Exam Cheat Sheet · Quick Reference
Alabama Roofing and Sheet Metal Contractor
Alabama · PSI Services Contractor
Verified, not estimated. Every figure below is drawn from the official exam structure we maintain — question counts, passing standard and topic weighting. Practice questions are grounded in the source law with statute citations. We omit any figure we can't verify rather than guess at it.
Total questions
60
Passing score
70%
Exam time
150 min
Administered by
PSI Services Contractor
Format
Reference materials allowed
Alabama State Portion 60 questions
Estimating and Plan Reading
10 Q · 17%
Measuring roof area using positive and negative methodsRoof slope calculation and conversion (rise/run, pitch, degrees)Roof-slope factors and rafter length calculation from plan dimensionsCalculating net versus gross roof area and allowance factorsHip and valley length determination using slope factors and appendix tablesLabor unit price calculation and adjusting for actual crew wagesProduction rate formulas and project duration estimationArea modification factors and use of published estimating guides
Surface Preparation and Planning
8 Q · 13%
Roof deck inspection and pre-installation requirementsWood panel (plywood and OSB) deck selection, grading standards, and minimum thickness requirementsStructural load-bearing capacity and deflection limitations for roof decksRoof slope and drainage requirements including minimum slope standards by system typeUnderlayment types, selection criteria, and installation requirements by roof covering and slopeAir and vapor retarder design and placement within roof assembliesRigid board insulation types, R-values, multilayer installation, and cover board requirementsDeck surface condition, moisture control, and treatment considerations for preservative- and fire-retardant-treated panels
Steep and Low Slope Roofing, including BUR, Waterproofing
27 Q · 45%
Asphalt shingle materials, types, and installation requirementsBuilt-up roofing (BUR) composition, bitumens, and surfacing typesSingle-ply membrane systems (EPDM, TPO, PVC) attachment methodsPolymer-modified bitumen (APP and SBS) membrane systemsUnderlayment types, configurations, and installation for steep-slope systemsClay, concrete tile, and slate roof system materials and installationWood shake and wood shingle grading, materials, and installationRoof insulation types, R-values, and thermal performance for low-slope assemblies
Roofing Components
9 Q · 15%
Roof deck and sheathing types (solid vs. spaced decking, plywood, board sheathing)Underlayment materials and classifications (asphalt felt, synthetic sheet, polymer-modified bitumen, self-adhering membranes)Underlayment application requirements by roof slope and covering typeIce barrier and water/ice-dam protection membrane requirementsFlashing types and installation (drip edge, valley, step, apron, counterflashing, crickets/saddles)Roof accessories (equipment curbs, expansion joint covers, prefabricated pipe flashings, roof vents, skylights, snow guards)Fire classification of roof assemblies (Class A, B, C) and wind resistance requirementsMembrane roof system surfacings (aggregate, ballast, coatings, vegetative)
Safety
6 Q · 10%
Fall protection requirements for roofing work (low-slope and steep roofs)Personal fall arrest systems — components, criteria, and inspectionGuardrail systems — specifications and installation requirementsScaffold safety — erection, use, fall protection, and falling object protectionLadder and stairway safety requirementsFire protection and prevention — extinguishers, flammable liquids, and fire prevention programsPersonal protective equipment — head, eye, face, foot, and hearing protectionGeneral safety and health provisions — employer responsibilities, safety training, and housekeeping
Key Distinctions
Wood shingles (naturally durable wood)vsWood shakes (naturally durable wood)
Wood shingles may be Grade 1, 2, or 3 under CSSB rules, while wood shakes require a minimum of Grade 1 (taper sawn shakes allow Grade 1 or 2).
IBC 2021 Table 1507.8.5Positive method of roof measurementvsNegative method of roof measurement
The positive method divides an irregular roof into rectangles and adds their areas, while the negative method extends roof lines into one large rectangle and subtracts the non-roof areas; both give identical results.
