Roofing & Exterior

House Wrap Calculator: Wall Area, Rolls & Overlap

Estimate weather-resistive wrap purchase quantity from measured exterior wall area and the effective roll coverage you enter. Opening deductions and overlap reserve stay separate so the takeoff can be revised without changing the building geometry.

Maintained by Home Measure Lab Editorial TeamUpdated August 29, 2026Method & corrections

Project measurements

Change the defaults to match your project and the product you plan to buy.

Exterior wall perimeter

Average wrap height

Large doors/windows deducted

sq ft

Overlap / detail allowance

Quick values

Effective coverage per roll

sq ft

Price per roll (optional)

Project result

House-wrap plan

See gross wall area, large-opening deductions, overlap-adjusted target, whole rolls and purchased coverage.

Planning estimate only. Verify product coverage, package size, supplier specifications and project requirements before purchasing.

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Budget scenario

Add your current local costs

Use a current supplier subtotal or reuse a priced calculator result, then add optional delivery, tax and contingency. Home Measure Lab does not fetch or guess live prices.

Currency

Supplier / material subtotal

local

Delivery / project fees

optional

Tax

Contingency

This calculator does not currently expose a priced result. Enter a current supplier subtotal manually.

Material subtotal$0.00

Delivery / fees$0.00

Tax$0.00

Contingency$0.00

Planning total$0.00

Enter a current supplier subtotal or reuse a priced calculator result.

Budget values are local planning inputs, not live quotes. Verify tax treatment, delivery, labor and supplier pricing before purchasing.

Choose the right tool

When to use this calculator

You need weather-resistive wrap rolls from exterior wall field geometry and effective roll coverage.

Use a different calculator when

Use Siding for finish cladding packages or Wall Area for simple wall-surface measurement without wrap package conversion.

Siding Calculator →Wall Area Calculator →Soffit Calculator →

Methodology

Formula & assumptions

Gross wall area

exterior perimeter × average wrap height

Split stories or wall zones when heights differ materially.

Net wall area

gross wall area − large opening deductions

Small openings can be left in the field when cutting around them consumes material anyway.

Planning target

net area × (1 + entered overlap/detail allowance)

Keep laps, corners and repair reserve separate from measured geometry.

Roll quantity

planning target ÷ effective roll coverage, rounded up

Use the effective coverage of the selected roll/product.

How to measure this project

Measure exterior wall perimeter at a consistent wall line and record the height of each story or major wall zone. For gable ends, stepped walls and additions, use separate areas when a single perimeter-times-height rectangle would omit important geometry. Deduct large doors and windows only when that makes the takeoff more realistic; many small openings still consume wrap because the sheet must span and be cut around them. Keep the wall sketch so openings and extra zones remain traceable.

Before you buy materials

House-wrap product choice, drainage plane design, flashing integration, fasteners and installation sequence depend on the wall assembly and project requirements. Enter an effective roll coverage that reflects the selected product, required overlaps and practical cuts. Do not assume the nominal roll area is all usable. Corners, transitions, repairs and complex openings can increase material use, so keep a visible reserve rather than inflating the measured wall area.

Reference

House-wrap planning reference

Input	Quantity role	Verify
Perimeter × height	gross wall area	Split unlike wall zones.
Openings	large deductions	Do not over-deduct small cutouts.
Overlap/detail allowance	planning reserve	Use project/product conditions.
Roll coverage	package conversion	Use effective, not assumed, coverage.

Questions

Frequently asked questions

Should every window be subtracted from house-wrap area?

Not necessarily. Small openings often still consume field material because the wrap spans them before cutting; use deductions only when they improve the takeoff.

Is nominal roll area the same as effective coverage?

Not always. Overlaps and cuts reduce usable field coverage, so enter an effective value suitable for the selected product and project.

Does this include flashing tape?

No. Flashing and opening-detail materials are separate system components and are not inferred by this roll calculation.

Next step

Keep this project moving

Follow the measurement into the most useful related reference, calculator or project view.

Understand the inputHouse Wrap Wall Area Measurement GuideContinue →Compare a nearby toolSiding CalculatorContinue →Browse this project typeRoofing & Exterior calculatorsContinue →

Planning guides

Understand the inputs behind this calculator

All guides →

Roofing & Exterior

House Wrap Wall Area Measurement Guide

Measure exterior wall zones, large openings and gable areas before adding overlap reserve or converting the takeoff to whole rolls.

Read guide →

Roofing & Exterior

House Wrap Overlap and Roll Coverage Guide

Plan effective house-wrap roll coverage by separating nominal roll area from overlaps, corners, cuts and project-specific detail reserve.

Read guide →

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