How Much Wallpaper Do I Need? Double Rolls, Pattern Repeat, and Two Worked Examples

Ordering wallpaper is the one step where a small mistake costs real money. Order one roll short and you wait weeks for a reorder that may come from a different dye lot. Order three too many and you own $600 of paper you cannot return.

This guide shows the math we use, in plain steps, and explains why the "square footage divided by 56" method in most online calculators is the reason people run short. If you would rather not do the math, our free measure and estimating service is at the end. Our wallpaper installation page explains how an install works, and current labor ranges are on the pricing page.

Start with the roll

Most wallpaper in the United States is sold as a double roll. Brewster Home Fashions specs a typical non-woven double roll at 20.5 inches wide by 33 feet long, "covering approximately 56.4 square feet per roll." European rolls are 52 centimeters by 10 meters, also about 56 square feet. Older American single rolls are 27 inches by 27 feet.

Two catches. First, some products are sold as single rolls. Tempaper's peel-and-stick, for example, is 20.5 inches by 16.5 feet, about 28 square feet, per roll. Second, that 56 square feet is the paper on the roll, not the paper that ends up on your wall. Trimming and pattern matching eat into it.

Always read the label. Width and length matter more than the square-foot number.

Why square footage alone under-orders

Lowe's online calculator takes your wall lengths and ceiling height, divides by 56 square feet per roll, and gives you a number. It ignores pattern repeat entirely. Milton & King's measuring guide puts it in capital letters: "DO NOT USE SQUARE FOOTAGE WHEN CALCULATING HOW MUCH WALLPAPER TO PURCHASE."

Here is why. Wallpaper goes up in vertical strips. Every strip is cut a few inches longer than the wall for trimming at the ceiling and baseboard. And if the paper has a pattern, every strip has to start at the same point in the pattern so the design lines up across the seam. So each strip is cut to a multiple of the repeat, not to the wall height, and the leftover is waste you paid for.

The real question is not "how many square feet" but "how many strips, and how many strips fit on one roll."

Pattern repeat and match type

Pattern repeat is the vertical distance before the design starts over. Wikipedia defines it as the smallest rectangle that can be tiled to form the whole pattern. It is printed on the label in inches: 12, 18, 21, 24, 25.25, and so on.

Match type tells you how the pattern lines up from strip to strip. York's hanging instructions list three:

• Random match. No alignment needed. Grasscloth, most textures, some stripes. Least waste.
• Straight match. The pattern lines up at the same height on every strip. Moderate waste.
• Drop match. The next strip starts partway down the repeat. In a half-drop, Wikipedia's example, a 24-inch repeat means the second strip begins 12 inches down. Spoonflower's calculator adds half the repeat to the wall height before rounding up. Most waste.

The bigger the repeat and the more complex the match, the more paper the same wall needs.

The strip method, step by step

1. Measure the total width of the walls you are papering, in inches. Include doors and windows; you still need strips above and below them and the pattern has to carry across.
2. Divide by the roll width (usually 20.5 inches). Round up. That is your strip count.
3. Measure wall height in inches and add 4 inches for trim.
4. Round that up to the next multiple of the pattern repeat. For a drop match, add half the repeat first, then round. That is your cut length.
5. Divide the roll length (usually 396 inches for a 33-foot roll) by the cut length. Round down. That is strips per roll.
6. Divide strips by strips per roll. Round up. That is your roll count.
7. Add 10 to 15 percent for overage, and one extra roll if you want a repair spare from the same dye lot.

Worked example 1: 12-by-12 bedroom, 9-foot ceilings

Paper: standard non-woven, 20.5 inches wide, 33-foot double roll, 24-inch repeat, straight match.

Now the square-footage method: 432 square feet of wall, minus a door and a window, is about 396. Divide by 56 and you get 7.1, so the calculator says 8 rolls. That is two to three rolls short, and a wall that stays half done until the reorder arrives.

For a drop match with the same 24-inch repeat, Spoonflower's rule adds 12 inches to the wall height first: 108 + 12 + 4 = 124, rounded up to 144 inches. Now only two strips fit on a 33-foot roll, and the calculator answer for the same room jumps to 15 rolls. A careful installer can often trim that by alternating where each strip is cut from, but you should budget for the higher number. That is why we ask about match type before we quote a roll count.