Roofing Construction and Estimating, Chapter 1, Pages 7-8Roof pitchvsRoof slope
Pitch is Total Rise divided by Total Span, while slope is rise in inches per 12 inches of run, and Slope = 2 × Pitch.
Roofing Construction and Estimating, Page 11ASTM D7158 wind classificationvsASTM D3161 wind classification
ASTM D7158 is a testing-and-calculation procedure using ASCE 7-22 building environment factors yielding basic-wind-speed classes (D=90 mph, G=120 mph, H=150 mph), whereas ASTM D3161 is a fan-induced wind test (Class A=60 mph, D=90 mph, F=110 mph).
NRCA Roofing Manual: Steep-slope Roof Systems (2025), Section 4.2—Wind Resistance (ASTM D7158—Calculation Basis)Nail penetration in wood plank/board decksvsNail penetration in plywood decks less than ¾ inch thick
In wood plank or board decks nails must penetrate at least ¾ inch into the deck, while in plywood or acceptable wood panel decks under ¾ inch thick nails must extend a minimum of ⅛ inch through the underside.
NRCA Roofing Manual: Steep-slope Roof Systems (2025), Section 4.2—Asphalt Shingle Roof System Design and Installation (Fasteners)Class A / Class B / Class C roof assembliesvsFire-test exposure level
Class A is effective against severe fire-test exposure, Class B against moderate exposure, and Class C against light exposure.
IBC 2021 Section 1505.2Cricket at upslope side of chimneyvsBacker flashing
NRCA recommends a cricket when the chimney or curbed penetration is more than 24 inches wide; backer flashing is generally limited to penetrations 24 inches wide or less.
NRCA Roofing Manual: Steep-slope Roof Systems (2025), Asphalt Shingle Roof Systems — Chapter 7ASHRAE 90.1 deemed-to-comply closed-cell spray foam air retardervsIECC deemed-to-comply closed-cell spray foam air retarder
ASHRAE 90.1 criteria are 2.0 lbs./ft.³ density and minimum 1 inch thick, while the IECC criteria are 1.5 lbs./ft.³ density and minimum 1½ inches thick.
NRCA Roofing Manual: Membrane Roof Systems (2023), Page 116Clay roof tile / slate standardsvsConcrete roof tile / asphalt shingle standards
Clay roof tile must comply with ASTM C1167 and slate with ASTM C406, whereas concrete roof tile must comply with ASTM C1492 and asphalt shingles with ASTM D3462.
IBC 2021 Section 1507.3.4Plywood sheathing over rafters 16 in. o.c.vsPlywood sheathing over rafters 24 in. o.c.
NRCA recommends minimum four-ply nominal ⅝-inch plywood (actual 19/32 in.) at 16-inch spacing and nominal ¾-inch plywood (actual 23/32 in.) at 24-inch spacing for asphalt shingle roofs.
NRCA Roofing Manual: Steep-slope Roof Systems (2025), Section 2.1—Wood PanelsSpaced sheathing for wood shakesvsSpaced sheathing for wood shingles
Shakes normally use 1 × 6 boards spaced equal to the shake weather exposure, while wood shingles typically use 1 × 4 boards.
Roofing Construction and Estimating, Page 30Scaffold fall-protection threshold (29 CFR Subpart L)vsGeneral walking/working surface threshold (Subpart M)
Employees on a scaffold must be protected from falling when more than 10 feet above a lower level, which differs from the general 6-foot threshold for other walking/working surfaces.
29 CFR 1926, §1926.451(g)(1)Self-adhering polymer-modified bitumen ice-dam membranesvsPolymer-modified bitumen base sheets (non-self-adhering)
Self-adhering water and ice-dam protection sheets typically range from 20 to 60 mils thick, while non-self-adhering PMB base sheets typically range from about 35 to 90 mils.
NRCA Roofing Manual: Steep-slope Roof Systems (2025), Section 3.1—Underlayment Materials (Self-adhering Polymer-modified Bitumen Sheets)Battens permitted on tile roofsvsBattens required on tile roofs
Battens may be installed on slopes of 2½ in 12 and steeper, but they are required on slopes of 7 in 12 and steeper.
