Master the Measure: How to Correctly Calculate Wallpaper for Your Project

Precision is Power: How to Correctly Calculate Wallpaper

Embarking on a wallpaper project, whether it's a dramatic accent wall or an entire room transformation, is exciting! But before you fall in love with a pattern, the first and most critical step is accurate measurement. Incorrect calculations can lead to frustrating delays, unnecessary waste, or worse – running out of wallpaper mid-project.

Measuring for wallpaper isn't just about length times width; it involves understanding roll sizes, pattern repeats, and accounting for various architectural features. Don't worry, it's not as daunting as it sounds! This guide will walk you through the process, helping you order precisely what you need for a flawless installation.

Tools You'll Need:

Before you begin, gather these essentials:

• Steel Measuring Tape: Long and sturdy, preferably one that locks.

• Pencil & Notepad: For jotting down measurements.

• Ladder or Step Stool: For reaching high spots safely.

• Calculator: To do the math easily.

• Your Chosen Wallpaper Roll Information: You'll need the width and length of the roll, and most importantly, the pattern repeat (usually found on the product specifications or label).

Step-by-Step Guide to Measuring Your Walls:

Step 1: Measure the Height and Width of Each Wall

• Height: Measure the height of each wall from the baseboard to the ceiling. Important: Take measurements at several points across the wall (e.g., left, middle, right). Use the longest measurement you find for that wall, as walls are rarely perfectly uniform.

• Width: Measure the total width of each wall.

• Record Everything: Write down each wall's individual height and width clearly.

Step 2: Calculate the Total Square Footage of Your Walls

• For each wall, multiply its height by its width to get the square footage (Height x Width = Square Footage).

• Add up the square footage of all the walls you plan to wallpaper to get your total square footage.

Step 3: Account for Openings (Windows, Doors, etc.)

• Measure Major Openings: Measure the height and width of any significant openings like windows, doors, or built-in cabinets. Calculate their square footage.

• Partial Deduction: While you will deduct these areas from your total wall square footage, do not deduct the full amount. You'll still need wallpaper to cut around these features. A good rule of thumb is to deduct only half the square footage of major openings (e.g., a standard door or window). Smaller openings (like electrical outlets or small wall sconces) should not be deducted at all.

Step 4: Understand Wallpaper Roll Dimensions

Wallpaper is typically sold in single rolls or double rolls. However, manufacturers often list the material in double rolls for pricing, even if they are physically shipped as single rolls.

• Check the Square Footage Per Roll: The product specifications will tell you the exact square footage contained within one (or one double) roll. This is crucial for your calculations.

  • Example Standard Double Roll: A common double roll might be 20.5 inches wide by 33 feet long, covering approximately 56 square feet.

Step 5: Factor in Pattern Repeat (The Most Critical Step!)

This is where many DIYers make mistakes. The pattern repeat is the vertical distance between one point on a pattern and the next identical point. This ensures the design lines up seamlessly from one strip to the next.

• How it impacts: You'll need extra length for each strip to match the pattern, leading to some waste.

• Calculation Tip: For each vertical strip of wallpaper, you'll need to add at least one full pattern repeat to its height.

  • Simple Rule of Thumb: If your wall height is 8 feet and your pattern repeat is 24 inches (2 feet), you'll need at least 10 feet for each strip to allow for matching and trimming.

• Adjust Total Square Footage: To account for pattern repeat, some experts suggest adding an additional 15-20% to your total calculated square footage, especially for large patterns. Alternatively, work with the number of drops you can get per roll (see Step 6).

Step 6: Calculate How Many Rolls You Need

Here's a common method that accounts for drops and pattern repeat:

1. Calculate Number of Strips Per Wall: Divide the wall's total width (in inches) by the wallpaper roll's width (in inches). Round up to the next whole number.

   • (Example: 144" wall width / 20.5" roll width = 7.02 -> You need 8 strips for that wall)

2. Calculate Usable Length Per Roll: Determine how many full drops you can get from one roll after factoring in the pattern repeat.

   • Roll Length (e.g., 33 ft) / (Wall Height + Pattern Repeat (e.g., 8ft + 2ft = 10ft)) = Number of usable drops per roll.

3. Calculate Rolls Per Wall: Number of Strips Per Wall / Number of Usable Drops Per Roll. Round up to the next whole number.

4. Total Rolls: Sum the rolls needed for each wall.

Step 7: The "Golden Rule" – Always Order Extra!

Even with perfect measurements, waste is inevitable due to trimming, pattern matching, and potential errors.

• Standard Buffer: Always add at least 10-15% extra to your final roll count.

• Why Extra? It accounts for:

  • Minor cutting mistakes

  • Pattern matching nuances

  • Future repairs (in case a section gets damaged)

  • Differing dye lots (it's best to have all rolls from the same dye lot to avoid subtle color variations).

Tips for Tricky Areas:

• Corners: Measure each side of a corner as a separate wall. Don't wrap a full strip around an outside corner unless specifically instructed by the manufacturer.

• Arches/Sloped Ceilings: Measure the maximum height and width, then calculate the square footage of the entire area. Overestimate rather than underestimate for these complex cuts.

• Doors & Windows: As mentioned, deduct only partially. Remember you'll need to cut around them, and some smaller pieces might still be needed for above/below the opening.

When to Call a Professional: For Peace of Mind & Flawless Results

While measuring your own walls for wallpaper installation is certainly doable, it can be complex, especially with intricate patterns, high ceilings, numerous architectural features, or specialized materials like custom murals, wood veneers, or acoustical wallcoverings.

For guaranteed accuracy, minimal waste, and a truly flawless finish, consider engaging a professional wallpaper installer. They bring years of experience in precise measurement and installation techniques, ensuring your project looks exactly as you envision without the stress.

Precision Paves the Way to Beautiful Walls

Accurate measurement is the cornerstone of any successful wallpaper project. By taking the time to measure correctly and understanding the nuances of pattern repeat and roll dimensions, you'll be well on your way to transforming your space beautifully and efficiently.

Ready to select your dream wallcovering and need expert measurement or installation services? Contact The Wallpaper Company today for a personalized consultation!