Exam Cheat Sheet · Quick Reference
Alabama Insulation 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
50
Passing score
70%
Exam time
120 min
Administered by
PSI Services Contractor
Format
Reference materials allowed
Alabama State Portion 50 questions
General Knowledge and Theory
8 Q · 16%
R-value and U-value concepts and their relationshipHeat transfer mechanisms: conduction, convection, and radiationTypes of insulation materials and their applicationsBuilding thermal envelope definition and componentsClimate zones and minimum insulation requirements by zoneVapor retarders and moisture controlBuilding codes and standards governing insulation (IRC, IECC, ASHRAE)Thermal comfort principles and factors affecting occupant comfort
Plan Reading, Materials, Estimating, and Take-Offs
5 Q · 10%
Reading and interpreting architectural plan views, elevations, and section drawingsIdentifying symbols, lines, dimensions, and notes on construction drawingsScales and scale drawings using architect's scaleQuantity takeoff and material estimating methodsPre-design, unit-cost, and complete cost estimate typesBuilding permits, inspections, and certificate of occupancy requirementsIRC building codes and climatic/geographic design criteria applicable to insulationInsulation R-value requirements by location (walls, ceilings, attics, floors, foundations) per energy codes
Spray-On Application
4 Q · 8%
Materials used in spray-on application (cellulose, fiberglass, rock wool, slag wool)Open-cell vs. closed-cell foam insulation types and propertiesR-values and thermal performance of spray-applied insulation materialsEquipment and application techniques for wet-spray insulationDrying time, moisture content requirements, and vapor retarder usePre-installation inspection, job site preparation, and application precautionsFire resistance ratings and thermal barrier requirements for spray-applied foamsHealth and safety precautions during spray-on insulation installation
Batt/Roll Insulation
4 Q · 8%
R-value ratings and thickness relationships for batt and roll productsFacing types and vapor retarder function (kraft paper, foil, unfaced)Stapling methods for faced insulation (inset, face stapling, pressure fit)Installation by location (sidewalls, attics, floors, crawl spaces, basements)Handling obstructions within cavities (wiring, plumbing, junction boxes)High-density and cathedral ceiling batt applicationsHealth and safety precautions when handling fiberglass and mineral woolMaterial types for batt and roll insulation (fiberglass, rock wool, slag wool, cotton)
Blown or Loose-Fill Insulation (Includes Dense-Packing)
4 Q · 8%
Types of loose-fill insulation materials (cellulose, fiberglass, mineral wool, perlite, vermiculite)Dense-pack installation density requirements and settling preventionR-value characteristics and coverage chart requirements by material typeAttic and sidewall application procedures and equipment operationPre-installation inspection and preparation requirementsClearance requirements around heat-producing devices, chimneys, and recessed lightsMoisture resistance, fluffing, voids, and convective heat loss concernsHealth and safety requirements for installer protection (PPE, respiratory protection)
Rigid-Board and Reflective Insulation
2 Q · 4%
Types of rigid board insulation materials (EPS, XPS, polyisocyanurate, perlite, mineral fiber, cellular glass, wood fiberboard)R-values and thermal drift of rigid board insulation productsFire safety requirements and thermal barrier coverings for foam insulationMoisture resistance, vapor permeance, and below-grade applications of rigid board insulationExterior Insulation and Finish Systems (EIFS) components, barrier-type vs. drainable-type systemsRadiant heat transfer principles: emittance, reflectance, and emissivityRadiant barrier installation locations, airspace requirements, and safety considerationsReflective insulation products, R-value directionality, and applicable ASTM standards
Ventilation
5 Q · 10%
Attic and rafter space ventilation requirements (IRC Section R806)Minimum net free ventilating area ratios (1/150 and 1/300 rules)Unvented attic and enclosed rafter assembly conditionsEave, soffit, and ridge vent placement and airflow clearanceWhole-house mechanical ventilation system design and airflow ratesLocal exhaust rates for kitchens and bathroomsVapor retarder interaction with attic ventilation requirementsExhaust duct termination and outdoor discharge requirements
Vapor Barrier and Retarders
4 Q · 8%
