How to measure flooring for a project

Room-by-room measuring plus the right waste factor prevents shortages and overbuying.

Flooring estimates start with accurate area, but the most reliable way to measure is room-by-room. Measure each room (including closets and hallways if they will be floored), break odd shapes into simple rectangles, and add everything together to get your total area. Write measurements down as you go and sketch the layout so you do not miss small spaces like pantry closets and long hallways. Use finished dimensions (wall-to-wall), not rough framing.

After area, your biggest swing factor is waste. Waste is driven by layout choices (board direction, borders, and patterns like herringbone), room complexity (corners, doorways, and notches), and the product itself (plank length/width and the manufacturer's box coverage). The more cut-heavy the project, the less you can reuse offcuts, even if your area math is perfect. If you are changing direction between rooms or adding a picture-frame border, plan extra waste.

Measuring checklist

Measure each space using finished dimensions (wall-to-wall). If a room is an L-shape, split it into rectangles and add them. If you have many doorways or angles, a quick sketch with labeled dimensions prevents missed sections. Measure closets and alcoves separately so they do not get skipped.
Add all areas (rooms, closets, and hallways). Keep units consistent (sq ft or sq m) so you do not accidentally mix measurements. Convert once and stick to a single unit system for the whole project.
Use the manufacturer's stated coverage per box for your exact product. Box coverage varies by thickness and packaging, and you almost always must buy whole boxes. If you are comparing products, box coverage differences can be bigger than the difference between two waste factors. Check the label coverage, not just plank dimensions.
Apply waste before converting to boxes, then round up. If matching later might be difficult, consider keeping 1-2 extra boxes for repairs and future color/lot matching. Inspect boards early so you can exchange defects before you install.

Picking a waste factor

A common range is 5-15%, but it should match your layout. Around 5% can work for large, simple rectangles with a straight install and minimal cut-outs. Around 10% is safer for multiple rooms, many doorways, narrow hallways, and lots of short cuts. 15%+ is common for diagonal installs, herringbone, and other pattern layouts that create offcuts you cannot reuse. Plank length and room width interact too: short planks or a room that forces lots of small end pieces can raise waste even with a straight layout. If you have to maintain a specific stagger pattern across multiple rooms, waste can also increase. If the product may be discontinued or lot-matching matters, extra material is often cheaper than trying to match later. When in doubt, add a little more and keep a sealed box for future repairs.

Flooring measurement tips

Flooring estimates often fail on waste. Room shape, plank direction, and obstacles can push waste higher than typical ranges, especially with wide planks or diagonal installs.

Always base boxes on the manufacturer’s coverage per box (not just plank dimensions), and consider underlayment, transitions, and trim as separate line items.

Increase waste for diagonal layouts and many small rooms/closets.
Plan extra for pattern matching if you’re using decorative layouts.
Keep a small number of spare planks for future repairs.

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Flooring waste factor (practical)

Waste is driven by layout and cuts, not just square footage. Pick a waste range that matches your room and install pattern.

Layout	Typical waste	Why it changes
Simple rectangles	5–8%	Few closets/angles
Typical homes	8–12%	Hallways/closets/obstacles
Many small rooms	12–15%	Short runs and more cuts
Diagonal/patterns	15–20%+	Offcuts reuse poorly

Example: 520 sq ft room at 10% waste ⇒ buy for ~572 sq ft, then convert to whole boxes using the product label coverage.

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FAQ

Why do I need a waste factor?

You lose material to end cuts, notches, damaged boards, and defects. Even with a perfect area measurement, you will create offcuts that are too short to reuse. You also usually have to buy whole boxes, so rounding decisions matter. A small surplus makes future repairs easier, because matching color/texture later is often the hardest part. Waste is cheaper than a second trip or a mismatched lot.

Should I include closets?

Usually yes-measure them like any other space if the flooring will run into the closet. Closets and small rooms are cut-heavy, which is another reason waste matters. Only exclude areas you are sure will not be floored (for example, a built-in island that will remain in place). If you are changing direction between rooms, closets can also force extra transitions and cuts. If a closet uses a different product, estimate it separately.

What if my rooms are not perfect rectangles?

Split the shape into rectangles (and triangles if needed), measure each piece, and add them. This is usually more accurate than guessing one overall dimension. For curved edges, measure a conservative rectangle that covers the curve and treat the extra as part of your waste buffer. If the curve is important, make a simple cardboard template and approximate the area by segments.

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