Roofing Construction and Estimating, Chapter 7 — Tile RoofingKey Terms
Class A roof assembly IBC 2021 Section 1505.2
An assembly effective against severe fire-test exposure; examples include minimum 16 oz./sq. ft. copper sheets over combustible decks and slate over ASTM D226 Type II underlayment over combustible decks.
Fire classification test standards (ASTM E108 / UL 790) IBC 2021 Section 1505.1
Class A, B, and C roof assemblies and roof coverings required to be listed are tested in accordance with ASTM E108 or UL 790.
Full-cell vacuum-pressure process IBC 2021 Section 1505.6
The impregnation process, in accordance with AWPA C1, by which fire-retardant-treated wood shakes and shingles must be treated with chemicals.
ASTM D1970 NRCA Roofing Manual: Steep-slope Roof Systems (2025), Section 3.1—Underlayment Materials
Specification for self-adhering polymer-modified bituminous sheet used as steep-roofing underlayment for ice-dam protection, addressing thickness, tear resistance, adhesion, low-temperature flexibility and thermal stability.
ASTM D8257 NRCA Roofing Manual: Steep-slope Roof Systems (2025), Section 3.1—Underlayment Materials (Synthetic Sheets)
Specification for mechanically attached polymeric (synthetic) roof underlayments used in steep-slope roofing, approved December 2020 and referenced in the 2024 IBC and IRC.
ASTM D4869 NRCA Roofing Manual: Steep-slope Roof Systems (2025), Section 3.1—Underlayment Materials (Asphalt Felts, ASTM D4869)
Specification for asphalt-saturated organic felt shingle underlayment used in roofing, with four classifications (Types I–IV); Type IV (#26) equals ASTM D226 Type II (No. 30 felt) and Type II (#13) equals ASTM D226 Type I (No. 15 felt).
ASTM D3462 NRCA Roofing Manual: Steep-slope Roof Systems (2025), Section 4.1—Asphalt Shingle Standards
Specification for asphalt shingles made from glass felt and surfaced with mineral granules, addressing tear strength, fastener pull-through resistance and pliability; NRCA recommends specifying shingles complying with it.
ASTM D3018 NRCA Roofing Manual: Steep-slope Roof Systems (2025), Section 4.1—Asphalt Shingle Standards
Specification for Class A asphalt shingles surfaced with mineral granules, addressing fire test classification, wind resistance, and loss of volatile matter after heating.
UL 2218 impact resistance classes NRCA Roofing Manual: Steep-slope Roof Systems (2025), Section 4.1—Impact Resistance Rating
Impact Resistance of Prepared Roof Coverings, providing Classes 1 through 4, with Class 1 the least and Class 4 the greatest measured impact resistance.
ASTM C1167 tile grades NRCA Roofing Manual: Steep-slope Roof Systems (2025), Section 4.1—Clay and Concrete Tile Materials (Standards)
Clay roof tile grades based on frost resistance: Grade 1 resists severe frost action, Grade 2 moderate frost action, and Grade 3 has negligible frost resistance.
Impermeable synthetic sheet underlayment NRCA Roofing Manual: Steep-slope Roof Systems (2025), Section 3.1—Underlayment Materials (Synthetic Sheets)
An underlayment with a water vapor transmission rating of less than 0.1 perms, which NRCA recommends against over unvented or inadequately ventilated attics.
Equiviscous temperature (EVT) Roofing Construction and Estimating, Chapter 10 — Built-Up Roofing
The bitumen temperature at which 125 centipoise viscosity is attained—the optimum application temperature; roofing bitumen should be applied within 25°F of the EVT.
Surface Roughness B IBC 2021 Section 1609.4.2
Urban and suburban areas, wooded areas, or other terrain with numerous closely spaced obstructions the size of single-family dwellings or larger.
