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Room finish estimator

Turn room dimensions into paint, flooring, tile, or drywall purchase units, with coverage, coats, and waste shown as separate assumptions.

HS TOOL / 04

Estimate finish materials.

Measure net area, add coats or waste, and round to whole purchase units.

Formula and assumptions: walls use 2 × (length + width) × height; floors use length × width. Openings are subtracted, coats and waste are applied, and purchase units round upward.

RESULTEnter the measurements to calculate.
Source: EPA lead-safe renovation planning ↗

COMMON WAYS TO ASK

QUICK ANSWER

What this calculator tells you.

Turn room dimensions into purchase units with the coverage, coats, and waste allowance stated rather than hidden. The area is the easy part; the rounding is where projects go wrong.

WORKED EXAMPLE

Painting a 12 by 15 foot room

INPUT8 ft ceiling · two coats · 350 sq ft per gallon
RESULTPurchase units with waste and coats shown separately
CHECK THE EDGE CASES

Questions people ask next.

Why does the estimate exceed the area I measured?

Coverage ratings assume ideal application, cuts waste material, and most finishes need more than one coat. Those three factors are shown as separate inputs so you can adjust each to your own job.

Should I subtract windows and doors?

Enter them as openings. For paint it usually matters; for flooring, small subtractions are often absorbed by waste anyway, which is why the waste percentage stays visible.

CONTINUE CALCULATING

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