Tennessee BC Combined Residential/Commercial/Industrial Contractor

Key Concepts

Reading civil drawings - Dimensions may be shown in engineering scale (feet and tenths of a foot) or architectural scale (feet, inches, and fractions of an inch). Plans used in excavation and grading work are likely to use engineering scale. (Module 22209, Section 1.0.0, Page 98) - A profile is the side view of a proposed project taken parallel to the center line, depicting heights, depths, and slopes. A cross section is a cutaway view perpendicular to the longitudinal axis or center line. (Module 22201, Trade Terms, Pages 361 and 401) - Highway packages may include cross-section sheets showing natural ground and the shape of finish grade every 50 feet or other established distance. *(Module 22209, Section…

Key Concepts

Scope and authority - The IRC applies to detached one- and two-family dwellings and townhouses not more than three stories above grade plane with a separate means of egress, and their accessory structures not more than three stories above grade plane (IRC Section R101.2). - The building official may render interpretations (R104.1), grant modifications for practical difficulties (R104.10) and approve alternative materials and methods (R104.11), but interpretations, policies and procedures shall not have the effect of waiving requirements specifically provided for in the code (R104.1). The board of appeals likewise shall not have authority to waive requirements of the code (R112.2); its members must be qualified by experience and training and not employees of the jurisdiction (R112.3),…

Key Concepts

Excavation safety / OSHA Subpart P - Type A cohesive soil requires an unconfined compressive strength of 1.5 tsf (144 kPa) or greater; Type B is greater than 0.5 tsf but less than 1.5 tsf; Type C is 0.5 tsf or less. Even at 1.5 tsf, soil is not Type A if it is fissured, subject to vibration, or previously disturbed (29 CFR 1926 Subpart P, App. A, para. (b)). - Ventilation or other adequate precautions must keep employees from exposure to flammable gas exceeding 20 percent of the lower flammable limit (1926.651(g)(1)(iii)). Related provisions require atmospheric testing before entry into excavations greater than 4 feet deep where oxygen deficiency (below 19.5 percent) or other hazardous atmospheres…

Key Concepts

Soil classification and presumptive load-bearing values (IBC Table 1806.2) - Class 3 — sandy gravel and gravel (GW, GP): vertical foundation pressure 3,000 psf; lateral bearing 200 psf/ft below natural grade; coefficient of friction 0.35. - Class 4 — sand, silty sand, clayey sand, silty gravel and clayey gravel (SW, SP, SM, SC, GM, GC): lateral bearing 150 psf/ft below natural grade; vertical 2,000 psf; friction 0.25. - Class 1 crystalline bedrock: 12,000 psf vertical, 1,200 psf/ft lateral, 0.70 friction. Class 2 sedimentary and foliated rock: 4,000 psf, 400 psf/ft, 0.35. - Lateral bearing pressures may be increased by the tabular value for each additional foot of depth, **to a value not greater than 15 times the…

Key Concepts

Slabs, footings and foundations - Concrete floor slabs supported directly on the ground shall be not less than 3½ inches (89 mm) thick (IBC §1907.1). - For Group R-3 occupancies and buildings of other occupancies less than two stories above grade plane of light-frame construction, plain concrete footing thickness is permitted to be 6 inches, provided the footing does not extend more than 4 inches on either side of the supported wall (IBC §1906.1). - Anchor bolts attaching wood sill plates to foundations must be embedded a minimum of 7 inches (178 mm); maximum nominal diameter ⅝ inch in light-frame wood structures (IBC §1905.1.8). - Footings must be poured on undisturbed or well-compacted earth; do not fill…

Key Concepts

Materials and standards - Brick grades: Grade SW is highly resistant to frost action (foundation courses, retaining walls); MW for exposure below freezing but not likely permeated with water; NW for interior backup masonry (Modern Masonry 9th ed., p. 116). - A solid masonry unit has a net cross-sectional area in every plane parallel to the bearing surface of 75% or more of gross area; cored brick still qualifies if holes are under 25% (Modern Masonry, p. 123). - Unstabilized adobe: average compressive strength 300 psi, no individual unit below 250 psi (IBC 2021 §2109.2.1.1); moisture content not exceeding 4 percent by weight (§2109.2.1.3). - Surface-bonding mortar: ASTM C887 (IBC §2103.2.2). Adhered manufactured stone veneer units: **ASTM…

Key Concepts

Pre-erection activities and site readiness - Before steel erection begins, the steel erector must receive written notification that the concrete in footings, piers and walls has attained either 75 percent of the intended minimum compressive design strength (based on an appropriate ASTM field-cured sample test method) or sufficient strength to support the loads imposed during steel erection — 29 CFR 1926, Subpart R, §1926.752(a)(1) and (b). - Job planning is the responsibility of the owner's designated representative for design (ODRD), working with the owner's designated representative for construction (ODRC), who answers to the owner for overall construction, planning, quality and completion and is usually the general contractor or construction manager on site — *Study Guide for Commercial…

