the ridge cap important?

  1. It anchors the roof to the walls
  2. It supports the ends of the rafters
  3. It provides the primary ventilation for the attic
  4. It covers the gap at the ridge and protects against water entry Correct answer.

Explanation

Ridge cap shingles cover the open joint where the two roof planes meet at the ridge and prevent water from entering. They are a weatherproofing detail, not a structural or ventilation component. Ventilation at the ridge requires a separate vent.

Question 34Roofing

A roofing crew is installing a single-ply EPDM membrane on a low-slope roof. How are the seams typically joined?

  1. By stapling the laps together
  2. By heat-welding with a hot-air gun
  3. By nailing through the lap with capped fasteners
  4. By applying a splice adhesive or splice tape between the laps Correct answer.

Explanation

EPDM is a thermoset rubber that cannot be heat-welded, so seams are joined with contact adhesive or splice tape. The lap surfaces are cleaned and pressed together to form a watertight bond. Heat welding is used for thermoplastic membranes such as TPO and PVC.

Question 35Roofing

A roofer is installing a TPO membrane and needs to join the laps. Which method is appropriate?

  1. Mechanical crimping
  2. Peel-and-stick butyl tape only
  3. Hot-air or hot-wedge welding Correct answer.
  4. Solvent-based contact cement

Explanation

TPO is a thermoplastic membrane, so laps are fused by hot-air or hot-wedge welding to create a monolithic seam. The weld is typically tested with a probe for seam integrity. Adhesives and tape are not the primary seam method for TPO.

Question 36Roofing

A roofing contractor is installing a steep-slope roof with a 9:12 pitch. What fall-protection measure is generally required for workers exposed to the roof edge?

  1. No protection if the roof is under 20 feet high
  2. Warning lines only, with no other protection
  3. A spotter standing at the eave
  4. A personal fall-arrest system, guardrail, or safety net Correct answer.

Explanation

At slopes of 4:12 and steeper, OSHA requires conventional fall protection such as guardrails, safety nets, or personal fall-arrest systems. Warning lines alone are permitted only on low-slope roofs. Height and spotters do not substitute for required protection.

Question 37Roofing

A crew is installing a built-up roof and must apply the flood coat. What is the purpose of the flood coat?

  1. To embed the surfacing and seal the plies Correct answer.
  2. To serve as the vapor retarder
  3. To provide a slip sheet between plies
  4. To bond the base sheet to the deck

Explanation

The flood coat is the final heavy application of bitumen that saturates and seals the plies and receives the gravel or mineral surfacing. It is the top weatherproofing layer of the membrane. Base bonding and vapor control occur in lower layers.

Question 38Roofing

A roofer is installing a cricket on a roof where a chimney wider than 30 inches penetrates the slope. What is the function of the cricket?

  1. To anchor the chimney flashing to the roof
  2. To divert water around the chimney and prevent ponding Correct answer.
  3. To support the chimney above the roof deck
  4. To provide a vent for the chimney flue

Explanation

A cricket is a small sloped framing member built on the uphill side of a wide chimney to shed water around it. Without a cricket, water can collect against the chimney and leak. It is a drainage detail, not structural support or venting.

Question 39Roofing

A roofing crew is installing a skylight on a low-slope membrane roof. Which detail is essential on the uphill side of the curb?

  1. A backer or cricket to divert water around the curb Correct answer.
  2. A nailer for shingles on top of the curb
  3. A layer of gravel around the curb
  4. A vent opening in the curb

Explanation

On low-slope roofs, water moving down the roof can pond against the uphill side of a skylight curb. A backer or cricket diverts water around the curb and prevents leakage. Gravel, vents, and shingle nailers do not address this drainage problem.

Question 40Roofing

A roofer is installing a plumbing vent through a shingle roof. Which component seals the penetration at the roof surface?

  1. A lead or rubber boot flashing with a collar around the pipe Correct answer.
  2. A ridge vent
  3. A drip edge
  4. A cricket

Explanation

A vent boot flashing has a collar that fits tightly around the pipe and a flanged base that is integrated with the shingles. This seals the penetration against water entry. Ridge vents, drip edge, and crickets serve different purposes.

Question 41Roofing

A roofing crew is installing a modified bitumen membrane using the torch-applied method. Which safety precaution is most critical during this work?

  1. Removing all roof vents before torching
  2. Wetting the membrane before heating
  3. Keeping a fire extinguisher nearby and maintaining a fire watch Correct answer.
  4. Wearing rubber gloves only

Explanation

Torch application uses an open flame, so fire extinguishers, a fire watch, and clearance from combustibles are essential. The membrane and substrate must be dry, not wet. Gloves alone are not adequate protection against fire risk.

Question 42Roofing

A roofer is installing a metal roof with standing seams on a 4:12 slope. Which fastening approach is typical for the panels?

