Weatherstripping Calculator
Calculate total linear feet of weatherstripping for all doors and windows.
Returns lengths with recommendations for foam tape, V-strip, and door sweeps.
Weatherstripping seals gaps around doors and windows to prevent air infiltration, moisture intrusion, and heat loss. Properly installed weatherstripping can reduce heating and cooling costs by 10–20% according to the U.S. Department of Energy.
Total length formula: Door Weatherstripping = 2 × Door Height + Door Width (top + two sides; threshold strip covers the bottom separately) Window Weatherstripping = 2 × (Window Height + Window Width) (full perimeter)
Gap size guide: Standard door gaps:
- Side gaps: 1/16" to 1/8" — use foam tape, V-strip, or door seal
- Top gap: 1/8" — use foam or brush seal
- Bottom gap: up to 3/4" — use door sweep or automatic drop seal
Material quantities: For a standard 36" × 80" door:
- Two sides: 2 × 80" = 160"
- Top: 36"
- Total = 196 inches = 16.3 linear feet (buy 18 ft to allow for overlap and cuts)
Cost estimate formula: Total Cost = Linear Feet × Price per Foot + Hardware Cost
Weatherstripping types and typical prices:
| Type | Price/ft | Best For | Lifespan |
|---|---|---|---|
| Foam tape | $0.10–0.25 | Light gaps, windows | 1–3 years |
| V-strip (tension seal) | $0.30–0.60 | Door sides, sliding windows | 5–10 years |
| Door sweep (brush) | $1–3/ft | Door bottoms | 3–5 years |
| Door sweep (automatic) | $20–60 each | High-end doors | 10+ years |
| Silicone bulb seal | $0.50–1.20/ft | Irregular gaps | 5–7 years |
Worked example: Home with 3 exterior doors (36"×80") and 6 windows (36"×48"): Doors: 3 × 16.3 ft = 48.9 ft Windows: 6 × (2 × (3 + 4)) = 6 × 14 = 84 ft Total: ~133 linear feet At $0.45/ft V-strip + $15/door sweep: 133 × $0.45 + 3 × $15 = $60 + $45 = ~$105 total