How to Calculate Paint and Labor Costs for Your Next Interior Renovation

A fresh coat of paint is one of the highest ROI (Return on Investment) improvements you can make to a home. However, estimating the true cost of a professional paint job involves more than just picking a color at the hardware store.

Measuring the Surface Area

To accurately estimate materials, you must first calculate the total wall surface area. Measure the perimeter of the room and multiply it by the ceiling height. While professionals often subtract the square footage of doors and windows, a safer DIY approach is to leave them in the calculation to serve as your "waste factor" for touch-ups.

Gallons and Coverage Rates

A standard gallon of high-quality interior paint covers approximately 350 to 400 square feet. However, a professional finish almost always requires two coats.

• Calculate Total Coverage: (Surface Area) × (2 Coats)
• Calculate Gallons: Total Coverage ÷ 350

If you are painting over a dark color with a lighter one, you may need to factor in a coat of primer, which adds to the material cost.

The True Cost of Labor

While the paint itself is relatively inexpensive, labor is the primary cost driver. A professional painting crew spends a significant portion of their time doing prep work: taping edges, laying drop cloths, spackling holes, and sanding walls.

As a rule of thumb, labor for interior painting usually costs twice as much as the materials. If you spend $300 on premium paint and supplies, expect the labor to cost around $600, bringing the total project cost to $900. Intricate trim work or high ceilings will push this ratio higher.