Tennessee - NASCLA Commercial Building Contractor Examination

Key Concepts

OSHA recordkeeping (NASCLA Ch. 11, OSHA Recordkeeping, p.104) - Form 300A, the annual summary of work-related injuries and illnesses, must be conspicuously posted by February 1 and kept in place until at least April 30 of the year following the year covered. - Forms 300, 300A and 301 must be retained five years following the year to which they pertain. - Employers with 10 or fewer employees are exempt from maintaining Forms 300, 300A and 301 — unless they receive an annual survey form from the Bureau of Labor Statistics (BLS) or OSHA (Who Needs to Complete the Forms). - Form 301 is the individual incident report; an insurance or workers' compensation form providing the same details…

Key Concepts

Lateral soil loads and presumptive values (IBC Ch. 16 & 18) - Foundation walls with horizontal movement restricted at the top are designed for at-rest pressure; retaining walls free to move and rotate at the top may use active pressure (Sec. 1610.1). Exception: walls extending not more than 8 feet below grade and laterally supported at top by flexible diaphragms may use active pressure. - Table 1806.2 presumptive values (vertical / lateral / friction): Class 1 crystalline bedrock 12,000 psf, 1,200 psf/ft, 0.70; Class 2 sedimentary and foliated rock 4,000 / 400 / 0.35; Class 3 sandy gravel and gravel (GW, GP) 3,000 / 200 / 0.35; Class 4 sand, silty sand, clayey sand, silty gravel, clayey…

Key Concepts

Mix proportions. A typical concrete mix is 10% to 15% portland cement, 60% to 75% fine and/or coarse aggregate, and 15% to 20% water. Entrained air, when used, typically ranges from 5% to 8% of the volume; admixtures when used are roughly 2% to 5% (Module 23212, Section 3.1.0).

Water-cementitious material (w/c) ratio. Most concrete is made with a w/c ratio between 0.35 and 0.70 — the water represents 35% to 70% of the weight of the cement (Section 3.1.0). Water weighs 8.33 lb/gal; a general rule suggests 5 to 6 gallons of water per 94-pound bag of cement (Section 1.2.5).

Key Concepts

Materials and standards (IBC 2021, Section 2103) - Concrete, clay/shale, stone, glass unit and AAC masonry units shall comply with Article 2.3 of TMS 602. Architectural cast stone conforms to ASTM C1364 and TMS 504; adhered manufactured stone veneer units to ASTM C1670. (Sec. 2103.1) - Exception: structural clay tile used nonstructurally for fireproofing of structural members and wall furring is not required to meet the compressive strength specifications; its fire-resistance rating shall be determined per ASTM E119 or UL 263 and comply with Table 705.5. (Sec. 2103.1 Exception) - Mortar for masonry construction conforms to Articles 2.1 and 2.6 A of TMS 602 (Sec. 2103.2.1). Grout conforms to Article 2.2 of TMS 602 (Sec. 2103.3). **Metal…

Key Concepts

Scope and identification (IBC 2021) - The steel chapter governs the quality, design, fabrication and erection of steel construction (Section 2201.1). - Identification: structural steel elements per AISC 360; cold-formed steel members per AISI S100; cold-formed steel light-frame construction shall also comply with AISI S240 or AISI S220, as applicable (Section 2202.1).

Connections (IBC 2021) - Welding — see special inspection in Section 1705.2 (Section 2204.1); installation of high-strength bolts — see Section 1705.2 (Section 2204.2). - Anchor rods shall be set per the approved construction documents; threaded-end protrusion through the connected material shall fully engage the threads of the nuts but shall not be greater than the length of the threads on the bolts (Section 2204.3).…

Key Concepts

Lumber grading and identification - Sawn lumber used for load-supporting purposes must be identified by the grade mark of an approved lumber grading or inspection agency (IBC 2021, Section 2303.1.1). - In lieu of a grade mark, a certificate of inspection as to species and grade is permitted for precut, remanufactured or rough-sawn lumber and for sizes larger than 3 inches nominal thickness (Section 2303.1.1.1). - Required member sizes are computed on net (actual) dimensions, not nominal (Section 2304.2).

