Siding Calculator

Exterior Cladding & Siding Takeoff Estimation

Siding protects building envelope sheathing from moisture intrusion and wind while providing curb appeal. In North American construction, siding is measured and quoted in Squares.

Primary Siding Estimation Formulas

• Rectangular Wall Area: Area_wall = Length (ft) × Height (ft)

• Triangular Gable Area: Area_gable = (1) / (2) × Base Width (ft) × Peak Height (ft)

• Net Siding Surface Area: Area_net = - Doors and Windows

• Total Siding Squares: Squares = Area_net ×100

• Vinyl Siding Cartons: Boxes = Squares2 (Standard 2 Squares per Box)

Average Installed Siding Costs Per Square

• Standard Vinyl Siding: 300 - 550 per square

• Engineered Wood (LP SmartSide): 550 - 800 per square

• Fiber Cement (James Hardie): 650 - 1,100 per square

• Natural Cedar Wood Siding: 900 - 1,500 per square

• Stone Veneer Accent Siding: 1,200 - 2,500 per square

How to Use This Calculator

Enter your Gross Wall Surface Area (Sq Ft) (e.g. 2000 in sq ft), Triangular Gable Ends Area (Sq Ft) (e.g. 250 in sq ft), Doors, Windows & Opening Deductions (Sq Ft) (e.g. 350 in sq ft), Siding Material & Profile — choose from Vinyl Siding (2 Squares/Box — ~350/sq installed), Fiber Cement / HardiePlank (~750/sq installed), Engineered Wood / LP SmartSide (~650/sq installed), Waste, Overlap & Offcut Allowance (%) (e.g. 10 in %), and Estimated Installed Cost Per Square () (e.g. 350 in /square). Measure twice before entering dimensions — small measurement errors scale up significantly in material estimates.

The Formula

Standard housewrap roll: 9' x 100' = 900 sq ft (810 sq ft net with 10% overlap)

Worked Example

A two-story home with 2,250 gross sq ft of exterior surface and 350 sq ft of window/door openings has 1,900 sq ft net siding area. Adding 10% for diagonal cuts on gables equals 20.9 squares (7,315 installed vinyl budget).

Understanding Your Result

Construction estimates are starting points — site conditions, material specifications, and local code requirements will affect final quantities and costs. Always obtain at least three contractor bids for major projects. Local building departments can confirm permit requirements and inspection milestones. Add waste factors appropriate to the material type and complexity: 10% for simple rectangular shapes, 15–20% for complex geometries or custom cuts.