Worked example 2: powder room, 6 by 6 feet, 9-foot ceilings

Same paper as above.

Square-footage method: 216 square feet minus a door is about 195, divided by 56 is 3.5, so 4 rolls. One short. The short strips around the mirror, vanity, and toilet are exactly where the extra roll goes.

Murals and panels

Murals come as numbered panels sized to a wall, so the math is different and simpler.

Spoonflower's guidance is to divide the wall width by 24 inches and round up to get the panel count. Milton & King's murals ship in sets of panels each 130 inches tall by 24 inches wide; its product page says to "divide your total wall width in inches by 144" to get the number of sets, and a six-panel set covers about 10.8 feet wide by 12.1 feet tall. Chasing Paper sells panels in 2-by-4, 2-by-8, and 2-by-12-foot sizes and its calculator adds 15 percent overage.

The important detail with murals is height. If your wall is taller than the panel, you cannot add a piece at the top; you need a taller panel size or a custom print. Measure to the highest point, including any slope.

Overage: how much extra, and why

Order 10 to 15 percent more than the strip count says. Chasing Paper builds 15 percent into its calculator; Spoonflower offers 10 percent as an option. That covers a miscut, a flaw in the roll, a damaged strip, and pattern loss at corners.

Then keep one full roll afterward. Wallpaper is dyed in lots, and a roll ordered two years from now to fix a scuff may not match. The spare roll is your insurance.

Or let us measure

Most people do not want to do this math, and most do not need to. Send us three photos and your wall dimensions along with the paper you are considering (brand, roll size, repeat, match type), and we will send back a roll count and a labor ballpark at no charge. If you book a Design Session, we measure in person, confirm the count against the actual label, and order through trade accounts where we can.

Our labor for standard paper starts at $7–$10 per square foot as a ballpark; we confirm after we see the walls. We would rather you spend $100 on a spare roll than $500 on a rush reorder.

FAQ

How many square feet does a double roll of wallpaper cover? About 56 square feet on the roll, per Brewster's spec of 20.5 inches by 33 feet. On the wall, after trimming and pattern matching, plan on 40 to 45 usable square feet for a patterned paper.

What is a drop match? A pattern where each new strip starts partway down the repeat so the design steps diagonally. A half-drop with a 24-inch repeat starts the next strip 12 inches lower. It looks great and uses more paper.

Do I subtract doors and windows? Not for standard openings. You still need strips above and below them, and the pattern has to carry across. Only subtract a very large opening like a sliding-door wall.

How much extra wallpaper should I order? Ten to 15 percent, plus one spare roll from the same dye lot for future repairs.

Will you calculate rolls for paper I bought online? Yes. Send us the label photo with your wall dimensions and we will check it before you order more.

Let's make sure you order the right amount

Send us three photos and your wall dimensions, plus the paper's label, and we will send a roll count and a written labor ballpark. Or book a route-friendly time online for a Design Session and we will measure in person. Call or text 801-895-3794. Serving Salt Lake City, Provo, Ogden, Park City, Midway, and Tooele.

Sources

• Brewster Home Fashions, roll specifications — https://www.brewsterwallcovering.com/
• Wikipedia, "Wallpaper" (roll sizes, pattern repeat, drop match) — https://en.wikipedia.org/wiki/Wallpaper
• Tempaper, Textured Faux Grasscloth product page (roll dimensions) — https://tempaper.com/products/textured-grasscloth-peel-stick-wallpaper
• Lowe's, wallpaper calculator — https://www.lowes.com/n/calculators/wallpaper-calculator
• Milton & King, "How Many Wallpaper Rolls Do I Need?" measuring guide — https://www.miltonandking.com/blog/how-many-wallpaper-rolls-do-i-need-how-to-measure-the-room/
• Milton & King, Oriental Garden Mural product page (panel math) — https://www.miltonandking.com/product/oriental-garden-mural/
• York Wallcoverings, "How to Hang Wallpaper" (match types) — https://www.yorkwallcoverings.com/pages/how-to-hang-wallpaper
• Spoonflower, wallpaper calculator — https://www.spoonflower.com/en/wallpaper-calculator
• Chasing Paper, Fresh Cut product page (panel sizes and overage) — https://chasingpaper.com/products/fresh-cut