House Wrap Calculator — ft, rolls, cost
How to use this calculator
Type building perimeter and wall height, a single wall, or net ft² already taken off the plans. Gables get added on top, doors and windows come out, then the calc adds shingle-lap overlap and a waste %. Pick a preset to load a real house footprint.
Seam tape — 2–3″ tape for all horizontal and vertical seams, ~165 ft per roll.
Fasteners — cap nails or cap staples, ~1 per ft² of wrap, 1000 per box.
Cost — per roll of wrap, tape, and fastener box.
Saved Calculations
| Time | Method | Net ft² | Rolls | Cost |
|---|
How to Calculate House Wrap
House wrap (a weather-resistive barrier, WRB) is installed over exterior sheathing before cladding to shed bulk water and reduce air infiltration. Take the building perimeter × wall height for gross wall area, add triangular gable areas (½ × base × peak height), then deduct doors (~20 ft² each) and windows (~15 ft² each). The overlap factor adds material consumed by the shingle-lapped horizontal and vertical seams, and the waste allowance covers cuts at corners, around flashed openings and torn courses.
Formulas
Gross area = perimeter × height + gable areas. Net area = gross − openings. Overlap factor = roll area ÷ [(roll width − horiz. overlap) × (roll length − vert. overlap)]. Adjusted area = net × overlap factor × (1 + waste%). Rolls = ⌈adjusted area ÷ roll coverage⌉. Seam tape length ≈ horizontal seams + vertical butt joints; fasteners ≈ 1 cap nail or cap staple per ft².
Roll Sizes
Common sizes: 3′×100′ (300 ft²), 5′×100′ (500 ft²), 9′×100′ (900 ft²), 9′×150′ (1,350 ft²), 10′×100′ (1,000 ft²). For standard 8′ walls, a 9′ or 10′ wide roll wraps the full story height in one course with overlap top and bottom; narrower 3′ rolls run multiple horizontal courses with a 6″ shingle lap. Pair this with the wall insulation calculator and vapor barrier calculator to complete the wall assembly.
FAQ
How much overlap? Minimum 6″ horizontal (shingle-lap so upper course laps over lower), 6–12″ at vertical butt seams per manufacturer specs; double the lap over inside corners. How many fasteners? Roughly 1 cap nail or cap staple per ft² of wrap, spaced 12–18″ along studs and 6″ at seams. Do I need seam tape? Yes — tape all horizontal and vertical seams, tears and penetrations with manufacturer-approved tape for a continuous air and water barrier. For roof and attic assemblies use the roof insulation calculator; for an air-seal upgrade compare spray foam.
On install day
Three things that blow the takeoff. Inside corners — IRC R703.2 and most manufacturers want the wrap to lap continuously around inside corners by a full 12″; if you cut at the corner you create a vertical seam that has to be taped and counter-flashed. Window flashing sequencing — the wrap goes over the sill flashing and behind the jamb/head flashing (reverse-shingle), not the other way around; getting it backwards is the #1 callback on a WRB job. UV exposure — Tyvek, Typar and most spunbonded wraps are warranted for ~120 days of exposure; if cladding is delayed past that, expect chalking and demand a re-wrap. Budget $0.35–0.75/ft² installed for the wrap itself in 2025 USA (material $0.10–0.20/ft², the rest is labor + tape + caps); a single-story 1,500 ft² ranch typically runs $400–900 in wrap and accessories. Pair this with a finish takeoff and the wall insulation calculator to close out the envelope.
Calculation notesWhat this calculator doesOpen the formula basis, references and assumptions when you need to verify the detailed method.Review details
Net enclosure area is adjusted for laps and waste, then divided by roll coverage and rounded up to whole rolls.
Reference context
- • IECC/IRC energy provisions
- • manufacturer coverage data
- • project climate-zone requirements
Important assumptions
- • Dimensions, quantities and prices entered by the user are correct.
- • Waste, laps, overlaps, compaction and delivery allowances must match the actual project.
- • Results are preliminary takeoff estimates, not a sealed structural design or permit approval.
Quality notes updated: August 1, 2026. The repository includes per-page checks for browser errors, populated results, metadata, US-market visibility, duplicate IDs and shared quality controls.
Reference names describe the applicable design and product context; they do not replace a project-specific code review. Local codes, drawings, specifications and manufacturer instructions govern the final work. Report a calculation or interface issue.
