Board on board fencing, also known as shadowbox fencing, is a popular style that offers privacy while allowing for some air circulation. It features pickets that are attached to rails on alternating sides, creating an overlap effect. This design enhances privacy compared to standard privacy fences because the overlap prevents direct lines of sight through gaps.
Calculating the cost of a board on board fence involves several key components: the cost of the wood for the pickets, the cost of posts, and the labor involved.
Cost Breakdown:
1. Picket Material Cost:
This is often the largest component of the cost. To calculate this, we need to determine the total linear footage of boards required.
Effective Board Width: For board on board, each board effectively covers its own width plus a portion of the overlap. The actual coverage of a single board against the fence line is (Board Width - Board Overlap) inches.
Total Board Coverage Needed: This is simply the Total Fence Length in feet.
Number of Boards Across the Fence: To cover the entire fence length, you'll need Total Fence Length (feet) * 12 inches/foot / (Board Width (inches) - Board Overlap (inches)) boards.
Linear Feet of Boards: Since we're estimating based on boardWidth, we can simplify. For every foot of fence length, we need to account for the height and overlap. A common approach is to consider the number of boards needed per foot. The number of boards per linear foot of fence is calculated as: 12 inches/foot / (Board Width - Board Overlap) inches/board. This gives you boards per foot. Then, multiply by the total fence length. A more direct calculation for total linear feet of boards:
Total Fence Length (ft) * (Fence Height (ft) * 12 inches/ft) / (Board Width (inches) - Board Overlap (inches)). This gives you the total linear inches of board needed, which you then divide by 12 to get linear feet.
Total Picket Cost:(Total Linear Feet of Boards) * (Cost per Linear Foot of Board).
2. Post Cost:
Fence posts provide the structural support for the fence.
Number of Posts: You need a post at the beginning and end of the fence, and then posts spaced evenly. The number of posts is approximately (Total Fence Length / Post Spacing) + 1. We round up to ensure coverage.
Total Post Cost:(Number of Posts) * (Cost per Fence Post).
3. Labor Cost:
This covers the installation of pickets, posts, and rails.
Total Labor Cost:Total Fence Length (feet) * Labor Cost per Linear Foot.
Total Estimated Cost:
The sum of Picket Material Cost, Post Cost, and Labor Cost.
Example Calculation:
Let's calculate the cost for a 100-foot long, 6-foot high board on board fence with 6-inch wide boards that overlap by 1 inch. Posts are spaced 8 feet apart, cost $25 each. Board material costs $2.50 per linear foot, and labor is estimated at $15 per linear foot.
Number of boards needed per linear foot of fence: 12 inches / 5 inches/board = 2.4 boards/foot.
Total linear feet of boards needed: 100 feet * 2.4 boards/foot * (6 feet height / (12 inches/foot)) — Wait, this calculation is confusing. Let's use total surface area approach.
Total linear inches of board = (Total Fence Length in feet * 12 in/ft) * (Fence Height in feet * 12 in/ft) / ((Board Width in inches – Board Overlap in inches) * Fence Height in feet)
Let's use a more common industry approach:
Total surface area of fence = 100 ft * 6 ft = 600 sq ft.
Each board is 6 inches (0.5 ft) wide.
Effective coverage per board = (6 inches – 1 inch) / 12 inches/ft = 5/12 ft.
Number of boards needed to cover the length = 100 ft / (5/12 ft/board) = 240 boards.
Total linear feet of board = 240 boards * (6 ft height / (12 inches/ft)) –> Still not right.
Let's re-approach board calculation:
For every 1 foot of fence length:
We need to cover 6 feet of height.
Each board is 6 inches wide.
Boards overlap by 1 inch. So, each board effectively covers 5 inches of width along the fence line.
Number of boards needed to cover 1 foot (12 inches) of fence line = 12 inches / 5 inches/board = 2.4 boards.
So, for 100 feet of fence line, we need 100 ft * 2.4 boards/ft = 240 boards.
Each board is 6 feet tall.
Total linear feet of boards needed = 240 boards * 6 feet/board = 1440 linear feet.
Picket Material Cost: 1440 linear feet * $2.50/linear foot = $3600.00
Post Cost Calculation:
Number of Posts: (100 feet / 8 feet/post) + 1 = 12.5 + 1 = 13.5. Rounded up to 14 posts.