Key Concepts

Studs, plates and notching - Studs shall be a minimum No. 3, standard or stud grade lumber; bearing studs not supporting floors and nonbearing studs are permitted to be utility grade where spaced per Table R602.3(5) (IRC R602.2). - Studs shall be continuous from support at the sole plate to a support at the top plate; exception for jack, trimmer and cripple studs at openings complying with Tables R602.7(1) and R602.7(2) (IRC R602.3). - In exterior walls and bearing partitions, a wood stud shall not be cut or notched in excess of 25 percent of its depth. The 40 percent limit applies to nonbearing partitions (IBC 2308.5.9). - End joints in double top plates on bearing and…

Key Concepts

Gypsum board fastening and thickness - Type-X gypsum board on a garage ceiling beneath a habitable room: install perpendicular to ceiling framing, fastened at maximum 6 inches on center with minimum 1-5/8 inch 6d coated nails or equivalent drywall screws (IBC 2021, Ch. 25, Table 25.06.1). - Ceilings receiving a water-based texture on 24-inch o.c. framing: minimum board thickness increases from 1/2 inch to 5/8 inch, or use 1/2-inch sag-resistant gypsum ceiling board; apply perpendicular to framing (Table 25.06.1 notes). - Horizontal diaphragm ceilings: fasteners spaced not more than 7 inches on center at all supports, including perimeter blocking, and not more than 3/8 inch from the edges and ends (IBC 2508.6.4). IRC Table R702.3.6, note d…

Key Concepts

Minimum slopes - Asphalt shingles: slopes of 2 units vertical in 12 (2:12) or greater; from 2:12 up to 4:12 double underlayment is required — IRC 2021/2018 R905.2.2. - Strip (three-tab) shingles are installed on roofs with a slope of 4-in-12 or greater; 4-in-12 or greater is the "high slope" category. Lower slopes require the manufacturer's literature for special installation advice — Carpentry and Building Construction, Sec. 22.1/22.2. - Metal roof panels (IRC 2018 R905.10.2): 3:12 for lapped, nonsoldered seams without lap sealant; 1/2:12 (4 percent) for lapped, nonsoldered seams with applied lap sealant; 1/4:12 (2 percent) for standing-seam systems.

Key Concepts

Fixture counts (IBC 2021, Section 2902.1.1). To determine the occupant load of each sex, divide the total occupant load in half, then apply the Table 2902.1 ratio for each fixture type. Fractional numbers resulting from the ratios shall be rounded up to the next whole number; for calculations involving multiple occupancies, the fractional numbers for each occupancy shall first be summed and then rounded up. - Exception 1: the total occupant load is not required to be divided in half where approved statistical data indicates a distribution of the sexes other than 50 percent of each sex. - Exception 2: where multiple-user facilities are designed to serve all genders, the minimum fixture count is calculated at **100…

Tennessee BC Combined Residential/Commercial/Industrial Contractor — 3 questions (3% of exam)

Key Concepts

Equipment sizing and installation - Heating and cooling equipment and appliances shall be sized in accordance with ACCA Manual S based on building loads calculated in accordance with ACCA Manual J or other approved heating and cooling calculation methodologies — Section M1401.3 (IRC, Page 14-1). - Equipment and appliances supported from the ground shall be level and firmly supported on a concrete slab or other approved material extending not less than 3 inches above the adjoining ground — Section M1305.1.3.1 (IRC, Page 13-2). - Supply air ducts connecting to listed central heating furnaces shall have the same minimum clearance to combustibles as required for the furnace…

Key Concepts

Emergency and standby power (IBC Chapter 27) - Emergency power systems must 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 2021, 2702.1.4). - Emergency and standby power systems must provide the required power for a minimum duration of 2 hours without being refueled or recharged, unless specified otherwise (2702.1.5). - Stationary emergency and standby generators required by the code shall be listed in accordance with UL 2200 (2702.1.1). - Fuel lines supplying a generator set inside a high-rise building shall be separated from other areas by a UL 1489-tested fire-resistant pipe-protection system rated not less than 2 hours, or an…

Key Concepts

Fall protection - Each employee on a walking/working surface with an unprotected side or edge 6 feet or more above a lower level must be protected by guardrail systems, safety net systems, or personal fall arrest systems — §1926.501(b)(1). The same 6-foot trigger applies to residential construction under §1926.501(b)(13), which also lists scaffolding as an acceptable means. - Guardrail top rails must withstand, without failure, a force of at least 200 pounds (890 N) applied within 2 inches of the top edge in any outward or downward direction, at any point along the top edge — §1926.502(b)(3). Midrails and intermediate members carry a 150-pound requirement under §1926.502(b)(5). Top rail height: 39–45" (1926.502).