Painting Estimate Basics: How to Calculate Paint, Primer, and Labor

Why Painting Bids Go Wrong

Painting looks straightforward until you factor in coverage rates, number of coats, surface prep, cut-in labor, and ceiling work. Miss any of these and your margin disappears.

Step 1: Calculate Paintable Square Footage

For walls: perimeter × ceiling height, minus doors (approx 21 sqft) and windows (approx 15 sqft each).

For ceilings: length × width.

For trim and doors: count pieces and use standard sqft per unit.

Step 2: Calculate Gallons Needed

Standard paint coverage: 350–400 sqft per gallon (one coat, smooth surface).

Divide your paintable sqft by 350. Multiply by number of coats:

New drywall (bare): 1 coat primer + 2 coats paint

Previously painted, same color: 1–2 coats

Dark to light or color change: 2–3 coats

Step 3: Account for Surface Prep

Prep labor is often 30–40% of total painting labor. It includes:

Patching nail holes and drywall damage

Sanding glossy surfaces

Masking and taping

Priming new or repaired areas

Step 4: Labor Rates (2026)

Interior walls and ceilings: $1.50–$2.50/sqft painted

Trim and doors: $25–$60 per door, $1.00–$2.00 per linear foot for trim

Specialty finishes (faux, texture): $3.00–$6.00/sqft

VegaEstimating.ai Paint Module

Vega calculates paint gallons, primer, coats, and labor automatically — including wall area deductions for doors and windows — from your uploaded floor plan.