Flooring & Tile guide

How to Measure a Room for Flooring

Measure room square footage correctly before adding flooring waste and rounding to full boxes.

Quick answer

For a rectangular room, multiply length by width. For L-shaped or irregular rooms, split the floor into rectangles, calculate each area separately and add the results.

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Step by step

  1. Sketch the room. Mark closets, alcoves and unusual shapes.
  2. Measure each section. Use the same unit for every dimension.
  3. Calculate area. Multiply length × width for each rectangle.
  4. Add sections. Combine the measured areas before applying waste and box rounding.

Formula or rule of thumb

room area = sum of each rectangular section's length × width

Example

A 12 × 10 ft room plus a 3 × 4 ft closet is 120 + 12 = 132 ft² before waste.

Common mistakes

Common errors include forgetting closets, measuring wall-to-wall in mixed units, and rounding each small section separately instead of totaling the measured area first.

Planning note: product yields, installation methods, site conditions and local requirements can change the final quantity. Use the exact manufacturer or supplier information before purchasing.

FAQ

Do I include closets?

Include closets when they will receive the same flooring.

Should I subtract cabinets?

Only subtract fixed areas that definitely will not receive flooring.

When do I add waste?

Add waste after calculating the total measured floor area and before box rounding.

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