Exam Cheat Sheet · Quick Reference
Louisiana Roofing, Sheet Metal and Siding
Louisiana · 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
50
Passing score
70%
Exam time
120 min
Administered by
PSI Services Contractor
Format
Reference materials allowed
Louisiana State Portion 50 questions
Estimating and Plan Reading
5 Q · 10%
Measuring and calculating roof area (level and sloped roofs)Roof slope and pitch calculations using slope factorsQuantity takeoff for specific roofing materials (shingles, tile, slate, metal panels, roll roofing)Estimating underlayment quantities including lap and overcut allowancesLabor unit pricing and production rate calculationsAdjusting published labor costs to actual crew wagesEstimating gutter, downspout, and accessory quantitiesWaste factors for roofing materials
Surface Preparation and Planning
5 Q · 10%
Roof deck inspection procedures and acceptance criteriaRoof deck types and material requirements by roofing systemPlywood and OSB sheathing specifications, thickness, and grading standardsDeck surface condition requirements before roof system applicationRoof slope and drainage design requirementsUnderlayment selection and installation based on roof slope and material typeEvaluation of existing roof systems for re-cover versus replacementStructural load considerations for roof decks including dead and live loads
Steep and Low Slope Roofing including BUR and Waterproofing
18 Q · 36%
Asphalt shingle types, materials, and installation requirementsSteep slope roof underlayment types, configurations, and applicationBuilt-up roofing (BUR) components, bitumens, and installation methodsLow-slope membrane roof systems including polymer-modified bitumen, EPDM, and thermoplastic membranesClay, concrete, and slate tile roof systems including profiles, materials, and installationWood shake and wood shingle roof systems including grades, materials, and installationRigid board insulation types, R-values, and thermal performance for low-slope roofsFlashing, drainage, fire classification, and wind uplift requirements per IBC/IRC
Roofing Components
10 Q · 20%
Asphalt shingle types, materials, and UL fire/wind ratingsRoof deck types and sheathing requirements for steep-slope systemsUnderlayment types, configurations, and slope requirementsValley flashing and drip edge componentsWood shingles and shakes: grades, types, and installation requirementsClay, concrete, and slate tile types, profiles, and physical propertiesMetal roofing and siding materials, seam types, and panel systemsBuilt-up and elastomeric roofing membrane components and substrate requirements
Safety
5 Q · 10%
Fall protection requirements for roofing work (low-slope and steep roofs)Personal fall arrest systems: components, specifications, and proper useGuardrail systems: height, strength, and construction requirementsScaffold safety: capacity, platform construction, and fall protectionLadder and stairway safety requirementsFire protection and prevention on construction sitesPersonal protective equipment selection, use, and employer responsibilitiesAsbestos hazards in roofing and construction: identification, exposure limits, and work practices
Repairs and Reroofing
7 Q · 14%
Reroofing terminology: re-covering vs. tear-off and replacement definitionsEvaluation of existing roof systems prior to reroofing (interior inspection, deck underside, perimeter, rooftop inspection)Roof deck condition assessment and moisture detection methods (core cuts, infrared thermography, nondestructive testing)Re-covering eligibility criteria by roof system type (asphalt shingle, metal shingle, slate, clay/concrete tile, wood shake/shingle, membrane)Flashing inspection and treatment during reroofing (base flashings, counterflashings, drip edge, penetration flashings)Building code requirements for reroofing under IBC and IRC (Section 1512 re-cover and replacement provisions, layer limits, fire classification)Repair techniques by roof covering type (asphalt shingle patching, wood shingle/shake replacement, slate nail-and-bib method, membrane repairs, tile repair)Identifying and locating roof leaks (attic inspection, water staining patterns, chimney/valley/vent flashing failures, miscellaneous leak sources)
Key Distinctions
Positive Method (roof measurement)vsNegative Method (roof measurement)
The positive method divides an irregular roof into rectangles and adds their areas, while the negative method extends roof lines to form one large rectangle and subtracts non-roof areas; both yield identical results.
