Siding Calculator
Calculate how much siding you need for your house in squares with waste factor and cost estimates.
How much siding do I need for my house?
Calculate total wall area: (Perimeter x Height) - window/door openings. Siding sold in "squares" (100 sq ft). Formula: Total sq ft / 100 = squares needed. Add 10-15% waste for cuts, mistakes, pattern matching. Example: 1,500 sq ft house walls - 200 sq ft openings = 1,300 sq ft / 100 = 13 squares + 15% = 15 squares. Measure each wall separately for accuracy, especially with gables and irregular shapes.
What are the different types of siding materials?
Common siding types: Vinyl ($3-8/sq ft, low maintenance, 20-40 year life), Fiber cement ($5-12/sq ft, durable, paintable, 50+ years), Wood ($6-12/sq ft, classic look, needs maintenance, 20-40 years), Engineered wood ($4-9/sq ft, affordable, 30 years), Brick/Stone ($8-25/sq ft, permanent, 100+ years), Metal/Aluminum ($3-11/sq ft, durable, modern). Consider climate, maintenance, HOA rules, and ROI when choosing.
How do I calculate siding for gables and peaks?
Gable area = (Width x Height) / 2 for triangular sections. Measure from eave to peak vertically, full width horizontally. Add to main wall area. Example: 20' wide gable, 8' peak height = (20 x 8) / 2 = 80 sq ft. For complex rooflines, break into triangles and rectangles. Always add extra waste (15-20%) for angled cuts. Dormers calculated separately: treat as mini-houses with their own gables.
What waste factor should I use for siding?
Waste factors by complexity: Simple rectangle house: 10%. Standard house with windows/doors: 12-15%. Complex architecture (many corners, angles): 15-20%. Diagonal/pattern installation: 20-25%. Board & batten style: 15%. Also consider: Defective pieces (5%), corner trim, starter strips, J-channels. Better to over-order by 1-2 squares than pay rush delivery. Keep extra for future repairs - colors/lots can vary.
How long does siding installation take?
Typical installation times: 1,500 sq ft house (vinyl): 1-2 weeks with crew of 2-3. Fiber cement: 2-3 weeks (heavier, more cutting). Wood siding: 2-4 weeks (precision fitting, painting). Includes prep, wrap, trim, cleanup. Delays from: Weather (rain/extreme temps), repairs (sheathing, windows), permit inspections. DIY takes 3-4x longer. Fall/Spring best seasons - avoid summer heat and winter cold for optimal installation conditions.
Do I need to remove old siding first?
Usually yes - removing old siding allows: Inspection/repair of sheathing and framing, proper house wrap installation, flat surface for new siding, building code compliance. Can side over existing if: Only one layer exists, surface is flat/sound, no moisture/rot issues, local codes allow, not too heavy (structural concern). Never install over 2+ layers. Removal cost: $1-3/sq ft. Reveals problems early - budget 10-20% extra for unexpected repairs discovered during removal.
What is a "square" of siding?
A square = 100 square feet of coverage. Industry standard measurement for siding, roofing. Example: 1,200 sq ft house = 12 squares base + waste. NOT 10x10 feet physical - refers to area covered. Packaging varies: Vinyl comes in boxes covering 1-2 squares, fiber cement in bundles of planks totaling 25-33 sq ft. When ordering, specify "squares" not pieces. Price quotes typically per square ($300-800/square installed depending on material).