Understanding Your Paint Needs: The Benjamin Moore Calculator Explained
Planning a painting project, whether it's a single room or your entire home, requires careful estimation of the materials needed. The Benjamin Moore Paint Calculator is a handy tool designed to help you determine precisely how much paint you'll need, minimizing waste and ensuring you have enough to complete the job beautifully. This calculator takes into account the dimensions of your space, the number and size of openings like windows and doors, the number of coats you plan to apply, and the specific coverage rate of the paint you choose.
How the Calculation Works
The core of the paint calculation involves determining the total paintable surface area and then dividing that by the paint's coverage rate. Here's a breakdown of the formula:
Calculate Wall Area: The total area of the walls is calculated by finding the perimeter of the room and multiplying it by the room's height.
Perimeter = 2 * (Room Length + Room Width)
Total Wall Area = Perimeter * Room Height
Calculate Area of Openings: The total area occupied by windows and doors is subtracted from the total wall area, as these areas will not be painted.
Total Window Area = Number of Windows * Area per Window
Total Door Area = Number of Doors * Area per Door
Total Opening Area = Total Window Area + Total Door Area
Calculate Paintable Surface Area: This is the actual area that needs to be covered with paint.
Paintable Surface Area = Total Wall Area – Total Opening Area
Calculate Total Paint Required: This accounts for multiple coats and the paint's coverage.
Total Paint Needed (in gallons) = (Paintable Surface Area * Number of Coats) / Coverage per Gallon
Our calculator simplifies this process by prompting you for the necessary measurements and performing these calculations automatically. It's important to note that Coverage per Gallon is often found on the paint can label and can vary between paint types and brands. Benjamin Moore typically states coverage around 350-400 sq ft per gallon, but always check your specific product.
When to Use This Calculator
Interior Painting Projects: Estimate paint for bedrooms, living rooms, kitchens, hallways, and other interior spaces.
Exterior Painting Projects: While this calculator is primarily for interior walls, a similar principle applies to exterior surfaces. You would adjust inputs for the specific dimensions and account for architectural features.
Budgeting: Accurately estimate paint costs for renovations or new builds.
Material Purchasing: Ensure you buy the right amount of paint to avoid multiple trips to the store or over-purchasing.
Tips for Accurate Measurement:
Measure walls in feet.
For windows and doors, measure the entire frame opening rather than just the glass.
If you have unusual ceiling heights or complex room shapes, you may need to adjust calculations or consult with a painting professional.
Always consider buying slightly more paint than calculated to account for touch-ups, potential spills, or intricate cutting-in work.
Using the Benjamin Moore Paint Calculator is a smart step towards a successful and efficient painting project. By understanding the basic principles and providing accurate inputs, you can confidently purchase the right amount of high-quality Benjamin Moore paint for your needs.
function calculatePaint() {
var roomLength = parseFloat(document.getElementById("roomLength").value);
var roomWidth = parseFloat(document.getElementById("roomWidth").value);
var roomHeight = parseFloat(document.getElementById("roomHeight").value);
var numWindows = parseInt(document.getElementById("numWindows").value) || 0;
var windowAreaPerWindow = parseFloat(document.getElementById("windowAreaPerWindow").value) || 15;
var numDoors = parseInt(document.getElementById("numDoors").value) || 0;
var doorAreaPerDoor = parseFloat(document.getElementById("doorAreaPerDoor").value) || 20;
var coatsOfPaint = parseInt(document.getElementById("coatsOfPaint").value) || 2;
var coveragePerGallon = parseFloat(document.getElementById("coveragePerGallon").value) || 350;
var resultDisplay = document.getElementById("result-value");
// Input validation
if (isNaN(roomLength) || isNaN(roomWidth) || isNaN(roomHeight) || roomLength <= 0 || roomWidth <= 0 || roomHeight <= 0) {
resultDisplay.innerHTML = "Please enter valid room dimensions.";
return;
}
if (isNaN(coatsOfPaint) || coatsOfPaint <= 0) {
resultDisplay.innerHTML = "Please enter a valid number of coats.";
return;
}
if (isNaN(coveragePerGallon) || coveragePerGallon <= 0) {
resultDisplay.innerHTML = "Please enter a valid paint coverage rate.";
return;
}
if (isNaN(numWindows) || numWindows < 0) {
resultDisplay.innerHTML = "Please enter a valid number of windows.";
return;
}
if (isNaN(windowAreaPerWindow) || windowAreaPerWindow < 0) {
resultDisplay.innerHTML = "Please enter a valid window area.";
return;
}
if (isNaN(numDoors) || numDoors < 0) {
resultDisplay.innerHTML = "Please enter a valid number of doors.";
return;
}
if (isNaN(doorAreaPerDoor) || doorAreaPerDoor < 0) {
resultDisplay.innerHTML = "Please enter a valid door area.";
return;
}
// Calculations
var perimeter = 2 * (roomLength + roomWidth);
var totalWallArea = perimeter * roomHeight;
var totalWindowArea = numWindows * windowAreaPerWindow;
var totalDoorArea = numDoors * doorAreaPerDoor;
var totalOpeningArea = totalWindowArea + totalDoorArea;
var paintableSurfaceArea = totalWallArea – totalOpeningArea;
// Ensure paintable surface area is not negative
if (paintableSurfaceArea < 0) {
paintableSurfaceArea = 0;
}
var totalGallonsNeeded = (paintableSurfaceArea * coatsOfPaint) / coveragePerGallon;
// Display the result, rounded up to the nearest whole gallon
resultDisplay.innerHTML = Math.ceil(totalGallonsNeeded).toFixed(0) + " Gallons";
}