Vapor retarder classification by perm rating (Class I, II, and III materials)Proper placement of vapor retarders by climate zone (warm-side vs. cold-side installation)Condensation and dew point principles affecting moisture control in wall assembliesMoisture migration mechanisms in building envelopes (bulk moisture, capillary action, air leakage, vapor diffusion)Crawl space vapor retarder requirements and installation (soil cover, lap and seal requirements)Air retarders and housewraps (distinction from vapor retarders, installation requirements)Vapor retarder installation methods (polyethylene sheeting, kraft-faced batts, vapor barrier paints)Attic ventilation requirements in relation to vapor retarder use
Safety and Employee Protection
8 Q · 16%
Fall protection systems: guardrail, safety net, and personal fall arrest requirementsScaffold safety: erection, capacity, access, and fall protectionLadder safety: types, load ratings, and safe use requirementsPersonal protective equipment selection, provision, and maintenanceFire protection and prevention: extinguishers, flammable liquid storage, and fire prevention plansHazardous and toxic substance exposure limits and controls (asbestos, air contaminants)Confined space entry procedures and permit requirementsTool safety: hand tools, power tools, and machine guarding
Other Insulation Applications
6 Q · 12%
Structural insulated panels (SIPs): composition, R-values, and installationInsulating concrete formwork (ICF): EPS forms, concrete placement, and thermal performanceStraw bale construction: types, R-values, moisture concerns, and fire resistanceEarth-based insulation systems: thermal mass, earth sheltering, and rammed earthHistorical insulation products: asbestos identification, health hazards, and removal proceduresUrea formaldehyde foam insulation (UFFI): history, health concerns, and identificationCeramic and reflective insulating coatings: product description, application, and limitationsEmerging insulation technologies: aerogels, vacuum insulation panels, gas-filled panels, and phase-change materials
Key Distinctions
Carbon monoxide alarmvsCarbon monoxide detector
An alarm is a single- or multiple-station unit combining sensor, control components and the alarm notification appliance in one device, while a detector has an integral sensor that transmits an alarm signal to a connected alarm control unit and contains no notification appliance.
IRC 2021 Section R202 Definitions (Carbon Monoxide Alarm and Carbon Monoxide Detector); IRC 2018 Section R202Open-cell SPFvsClosed-cell SPF
Open-cell semirigid water-blown polyurethane foam is R-3.81 per inch and expands up to 120 times its liquid volume, while closed-cell SPF is R-6 to R-7 per inch and expands at an average ratio of about 30:1 because its cells hold blowing agent rather than air.
Insulation Handbook (2001), Chapter 10 - Foamed-in-Place Insulation, Open-cell SPF sectionEPS (expanded polystyrene)vsXPS (extruded polystyrene)
EPS R-value varies with density, whereas XPS holds a consistent R-value of 5.0 per inch regardless of density and has greater compressive strength, making it suitable below grade on foundation walls.
Insulation Handbook (2001), Chapter 11 - Rigid Board InsulationCellulose loose-fillvsFiberglass and rock wool loose-fill
Cellulose absorbs 5 to 20 percent of its weight in moisture (a listed disadvantage), while fiberglass and rock wool absorb less than 1 percent of their weight.
Insulation Handbook (2001), Chapter 7 - Loose-Fill Insulation, Cellulose sectionSlag woolvsRock wool
Within the U.S. mineral wool industry, slag wool accounts for roughly 80 percent of production versus about 20 percent for rock wool.
Insulation Handbook (2001), Chapter 7 - Loose-Fill Insulation, Mineral Wool sectionAir leakagevsVapor diffusion
More than 90 percent of moisture entering a perimeter structural cavity comes from air leakage (air draining as a fluid through imperfections toward low pressure), with 10 percent or less from vapor diffusion.
Insulation Handbook (2001), Chapter 4 - Vapor and Air RetardersWhole-wall R-valuevsClear-wall or center-of-cavity R-value
Whole-wall R-value includes interface details (wall-wall corners, wall-roof, wall-floor, wall-door, wall-window) in addition to the clear-wall area, making it a better criterion for comparing wall systems.
Insulation Handbook (2001), Chapter 3 - Insulation Fundamentals and PrinciplesPerlite loose-fillvsBlown loose-fill insulation
Perlite is bagged and must be poured into place — commonly into concrete block cavities in masonry construction — and is not suitable for blow-in installation methods.
