function calculateWallpaper() {
var roomWidth = parseFloat(document.getElementById("roomWidth").value);
var roomLength = parseFloat(document.getElementById("roomLength").value);
var roomHeight = parseFloat(document.getElementById("roomHeight").value);
var doorWidth = parseFloat(document.getElementById("doorWidth").value);
var doorHeight = parseFloat(document.getElementById("doorHeight").value);
var windowWidth = parseFloat(document.getElementById("windowWidth").value);
var windowHeight = parseFloat(document.getElementById("windowHeight").value);
var wallpaperRollWidth = parseFloat(document.getElementById("wallpaperRollWidth").value);
var wallpaperRollLength = parseFloat(document.getElementById("wallpaperRollLength").value);
var patternRepeat = parseFloat(document.getElementById("patternRepeat").value);
var resultDiv = document.getElementById("result");
resultDiv.innerHTML = ""; // Clear previous results
// Validate inputs
if (isNaN(roomWidth) || roomWidth <= 0 ||
isNaN(roomLength) || roomLength <= 0 ||
isNaN(roomHeight) || roomHeight <= 0 ||
isNaN(doorWidth) || doorWidth < 0 ||
isNaN(doorHeight) || doorHeight <= 0 ||
isNaN(windowWidth) || windowWidth < 0 ||
isNaN(windowHeight) || windowHeight <= 0 ||
isNaN(wallpaperRollWidth) || wallpaperRollWidth <= 0 ||
isNaN(wallpaperRollLength) || wallpaperRollLength <= 0 ||
isNaN(patternRepeat) || patternRepeat 0) {
totalRollsNeeded = Math.ceil(numberOfStripsNeeded / stripsPerRoll);
} else {
// This scenario implies a roll is too short to even cut one strip
resultDiv.innerHTML = "The wallpaper roll length is too short to cut even one strip for the room height plus pattern repeat.";
return;
}
resultDiv.innerHTML =
"
Calculating the amount of wallpaper you need is crucial to avoid running out mid-project or buying too much. The process involves measuring your room, accounting for doors and windows, and understanding the specifications of your chosen wallpaper.
Key Steps in Wallpaper Calculation:
Measure Your Room: You'll need the width, length, and height of your room in meters. These measurements will help you determine the total surface area of the walls.
Measure Openings: Note the width and height of any doors and windows. These areas won't be wallpapered, so their surface area needs to be subtracted from the total wall area.
Understand Wallpaper Roll Specifications: Wallpaper comes in rolls with specific widths and lengths. You also need to consider the "pattern repeat," which is the vertical distance on the wallpaper after which the pattern begins to repeat. This is important for matching patterns between strips, which often leads to some wastage.
Calculate Total Wall Area: The formula is `2 * (Room Width * Room Height + Room Length * Room Height)`.
Calculate Area of Openings: For each opening, calculate `Width * Height` and sum them up.
Calculate Net Wall Area: Subtract the total area of openings from the total wall area.
Determine Strips Needed: For each roll, you'll cut vertical strips. The length of each strip should be the room's height plus the pattern repeat to allow for matching. You then calculate how many such strips can be cut from a single roll. Divide the room's perimeter by the wallpaper roll width to find out how many strips you need in total.
Calculate Total Rolls: Divide the total number of strips needed by the number of strips you can get from one roll, and round up to the nearest whole number.
Example Calculation:
Let's assume you have a room with the following dimensions:
Room Width: 4 meters
Room Length: 5 meters
Room Height: 2.5 meters
Door Width: 0.9 meters
Door Height: 2.1 meters
Window Width: 1.2 meters
Window Height: 1.5 meters
And your wallpaper has these specifications:
Wallpaper Roll Width: 0.53 meters
Wallpaper Roll Length: 10.05 meters
Pattern Repeat: 0.64 meters
Using the calculator above with these values, you would find: