THE BASICS
1. What counts as trim
Trim paint — enamel — covers doors, baseboards, casings, crown molding, railings and cabinets. These surfaces take abuse, so enamels are formulated for hardness and a uniform sheen even after cleaning.
FIGURES
2. Enamel coverage per gallon
Our practical reference for interior enamel is 375 sq ft per gallon per coat, in line with Sherwin-Williams ProClassic data. Enamels are often brushed or rolled on thin for leveling, so real coverage can dip on hot days or very porous wood.
| Container | Approx. coverage | Typical use |
|---|---|---|
| Quart | ≈ 94 sq ft | One room of trim, 1–2 coats |
| Gallon | ≈ 375 sq ft | 3–4 interior doors, both sides, 2 coats |
| 5-gallon pail | ≈ 1,875 sq ft | Whole-house trim in one go |
ProClassic (Sherwin-Williams) declares ~375–425 sq ft/gal depending on sheen; use 375 to plan.
MEASURING
3. Measuring doors and trim without losing your mind
A standard slab door is about 3×6.67 ft: 20 sq ft per side, 40 sq ft for both sides. Baseboards: run a tape along the wall and multiply linear feet by the height in feet — a 3-inch baseboard along 100 ft of wall is only 25 sq ft.
Cabinets count front frames plus exposed sides; drawers and shaker panels add area through their grooves, so add about 10% for them.
SHOPPING
4. How much to buy
A typical 12×12 room with two doors, 60 ft of baseboard and casings holds around 150 sq ft of trim: one quart per coat, two coats from a half gallon. A whole-house trim refresh usually fits in 2–3 gallons.
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