Exterior planning guide

Exterior planning guide

Siding and insulation both start from net wall area. Openings, gables and product coverage have to stay on the page — a square is not a guess.

Measure walls, gables and openings

Use wall length and height, add gable triangles when they receive the same product, then deduct doors and windows. Insulation uses the cavity or coverage area of the selected batt or roll.

  • A siding square is 100 square feet of coverage after waste is applied.
  • Enter the selected product’s coverage, not a generic panel size, when the manufacturer differs.
  • Insulation package count uses the coverage printed on the selected batt or roll.

Siding and insulation are companion takeoffs

Open siding for exterior cladding squares. Open insulation for package counts of batts or rolls. Roofing is adjacent when the same elevation needs both wall cladding and roof covering, but the formulas stay separate.

Squares, packages and trim extras

Siding is typically ordered in squares plus starter, corners, J-channel and soffit as extras. Insulation is ordered in whole packages.

  • Keep waste visible for cuts around openings and gables.
  • House wrap, trim and fasteners are not included in a siding square count.
  • R-value and vapour control are product selections, not calculator outputs.

Planning boundary

These tools estimate coverage. They do not design weather barriers, attachment, wind rating or a thermal code path.