Siding & Exterior Wall Square Estimator
Calculate siding squares (100 sq ft), vinyl cartons, house wrap rolls, starter strips, and material cost based on net wall area and window deductions.
Calculated Results
Frequently Asked Questions
What is a 'square' of siding in construction?
In the building and roofing trades, one 'square' equals exactly 100 square feet of surface area. For example, a home with 1,800 square feet of exterior wall area requires 18 squares plus waste allowance.
How much waste allowance should be factored in for siding?
A 10% waste factor is sufficient for simple, single-story ranch homes with flat walls. For two-story homes with multiple gable triangles, dormers, and architectural bump-outs, a 15% to 20% waste allowance is necessary to account for angled cuts.
What is the difference between vinyl and fiber cement (Hardie) siding?
Vinyl siding is lightweight, rot-proof, low-maintenance, and costs $3 to $7 per sq ft installed. Fiber cement (James Hardie) is non-combustible, mimics real wood grain, resists hail impacts, and costs $8 to $14 per sq ft installed but requires painting every 10-15 years.
Why must vinyl siding be nailed loosely?
Vinyl siding expands and contracts significantly with outdoor temperature swings (up to 1/2-inch over a 12-foot plank). Nails should be placed in the center of the pre-punched slots with a 1/32-inch gap between the nail head and vinyl so panels can slide freely without warping or buckling.