Roofing Construction and Estimating, Chapter 1, Pages 7-8Fiberglass Asphalt ShinglesvsOrganic Asphalt Shingles
Fiberglass shingles use a fiberglass base mat saturated with asphalt, while organic shingles use a cellulose-fiber base mat.
Roofing Construction and Estimating, Chapter 4—Asphalt ShinglesBattens on tile roofs (optional)vsBattens on tile roofs (required)
Battens are optional on slopes of 2-1/2 in 12 up to steeper pitches, but become required at slopes of 7 in 12 and steeper.
Tile Roofing, Chapter 7Shielded/Lead-Covered Conductors (bend radius)vsNonshielded Conductors (bend radius)
Shielded or lead-covered conductors over 1000 volts must not be bent to a radius less than 12 times the overall diameter, while nonshielded conductors require a minimum of 8 times the overall diameter.
NEC 305.5Type MV-90 CablevsType MV-105 Cable
MV-90 has a maximum operating temperature of 90°C, while MV-105 has a maximum operating temperature of 105°C; both are suitable for dry or wet locations.
NEC Table 315.10(A)Direct-Buried Cables over 1000V–22kV (cover depth)vsCables over 22kV–40kV in rigid metal conduit (cover depth)
Direct-buried cables over 1000V AC through 22kV require 750 mm (30 in.) minimum cover under general conditions, while cables over 22kV through 40kV in rigid metal conduit require only 150 mm (6 in.).
NEC Table 305.15(A)Conductors rated over 1000V AC in same enclosure as ≤1000V conductorsvsConductors all rated ≤1000V AC in same enclosure
Conductors over 1000V AC shall NOT occupy the same enclosure, cable, or raceway as conductors rated 1000V or less unless specific NEC exceptions apply, whereas conductors all at 1000V or below may share enclosures without that restriction.
NEC 305.4Nail penetration into plywood deck (<¾ inch thick)vsNail penetration into wood plank/board deck
For plywood decks less than ¾ inch thick, nails must extend at least ⅛ inch through the underside, while for wood plank or board decks nails must penetrate at least ¾ of an inch into the deck.
NRCA Roofing Manual: Steep Slope Roof Systems, Section 4.2—Asphalt Shingle Roof System Design and Installation (Fasteners)Vertical drain stack offset ≤45 degrees from verticalvsVertical drain stack offset >45 degrees from vertical (above lowest branch)
An offset of 45 degrees or less from vertical is sized as a straight vertical drain, while an offset of more than 45 degrees above the lowest horizontal branch must be sized as a building drain based on accumulated fixture units.
International Residential Code, Page 671 (Section P3006.2)CPVC pipe ≤1 inch diameter (horizontal support spacing)vsPVC pipe (horizontal support spacing)
CPVC pipe or tubing 1 inch and smaller requires horizontal supports at maximum 3-foot intervals, while PVC pipe requires horizontal supports at maximum 4-foot intervals.
International Residential Code, Page 621; International Plumbing Code, Page 3-4Streamlined soldered / recessed threaded fittings (equivalent length)vsStandard threaded fittings (equivalent length)
Equivalent length allowances shown in the pipe sizing tables apply to streamlined soldered and recessed threaded fittings; for standard threaded fittings, those allowances must be doubled.
International Residential Code, Page 911; International Plumbing Code, Page E-12Emergency Action Plan for ≤10 employeesvsEmergency Action Plan for >10 employees
For employers with 10 or fewer employees the plan may be communicated orally and need not be maintained in writing, while larger employers must maintain a written plan.
OSHA 1926 CFR 29, §1926.35(e)(3)Key Terms
Competent Person (OSHA) OSHA 1926 CFR 29, Page 31
Per OSHA 29 CFR 1926.32(f), one capable of identifying existing and predictable hazards who has authorization to take prompt corrective measures to eliminate them.
Fire Extinguisher Rating Requirement (OSHA) OSHA 1926.150(c)(1)(i)
Per OSHA 1926.150(c)(1)(i), a fire extinguisher rated not less than 2A must be provided for each 3,000 square feet of protected building area.