Total Post Cost: 14 posts * $25/post = $350.00
Labor Cost Calculation:
Total Labor Cost: 100 feet * $15/linear foot = $1500.00
function calculateFenceCost() {
var fenceLength = parseFloat(document.getElementById("fenceLength").value);
var fenceHeight = parseFloat(document.getElementById("fenceHeight").value);
var boardWidth = parseFloat(document.getElementById("boardWidth").value);
var boardOverlap = parseFloat(document.getElementById("boardOverlap").value);
var boardCostPerLinearFoot = parseFloat(document.getElementById("boardCostPerLinearFoot").value);
var postSpacing = parseFloat(document.getElementById("postSpacing").value);
var postCost = parseFloat(document.getElementById("postCost").value);
var laborCostPerLinearFoot = parseFloat(document.getElementById("laborCostPerLinearFoot").value);
var details = "";
var totalFenceCost = 0;
// — Input Validation —
if (isNaN(fenceLength) || fenceLength <= 0) {
alert("Please enter a valid Fence Length.");
return;
}
if (isNaN(fenceHeight) || fenceHeight <= 0) {
alert("Please enter a valid Fence Height.");
return;
}
if (isNaN(boardWidth) || boardWidth <= 0) {
alert("Please enter a valid Board Width.");
return;
}
if (isNaN(boardOverlap) || boardOverlap < 0) {
alert("Please enter a valid Board Overlap (cannot be negative).");
return;
}
if (boardWidth <= boardOverlap) {
alert("Board Width must be greater than Board Overlap.");
return;
}
if (isNaN(boardCostPerLinearFoot) || boardCostPerLinearFoot < 0) {
alert("Please enter a valid Cost per Linear Foot of Board.");
return;
}
if (isNaN(postSpacing) || postSpacing <= 0) {
alert("Please enter a valid Post Spacing.");
return;
}
if (isNaN(postCost) || postCost < 0) {
alert("Please enter a valid Cost per Fence Post.");
return;
}
if (isNaN(laborCostPerLinearFoot) || laborCostPerLinearFoot < 0) {
alert("Please enter a valid Estimated Labor Cost per Linear Foot.");
return;
}
// — Calculations —
// 1. Picket Material Cost
var effectiveBoardCoverageInches = boardWidth – boardOverlap; // inches per board coverage
var boardsPerLinearFootOfFence = 12 / effectiveBoardCoverageInches; // boards needed to cover 12 inches of fence line
var totalBoardsNeeded = fenceLength * boardsPerLinearFootOfFence;
var totalLinearFeetOfBoards = totalBoardsNeeded * (fenceHeight * 12 / 12); // Assuming boards are sold in standard heights, here we use fenceHeight directly. If boards come in specific lengths like 8ft, this would need adjustment. For simplicity, we use fenceHeight.
var picketMaterialCost = totalLinearFeetOfBoards * boardCostPerLinearFoot;
details += "Picket Material:";
details += "Effective Board Coverage: " + effectiveBoardCoverageInches.toFixed(2) + " inches";
details += "Boards per Linear Foot of Fence: " + boardsPerLinearFootOfFence.toFixed(2) + "";
details += "Total Boards Needed: " + totalBoardsNeeded.toFixed(0) + "";
details += "Total Linear Feet of Boards: " + totalLinearFeetOfBoards.toFixed(2) + " ft";
details += "Cost: " + picketMaterialCost.toFixed(2) + "";
// 2. Post Cost
var numberOfPosts = Math.ceil(fenceLength / postSpacing) + 1;
var totalPostCost = numberOfPosts * postCost;
details += "Posts:";
details += "Number of Posts: " + numberOfPosts + "";
details += "Cost: " + totalPostCost.toFixed(2) + "";
// 3. Labor Cost
var totalLaborCost = fenceLength * laborCostPerLinearFoot;
details += "Labor:";
details += "Cost: " + totalLaborCost.toFixed(2) + "";
// 4. Total Cost
totalFenceCost = picketMaterialCost + totalPostCost + totalLaborCost;
document.getElementById("result-value").innerText = "$" + totalFenceCost.toFixed(2);
document.getElementById("result-details").innerHTML = details;
}