Wallpaper Roll Calculator
Estimate how many rolls of wallpaper you'll need for your room. This calculator accounts for room dimensions, wallpaper roll size, pattern repeat, and a waste factor.
Enter 0 if there is no pattern repeat.
Typically 10-20% for cutting and matching.
Understanding Wallpaper Calculation
Wallpapering a room can dramatically transform its look, but getting the right amount of wallpaper is crucial. Too little, and you'll face delays; too much, and you've wasted money. Our Wallpaper Roll Calculator helps you accurately estimate your needs, taking into account all the critical factors.
Key Factors in Wallpaper Calculation
Several variables influence how much wallpaper you'll need. Understanding these will help you measure accurately and interpret the calculator's results:
1. Room Dimensions
- Room Length and Width: These determine the perimeter of your room, which is the total length of wall you need to cover.
- Room Height: This dictates the length of each individual strip of wallpaper.
- Note: For simplicity, this calculator assumes a standard rectangular room and does not deduct for doors or windows. It's generally recommended to include these areas in your initial calculation and rely on the waste factor to cover any minor overestimation, as cutting around openings still requires material.
2. Wallpaper Roll Dimensions
- Roll Width: Standard wallpaper rolls come in various widths (e.g., 20.5 inches, 21 inches, 27 inches). This affects how many vertical strips you can get across the room's perimeter.
- Roll Length: The total length of wallpaper on a single roll (e.g., 33 feet, 16.5 feet for double rolls).
3. Pattern Repeat
If your wallpaper has a pattern, you'll need extra material to ensure the design aligns seamlessly from one strip to the next. The "pattern repeat" is the vertical distance before the pattern repeats itself. The calculator accounts for this by adding extra length to each strip to allow for matching.
4. Waste Factor
It's always wise to order a little extra wallpaper. A waste factor (typically 10-20%) accounts for:
- Mistakes during cutting or hanging.
- Damage to a strip.
- Trimming excess at the top and bottom of walls.
- Future repairs (it's good to have a leftover roll from the same dye lot).
- Complex room features (e.g., alcoves, irregular walls, many windows/doors).
How to Use the Calculator
- Measure Your Room:
- Measure the length of each wall and add them together for the total perimeter, or simply measure the room's length and width.
- Measure the height of your walls from floor to ceiling.
- Check Wallpaper Specifications:
- Find the roll width, roll length, and pattern repeat (if any) on the wallpaper packaging or product description.
- Input Values: Enter these measurements into the respective fields in the calculator.
- Adjust Waste Factor: A default of 10% is provided, but you can adjust it based on your experience and the complexity of the pattern or room.
- Click "Calculate": The calculator will provide an estimated number of rolls needed.
Example Calculation
Let's say you have a room with the following dimensions:
- Room Length: 12 feet
- Room Width: 10 feet
- Room Height: 8 feet
And your chosen wallpaper has these specifications:
- Roll Width: 21 inches
- Roll Length: 33 feet
- Pattern Repeat: 21 inches
- Waste Factor: 10%
Here's how the calculation works:
- Room Perimeter: 2 * (12 ft + 10 ft) = 44 feet
- Wallpaper Roll Width (in feet): 21 inches / 12 = 1.75 feet
- Number of Strips Needed: Ceiling(44 ft / 1.75 ft) = Ceiling(25.14) = 26 strips
- Pattern Repeat (in feet): 21 inches / 12 = 1.75 feet
- Length Per Strip (accounting for pattern repeat): Ceiling(8 ft / 1.75 ft) * 1.75 ft = Ceiling(4.57) * 1.75 ft = 5 * 1.75 ft = 8.75 feet
- Total Wallpaper Length Required: 26 strips * 8.75 feet/strip = 227.5 feet
- Raw Rolls Needed: 227.5 feet / 33 feet/roll = 6.89 rolls
- Rolls with Waste Factor: Ceiling(6.89 * (1 + 10/100)) = Ceiling(6.89 * 1.1) = Ceiling(7.579) = 8 rolls
Based on these inputs, you would need to purchase 8 rolls of wallpaper.
Important Considerations
- Doors and Windows: While the calculator doesn't deduct for these, you will cut around them. The waste factor helps cover this. For very large openings, you might slightly reduce the waste factor, but it's safer to err on the side of caution.
- Sloped Ceilings or Irregular Walls: For non-standard rooms, consider consulting a professional or adding a higher waste factor.
- Dye Lots: Always buy all your wallpaper from the same dye lot to ensure consistent color. If you need extra later, it might be from a different lot and show a slight color variation.
- Professional Advice: If you're unsure, especially for expensive or complex patterns, it's always best to get a professional installer to measure and advise on quantities.
Use this calculator as a helpful guide to plan your wallpaper project with confidence!