Weatherstripping Length and Cost Calculator
Calculate the total length of weatherstripping needed for your doors and windows, along with the estimated material cost.
Formulas Used
Door perimeter (3-sided seal):
Door Length = 2 × Door Height + Door Width (inches) ÷ 12 = feet
Note: Only two vertical sides and the top are sealed with weatherstripping. The bottom of the door uses a separate door sweep.
Window perimeter (4-sided seal):
Window Length = 2 × (Window Width + Window Height) (inches) ÷ 12 = feet
Raw Total Length:
Raw Total = (Door Length × Number of Doors) + (Window Length × Number of Windows)
Adjusted Total Length:
Adjusted Total = Raw Total × (1 + Waste % ÷ 100)
Rolls Needed:
Rolls = ⌈ Adjusted Total ÷ Roll Length ⌉ (ceiling function)
Material Cost:
Cost = Adjusted Total (ft) × Price per Linear Foot
Assumptions & References
- Door weatherstripping covers three sides only (two vertical jambs + top header). The door bottom requires a separate door sweep product.
- Window weatherstripping covers all four sides of the window frame.
- All doors are assumed to be the same size; all windows are assumed to be the same size. For mixed sizes, calculate each group separately and sum the results.
- A waste/overlap factor of 10% is recommended as a default to account for corners, cuts, and overlaps.
- Typical foam tape weatherstripping costs $0.30–$1.00 per linear foot depending on material (foam, rubber, silicone, V-strip, door sweep).
- Standard interior door: 36 in × 80 in. Standard exterior door: 36 in × 80 in.
- Common roll lengths: 10 ft, 17 ft, 20 ft, 30 ft — check your product packaging.
- Reference: U.S. Department of Energy — Weatherstripping (energy.gov/energysaver/weatherstripping).
- Reference: This Old House — How to Weatherstrip a Door.