CALC-D-001 · DRAWING NO. SD-001 · REV A
Siding calculator.
Drafted to scale · cited sources · honest numbers
Enter the wall dimensions, gable ends, and openings. The calculator returns vinyl squares, Hardie planks, or wood lap square footage with a material-cost range. Deducts doors, windows, and garage doors from gross wall area.
◈ DRAFTING PANEL · SIDING TAKEOFF · N.T.S.
SHEET SD-001 · REV A
Redline · scope notice Material takeoff only. Does not size J-channels, starter strips, corner posts, undersill trim, or frieze boards. Does not evaluate wind-zone fastener schedules (ASCE 7). Assumes rectangular walls; dormers and bay windows need separate takeoffs.
Note 01 · Field Procedure
How to measure the exterior
- Walk the perimeter and record total wall length in feet. Include all sides the siding will cover. Round up to the nearest foot.
- Measure wall height from the top of the foundation to the soffit line. For two-story homes, measure each story separately if the siding break is at a band board.
- Count gable ends. Measure each gable triangle: base width (eave to eave) and peak height (eave line to ridge). The calculator uses the triangle formula (0.5 x base x height).
- Count doors (standard 3x7 ft = 21 sqft each), windows (standard 3x4 ft = 12 sqft each), and garage doors (standard 16x7 ft = 112 sqft each). The calculator deducts these from gross wall area.
Note 02 · Equation
The formula
net = ( H × P + gables ) − openings
Hwall height in feet
Ptotal wall perimeter in feet
gablessum of gable triangle areas (0.5 × base × peak)
openingsdoors (21 sf) + windows (12 sf) + garage doors (112 sf)
Vinyl: order in squares (100 sqft). Hardie: order in 12 ft planks (8.25 in. width, 7 in. reveal after 1.25 in. overlap = 7 sqft each). Wood lap: order by sqft.
Note 03 · Sanity Ranges
Siding by house size
| T | Use case | Notes |
|---|---|---|
| ~800 sf | Small cottage / garage | Vinyl: ~10 squares. One-day job for two installers. |
| ~1,300 sf | Ranch / single-story | Vinyl: ~15 squares. Hardie: ~205 planks. Most common residential job. |
| ~2,000 sf | Two-story colonial | Vinyl: ~22 squares. Budget for scaffold rental. |
| ~3,000+ sf | Large home | Vinyl: ~33+ squares. Complex trim and multiple gables add 15% waste. |
Note 04 · References
Sources
Authorities cited on this sheet
- Polymeric Exterior Products Association (PEPA, formerly Vinyl Siding Institute) · Industry trade association for vinyl siding. Defines the 'square' (100 sqft) as the standard ordering unit. Installation manuals cover thermal expansion float-nail requirements.
- James Hardie HardiePlank Lap Siding · Product page for HardiePlank fiber cement lap siding. 12 ft planks, 8.25 in. width, 7 in. reveal after 1.25 in. blind-nail overlap (7 sqft coverage per plank). ASTM E136 noncombustible rating. Basis for the plank count on the spec slip.
- James Hardie Pro Resources · Installation instructions, ICC-ES evaluation reports, and best-practice guides for HardiePlank and Hardie trim systems.
- IRC 2021 Chapter 7 Wall Covering (R703) · IRC R703 governs exterior wall covering, including minimum lap on wood siding and clearance from grade. Basis for the wood lap 6 in. exposure assumption (nominal 8 in. board with 1 in. minimum lap).
PROJ MATERIALFOREMAN
SHT SD-001 / 014
REV A · 2026-04-19
DRAWN MF