Fire-retardant-treated (FRT) and preservative-treated wood - FRT wood has a listed flame spread index of 25 or less; the ASTM E84/UL 723 test continues 20 minutes and the flame front shall not progress more than 10½ feet beyond…

Key Concepts

Vapor retarder classes (IBC 2021, Table 1404.3(1)). Class I = perm rating 0.1 or less; Class II = greater than 0.1 and not more than 1.0; Class III = greater than 1.0 and not more than 10. A tested 0.8 perm material is Class II.

Vapor retarder placement (Section 1404.3, Table 1404.3(2)). In Climate Zones 1 and 2, Class I and Class II vapor retarders are not permitted on the interior side of frame walls; only Class III is permitted.

Class II retarder + exterior foam sheathing (Section 1404.3.1, Table 1404.3.1). Where a Class II vapor retarder is used with foam plastic insulating sheathing as continuous insulation on the exterior, the continuous insulation must meet Table 1404.3.1…

Key Concepts

Safety glazing (hazardous locations, IBC 2021 Chapter 24) - Glazing in all fixed and operable panels of swinging, sliding and bifold doors is a hazardous location; one exception is glazed openings of a size through which a 3-inch-diameter sphere is unable to pass (Section 2406.4.1). - Glazing in an individual fixed or operable panel adjacent to a door is a hazardous location where the nearest vertical edge is within a 24-inch (610 mm) arc of either vertical edge of the door in a closed position and the bottom exposed edge is less than 60 inches above the walking surface (Section 2406.4.2). - Glazing in a window is hazardous only when all four conditions are met; one of…

Key Concepts

Gypsum board materials and limitations (IBC Ch. 25) - Gypsum wallboard or gypsum plaster shall not be used on any exterior surface exposed directly to the weather, and gypsum wallboard shall not be used where there is direct exposure to water or continuous high humidity (IBC 2021, 2508.2). - Water-resistant gypsum backing board shall not be used (1) over a vapor retarder in shower or bathtub compartments, or (2) where there will be direct exposure to water or in areas subject to continuous high humidity (2509.3). It shall be used as a base for tile in water closet compartment walls when installed per GA 216 or ASTM C840 (2509.2). - Installation standards for gypsum board and gypsum…

Key Concepts

Mechanical scope (Chapter 28). Section 2801.1: this chapter, the International Mechanical Code and the International Fuel Gas Code govern design, construction, erection and installation of mechanical appliances, equipment and systems. Masonry chimneys, fireplaces and barbecues shall comply with the International Mechanical Code and Chapter 21. The IFC, IPMC, IMC and IFGC govern use and maintenance; the International Existing Building Code, IMC and IFGC govern alteration, repair, relocation, replacement and addition.

Fixture calculations (2902.1.1). Divide total occupant load in half to get the occupant load of each sex, then apply Table 2902.1 ratios. Fractional numbers are rounded up to the next whole number; for multiple occupancies, fractions for each occupancy are first summed, then rounded up. - *Exception…

Key Concepts

Emergency and standby power (IBC 2021, Chapter 27)

• Load transfer: Emergency power systems shall automatically provide secondary power within 10 seconds after primary power is lost; standby power systems within 60 seconds, unless specified otherwise in the code (IBC 2702.1.4).
• Load duration: Emergency and standby systems shall provide the required power for a minimum duration of 2 hours without being refueled or recharged, unless specified otherwise (IBC 2702.1.5).
• Stationary generators required by the code shall be listed in accordance with UL 2200 (IBC 2702.1.1). Installation follows the IFC, NFPA 70, NFPA 110 and NFPA 111 (IBC 2702.1.3).
• Fuel-line protection, high-rise: Fuel lines supplying a generator set inside a high-rise shall be separated from…

Key Concepts

Bonds — what each guarantees (Ch. 3, Managing Risk — Types of Bonds) - Bid bond: guarantees the contractor, if awarded the job, will do the work at the submitted bid price, enter into a contract with the owner, and furnish the required performance and payment bonds; if the contractor defaults on the bid agreement, the bid bond can be used to make up the pricing difference with the next lowest bidder. - Performance bond: guarantees the contractor will complete a contract within its time frame and conditions. - Payment bond: guarantees subcontractors and suppliers they will be paid for work performed properly under the contract. - Maintenance bond: guarantees that for a stated period, *typically one…