Finishes (Drywall, Flooring, Painting, and Coatings)
Gypsum board
Thickness and type drive performance: 5/8-inch Type X for rated assemblies, moisture-resistant board in wet areas. Fastener spacing and type, framing spacing, and treatment of joints all affect the finished appearance, which is graded by the five levels of finish in GA-214. Level 4 is the default for painted surfaces; Level 5 is specified for critical lighting, gloss paints, or shallow-angle viewing.
Flooring
Slab moisture testing is the most commonly missed step: ASTM F2170 in-situ relative humidity probes for resilient and wood flooring, with older calcium chloride tests still cited in some specifications. Wood flooring needs acclimation and expansion gaps, subfloors need flatness within tolerance, and tile follows ANSI A108 with thin-set or medium-bed mortar over a substrate stiff enough for the specified deflection, often L/360, plus crack-isolation membrane where required.
Painting and coatings
Surface preparation, primer selection, and dry-film thickness in mils drive performance - wet thickness means nothing. VOC limits, sheen, and the number of coats come from the specification and the manufacturer's data sheet.
Traps
Assuming Level 4 is acceptable everywhere; skipping moisture testing and blaming the flooring; painting over damp or dusty substrates; and counting coats on a color hide rather than on mil thickness.
Rule of thumb: finish level, moisture test method, and dry-film thickness are all specified numbers - read the section before assuming any default.