Nesting (asphalt shingle re-cover) NRCA Roofing Manual: Steep-slope Roof Systems (2025), Asphalt Shingle Roof Systems, Chapter 6—Reroofing, Section 6.5
Application of an additional layer of shingles over an existing layer where the top edge of the new shingles butts against the lower edge of the existing shingles; underlayment is not part of this re-cover system.
S-tile NRCA Roofing Manual: Steep-slope Roof Systems (2025), Section 4—Clay and Concrete Tile (S-tile)
A roof tile profile, also called one-piece pan and cover, laid in a single layer with a course-to-course overlap.
Solid sheathing requirement for wood shingles/shakes IBC 2021 Section 1507.8.1.1
Solid sheathing is required where the average daily January temperature is 25°F (−4°C) or less, or where ice may form along eaves causing a backup of water.
Wood structural panel roof sheathing exposure durability IBC 2021 Section 2304.8.2
Roof sheathing panels must be manufactured with exterior glue (Exposure 1 or Exterior) for moisture resistance.
Wood boards (roof decking) NRCA Roofing Manual: Steep-slope Roof Systems (2025), Section 2.2—Wood Planks and Wood Boards
Lumber less than 2 inches thick, typically 4 to 12 inches wide; boards thinner than nominal 1 inch are not considered strong enough to support roof loads.
Formulas to Know
Roof slope from rise and run, and its relation to pitch
Slope (in 12) = (Total Rise ÷ Total Run) × 12; Pitch = Total Rise ÷ Total Span; Slope = 2 × Pitch (e.g., 7'6" rise over 15' run = (7.5/15) × 12 = 6 in 12)Symmetric gable/truss geometry: run, rise, ridge elevation, rafter line, and angle
Run = Span ÷ 2; Rise = Run × (pitch/12); Ridge elevation = top-of-wall elevation + Rise; Rafter length = √(Run² + Rise²); Slope angle = arctan(Rise ÷ Run)Actual (sloped) roof area from plan area using slope-conversion factor
Sloped area = plan-view area × slope factor; factors: 2:12 = 1.014, 3:12 = 1.031, 4:12 = 1.054, 6:12 = 1.118 (= √(12²+6²)/12); take off each differently sloped section separatelyActual rafter length from horizontal run using slope factor
Rafter length = run (full depth of a single-plane porch) × slope factor (e.g., 10 ft × 1.031 = 10.3 ft; 12 ft × 1.054 = 12.6 ft)Ridge length of a conventionally framed hip roof
Ridge = L − [2 × (W/2)] = L − W (e.g., 40 ft − 20 ft = 20 lin ft; 60 ft − 36 ft = 24 ft)Hip rafter length (plan and true)
Plan length of hip = 1.414 × run (√2, for the 45° plan diagonal); True hip length = √(run² + run² + rise²) (e.g., √(18²+18²+9²) = 27.00 ft)Actual valley length where roofs of unequal slope intersect
Valley length = run of the low-sloping roof × valley length factor (e.g., 24 ft × 1.247 = 29.93 lin ft)Shingle bundles with waste
Bundles = (total sloped area ÷ 100 sq ft per square) × 3 bundles/square × 1.10 waste, rounded up (e.g., 25.33 sq × 3 × 1.10 = 83.6 → 84 bundles)Flashing piece counts (step and counterflashing)
Step pieces = wall length ÷ 2 ft per piece, rounded up (42 ÷ 2 = 21 → 22); Counterflashing = wall length ÷ 8 ft section, rounded up, then × 1.10 waste, rounded up (42 ÷ 8 = 5.25 → 6; 6 × 1.10 = 6.6 → 7)Roof live load reduction factors and drain sump sizing
R1 = 1.0 for At ≤ 200 sq ft; R1 = 1.2 − 0.001At for 200 < At < 600; R1 = 0.6 for At ≥ 600 sq ft. R2 = 1.0 for F ≤ 4; R2 = 1.2 − 0.05F for 4 < F < 12; R2 = 0.6 for F ≥ 12 (F = inches of rise per foot). Drain sump minimum = drain bowl diameter + 24 in. (12 in. bowl → 36 in. × 36 in.)