Insulation Handbook (2001), Chapter 7 - Loose-Fill InsulationLow-density fiberglass battsvsHigh-density fiberglass batts
Low-density batts are rated R-11 for 2×4 walls and R-19 for 2×6 walls, while high-density batts are R-15 for 2×4 walls; high-density R-30C 'superbatts' for cathedral ceilings are 8¼ to 8½ in. thick versus 9½ to 10 in. for standard R-30, so they fit nominal 2×10 framing while keeping a 1-inch vent airspace.
Carpentry and Building Construction, Section 31.1 — Fiberglass Insulation R-ValueFirst number on a panel stamp (e.g., 32 in 32/16)vsSecond number on a panel stamp (e.g., 16 in 32/16)
The number before the slash is the maximum support spacing in inches for roof sheathing use; the number after the slash is the maximum support spacing for subflooring use.
Carpentry and Building Construction, Section 19.5, Pages 562-563Collar ties supporting a ceilingvsCollar ties used only structurally
Ties that support a ceiling are required at every rafter pair, while purely structural ties go at every fourth rafter pair at 16" OC spacing and every third rafter pair at 24" OC.
Carpentry and Building Construction, Section 19.3, Page 542Roof-opening headers kept in the plane of the roof framingvsPlumb roof-opening headers
In-plane headers are easier to install and are sometimes used for skylights, while plumb headers accommodate vertical objects passing through the framing such as chimneys.
Carpentry and Building Construction, Section 19.3, Page 547-548Class A fire extinguishervsClass B fire extinguisher
Class A covers wood, paper, cloth and plastic, while Class B (or combination A:B, A:B:C) covers grease, oil and chemicals; Class C is electrical equipment and Class D is combustible metals.
Carpentry and Building Construction, Construction Safety & Health, Page 81Attic ventilation at 1/150vsAttic ventilation at 1/300 exception
IRC R806.2 requires minimum net free ventilating area of 1/150 of the vented space area, with an exception permitting 1/300 when specific vapor-retarder and ventilator-placement conditions are met.
IRC 2021 Section R806.2Key Terms
Carbon monoxide alarm IRC 2021 Section R202 Definitions (Carbon Monoxide Alarm and Carbon Monoxide Detector); IRC 2018 Section R202
Per IRC R202, a single- or multiple-station alarm that incorporates a sensor, control components and an alarm notification appliance in one unit.
Ceiling height IRC 2021 Section R202 Definitions (Ceiling Height); IRC 2018 Section R202
Per IRC R202, the clear vertical distance from the finished floor to the finished ceiling, measured to finished surfaces rather than structural framing.
Emergency escape and rescue opening IRC 2021 Section R202 Definitions (Emergency Escape and Rescue Opening); IRC 2018 Section R202
Per IRC R202, an operable exterior window, door or similar device that provides a means of escape and access for rescue in the event of an emergency.
Shear wall Carpentry and Building Construction, Page 378
A wall designed to resist lateral (sideways) forces, commonly required in earthquake-prone areas; specific sheathing nail spacing creates it, shear strength at house corners is crucial, and it must be fastened to the framing above and to the sill plate and foundation below.
Consolidation Carpentry and Building Construction, Page 233
The process that removes air pockets and forces concrete into all parts of the forms for a dense, uniform placement.
Stringer Carpentry and Building Construction, Page 747
The long piece of 2× lumber that supports the stair treads and risers.
Sound Transmission Class (STC) Carpentry and Building Construction, Section 31.2 — How Sound Travels
A numerical rating of a material's or assembly's ability to reduce airborne sound transmission; the higher the STC number, the better the sound barrier.
Flanking path Carpentry and Building Construction, Section 31.2 — Flanking Paths
A sound bypass such as a small opening in an acoustical assembly; a hole as small as 1 square inch in an STC 50 wall can reduce that wall's performance to about STC 30.
Whole-wall R-value (Rww) Insulation Handbook (2001), Chapter 3 - Insulation Fundamentals and Principles
An R-value estimation for the whole opaque wall that includes both the clear-wall area and typical interface details (wall-wall corners, wall-roof, wall-floor, wall-door, wall-window).
Knee wall Carpentry and Building Construction, Section 31.1 — Where to Insulate (Walls)
A half-height wall often found in attics; in a one-and-a-half-story house, second-floor knee walls separate heated from unheated space and must be insulated just as if they were exterior walls.