First Aid Kit Inspection Frequency (OSHA) OSHA 1926 CFR 29, Page 33
Per OSHA 1926.50, the contents of a first aid kit shall be checked before each job and at least weekly on each job to ensure expended items are replaced.
Qualified Equipment Operator (OSHA) OSHA 1926 CFR 29, Page 29
Per OSHA 1926.20(b)(4), only employees qualified by training or experience shall be permitted to operate equipment and machinery.
Danger Sign Specifications (OSHA) OSHA 1926 CFR 29, Page 201
Per OSHA 1926.200(b)(2), danger signs shall have red as the predominating color for the upper panel, black outline on borders, and a white lower panel for additional wording.
High Voltage Danger Sign (NEC) NEC 305.12
Per NEC 305.12, danger signs conspicuously posted at all access points to conductors in raceway and cable systems over 1000 volts must state: DANGER—HIGH VOLTAGE—KEEP OUT.
Qualified Person for Type MV Cable (NEC) NEC 315.30
Per NEC 315.30, installation and testing of Type MV cable must be performed by a qualified person with documented training and experience, and cable joints require qualified persons with documented MV joint training.
High-Voltage Conductor Termination in Buildings (NEC) NEC 235.412
Per NEC 235.412, where voltage exceeds 35,000 volts between conductors entering a building, they must terminate in a switchgear compartment or vault; they may not terminate at just any accessible location.
Raceways and Non-Electrical Pipes (NEC) NEC 300.8
Per NEC 300.8, raceways or cable trays containing electrical conductors shall not contain any pipe, tube, or equal for steam, water, air, gas, drainage, or any service other than electrical.
Drainage Fixture Unit (d.f.u.) International Residential Code, Page 667-668 (Section P3004.1, Table P3004.1)
A numerical factor assigned to plumbing fixtures representing the probable hydraulic discharge load used to compute and size DWV system piping per IRC P3004.1.
Branch Interval International Residential Code, Page 13 (Section R202, Definitions)
Per IRC Section R202, a vertical measurement of 8 feet or more in developed length between connections of horizontal branches to a drainage stack, measured downward from the highest horizontal branch.
Sweep (drainage fitting) International Residential Code, Page 25 (Section R202, Definitions)
Per IRC Section R202, a drainage fitting designed to change pipe direction with a longer turning radius than a bend, resulting in a less turbulent flow pattern.
Steel Shield Plate (pipe protection) IRC P2603.2.1
Per IRC P2603.2.1, when piping passes through structural members within 1½ inches of the nearest edge, a steel shield plate of minimum 0.0575 inch (No. 16 gauge) thickness is required.
Pipe Sleeve Through Foundation Wall International Residential Code, Page 620; International Plumbing Code, Page 3-2
Per IRC P2603.4 and IPC 305.3, a sleeve built into a foundation wall for a pipe passage must be two pipe sizes greater than the pipe passing through the wall.
Minimum Conductor Size for 8001–15,000V MV Cable NEC Table 315.12(A)
Per NEC Table 315.12(A), the minimum conductor size for Type MV cable rated 8001–15,000 volts is 2 AWG for copper, aluminum, or copper-clad aluminum.
Elevation Pressure Loss (water supply) IRC Appendix P, Section AP103.2.2
Per IRC Appendix P (AP103.2.2), static pressure loss due to elevation rise in a water supply system is calculated at 0.433 psi per foot of elevation change.
Formulas to Know
Roof Area — Positive Method
Total Roof Area = Sum of areas of all individual rectanglesRoof Area — Negative Method
Total Roof Area = Area of large enclosing rectangle - Sum of non-roof areasWater Supply Elevation Pressure Loss
Pressure Loss (psi) = 0.433 × Elevation Rise (ft)Fitting Equivalent Length (standard threaded fittings)
Equivalent Length (threaded) = 2 × Tabulated Equivalent Length (soldered/recessed)Total Pipe Friction Length
Total Friction Length = Actual Pipe Length + Sum of Equivalent Lengths for all fittings and valvesDWV Load Calculation
Total DWV Load = Sum of drainage fixture unit (d.f.u.) values for all connected fixtures