  1. Adhering the panels with construction adhesive
  2. Through-fastening the panels at every seam with exposed screws
  3. Concealed clips fastened to the deck that allow the panels to move Correct answer.
  4. Nailing the panels through the standing seams

Explanation

Standing-seam metal panels are held by concealed clips that permit thermal movement while securing the panel. Exposed fasteners through the panel surface are used on through-fastened panels, not standing-seam systems. Adhesive and nails do not provide the required concealed attachment.

Question 43Roofing

A roofing crew is installing a low-slope roof and must install insulation. Which insulation board type is commonly used on low-slope commercial roofs?

  1. Polyisocyanurate board Correct answer.
  2. Spray foam only
  3. Loose-fill cellulose
  4. Fiberglass batt insulation

Explanation

Polyisocyanurate rigid board is a common low-slope roof insulation because it provides high R-value and a stable surface for the membrane. Batts and loose-fill are used in cavities, not as roof boards. Spray foam is used in some systems but is not the standard board option.

Question 44Roofing

A roofer is installing a valley on a shingle roof where the valley is woven with shingles from both planes. Which statement describes an open valley?

  1. The valley is covered with a metal pan only
  2. Shingles are laid parallel to the valley center line
  3. Shingles from one plane are extended across the valley and cut along the other plane
  4. The valley lining is left exposed with shingles trimmed back from the center line Correct answer.

Explanation

An open valley leaves the metal or membrane lining visible along the center, with shingles trimmed back on each side. A woven or closed-cut valley covers the lining with shingles. Metal pans alone are not the definition of an open valley.

Question 45Roofing

A roofing contractor is preparing to install a new shingle roof over an existing deck. Which condition indicates the deck is unsuitable for new shingles?

  1. The sheathing sags noticeably between rafters and feels soft underfoot Correct answer.
  2. The sheathing has minor surface staining
  3. The sheathing is clean and dry
  4. The sheathing has a few loose nails that can be reset

Explanation

Soft, sagging sheathing indicates deterioration or inadequate thickness and will not hold fasteners or support the new roof. Loose nails, surface cleanliness, and minor staining are normal conditions that can be corrected. The deck must be structurally sound before re-roofing.

Question 46Roofing

A roofer is installing a low-slope roof and must install a vapor retarder. Where should it be placed in the assembly?

  1. Below the structural deck, exposed to the interior
  2. On top of the membrane
  3. Between the insulation and the membrane
  4. On the warm side of the insulation, near the interior ceiling Correct answer.

Explanation

A vapor retarder is placed on the warm side of the insulation to prevent interior moisture from entering the roof assembly. In a typical low-slope roof, this is near the deck or ceiling below the insulation. Placing it above the insulation or membrane would trap moisture.

Question 47Roofing

A roofing crew is installing a built-up roof and must determine the number of plies. What does a four-ply BUR system provide compared with a three-ply system?

  1. Elimination of the need for a flood coat
  2. A lighter overall roof weight
  3. Greater redundancy and durability against weather and foot traffic Correct answer.
  4. Reduced need for a base sheet

Explanation

Additional plies increase the membrane's redundancy and resistance to weathering and foot traffic. More plies add weight rather than reduce it. A flood coat and base sheet are still required regardless of ply count.

Question 48Roofing

A roofer is installing a metal roof on a roof with a slope of 2:12. Which detail is critical to prevent water infiltration at the panel laps?

  1. Using only nails at the panel centers
  2. Installing panels with no overlap
  3. Proper lap width and sealant at the side and end laps Correct answer.
  4. Removing all sealant to allow drainage

Explanation

At low slopes, water moves slowly and can be driven under laps, so adequate lap width and sealant are critical. Panels must overlap, and sealant helps seal the laps. Removing sealant or omitting overlap would allow leaks.

Question 49Roofing

A roofing crew is installing a steep-slope roof and must install underlayment on a 3:12 slope. What is the minimum underlayment requirement for asphalt shingles at this slope?

  1. Underlayment is required only at the eaves
  2. No underlayment is required
  3. A double layer of underlayment lapped and fastened per code Correct answer.
  4. A single layer of underlayment only

Explanation

On slopes below 4:12, asphalt shingles require a double layer of underlayment to provide adequate backup protection. A single layer is permitted only on steeper slopes. Omitting underlayment or limiting it to the eaves would not meet the requirement.

Question 50Roofing

A roofer is evaluating an existing roof for a re-roof and finds that the existing shingles are brittle and the deck has multiple soft spots. What is the most appropriate course of action?

  1. Install new shingles directly over the existing roof
  2. Apply a coating to the existing shingles and leave them in place
  3. Patch only the soft spots and install new shingles
  4. Remove the existing roofing and repair or replace the deteriorated deck before installing new shingles Correct answer.

Explanation

Soft spots indicate deck deterioration that must be repaired before a new roof can be installed. Brittle shingles and a compromised deck mean the existing roof is not a suitable substrate. Covering or coating would not correct the structural problem.