Closed cornice Carpentry and Building Construction, Section 19.4, Page 552
A cornice on a house with no rafter overhang; seldom used on newer houses because the lack of overhang makes it difficult to provide attic ventilation (no soffit-vent location).
Room-finish schedule Carpentry and Building Construction, Section 2.3, Page 57
A plan schedule identifying the materials and finishes to be used for floors, walls and ceilings in each room and hallway (for example, strip-oak flooring, pine trim, painted drywall, wood paneling).
Rafter span IRC Section R802.4.1; IRC 2018 Section R802.4.1
Per IRC R802.4.1, the span measured along the horizontal projection of the rafter — not along the actual rafter length — which governs how rafter span tables are read.
Purlin brace IRC 2021 Section R802.4.5; IRC 2018 Section R802.4.5
Per IRC R802.4.5, a 2×4 brace installed to a bearing wall at a slope not less than 45 degrees from horizontal and spaced not more than 4 feet on center; braces should be no longer than 8 feet and must not connect to non-bearing walls.
IECC tradeoff worksheet approach Insulation Handbook (2001), Chapter 6 - Building Codes, Standards, and Regulations
A compliance method in which increasing total glazing area requires improving window thermal performance (lower U-value) or increasing insulation in the opaque portion (higher R-value) to satisfy the overall U-value requirement.
Radiant-heat barrier (draped installation) Carpentry and Building Construction, Section 31.1 — Radiant-Heat Barriers
A barrier draped loosely over rafters before roof sheathing is applied so it droops to leave at least 1 inch of air space beneath the sheathing, improving effectiveness and creating an air channel for soffit and ridge vent airflow.
Formulas to Know
U-value from R-value of an assembly
U = 1 / R; e.g., R-20 wall → U = 1/20 = 0.05 (lower U = better insulating value)Excavation volume in cubic yards
(house length + clearance both sides) × (house width + clearance both sides) × depth ÷ 27; e.g., 44' × 30' × 7' = 9,240 cu ft ÷ 27 ≈ 342 cu ydBoard feet of rafter framing from board-feet table
(roof surface area ÷ 100) × table board feet per 100 sq ft; e.g., 2,100 ÷ 100 = 21, 21 × 102 (2×6 @ 16" OC) = 2,142 bd ft (includes common, hip/valley rafters, ridge boards, collar ties)Board feet of ceiling plank from estimation table
2×6 plank at 16" OC = 88 bd ft per 100 sq ft (2×6 @ 24" OC = 63; 2×4 @ 16" OC = 42; 2×8 @ 16" OC = 117)Roof sheathing panel count with waste allowance
Roof area ÷ 32 sq ft per panel, then add 5% for trim and waste; e.g., 72.19 × 0.05 = 3.6, 72.19 + 3.6 = 75.79 → 76 sheetsCrawl-space ventilation net area
1 sq ft of net venting per 150 sq ft of crawl-space area; e.g., 1,200 ÷ 150 = 8 sq ftAttic/rafter-space net free ventilating area
1/150 of the area of the vented space (1/300 permitted when the vapor-retarder and ventilator-placement conditions are met)Equal side setback from a site plan
(lot depth − house depth) ÷ 2; e.g., (78 − 42) ÷ 2 = 18'-0"Diagonal distance from a house corner to the lot corner
Diagonal = √(front setback² + side setback²); e.g., √(24² + 18²) = √900 = 30'-0" (3-4-5 triangle × 6)Rear yard depth from a site plan
Rear yard = lot width − front setback − house width; e.g., 110 − 24 − 30 = 56'-0"Average and maximum-difference lot elevation
Average = sum of four corner elevations ÷ 4 (e.g., (4.00+3.00+2.00+3.00) ÷ 4 = +3.00'); maximum difference = highest corner − lowest corner (4.00 − 2.00 = 2.00')Deck-and-pool overall footprint
(pool length + 2 × deck width) × (pool width + 2 × deck width); e.g., (32+6+6) × (16+6+6) = 44' × 28' = 1,232 sq ftRafter span adjustment for raised ceiling joists/rafter ties
Multiply tabulated rafter span by the Hc/Hr adjustment factor; Hc/Hr = 1/3 → factor 0.67 (Hc and Hr measured vertically above the top of the rafter support walls)Construction fire extinguisher coverage
One extinguisher rated not less than 2A per 3,000 sq ft of protected building area, or major fraction thereof