Tennessee BC-C Industrial Contractor

Direct construction costs are the labor, material and equipment tied to a specific trade or phase (pipe materials, backhoe rental, pipe bedding aggregate), while direct (job) overhead covers administrative items caused by the particular job but not tied to a trade or phase, such as traffic control (barricades, flaggers, lane delineators) and pipe/soil density testing.

A contact splice places the bars in actual contact and is preferred because it provides more strength, while a spaced-lap splice sets the bars apart without contact at a center-to-center spacing that must not exceed 6 inches.

B-B Plyform®, sanded both sides and mill oiled, can be reused 5 to 10 times, whereas an HDO-overlaid surface normally produces 20 to 50 reuses or more with reasonable care.

Lumber beam sides require 2x4 vertical cleats on 2' to 2'-6" centers, while plywood sides eliminate the cleats and use 2x4 vertical stiffeners instead.

Field-cured samples stay on site under the same conditions as the placement and may be used to determine when it is safe to remove forms, while acceptance strength is determined from laboratory-cured cylinders tested under ASTM C39.

The registered design professional must show on the construction documents the joist/joist girder designations and requirements for design, layout, end supports, anchorage, bridging design differing from SJI, bridging termination connections and bearing connections resisting uplift and lateral loads; the manufacturer designs the joists for those stated loads and, when required, submits sealed calculations plus bridging design differing from SJI and connection design for connections differing from SJI, field splices and joist headers.

Each end of a "K" series joist requires a minimum of two 1/8-inch fillet welds 1 inch long (or two 1/2-inch bolts or the equivalent), while the larger 1/4-inch by 2-inch welds apply to "LH" and "DLH" series joists and joist girders.

Non-standard products — barrel, bowstring, gable and scissor joists and other special truss configurations — are not standard SJI products and must be erected per AISC Code of Standard Practice Section 7 and OSHA 1926.756 rather than typical SJI erection procedures.

A bent is a section of vertical structure usually assembled from fabricated members at the site and requires temporary bracing until all permanent members are attached, while a truss provides horizontal and vertical strength and is usually shop-fabricated and shipped to be lifted into place as a unit.

A hollow unit has net cross-sectional area less than 75 percent of its gross cross-sectional area measured in any plane parallel to the surface containing voids; a solid unit has 75 percent or more.

Solid-core construction (wood strips, particleboard, rigid foam or other core covered with a thin veneer) reduces warping, is more fire-resistant and is generally preferred for exterior doors, unlike hollow-core doors.

Marking hard costs up by the overhead percentage under-recovers overhead (10% markup on $90 = $99), while dividing the hard cost total by (1.0 − desired margin) yields the correct selling price ($90 ÷ 0.90 = $100, a true 10% margin).

Type II(MH) generates heat at a slower rate by limiting the heat index (C₃S + 4.75 C₃A) to a maximum of 100 for mass elements, while Type V is the sulfate-resistant cement used only where severe sulfate action from high-alkali water and/or soil occurs (Type II offers only moderate sulfate resistance).