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ATTIC CONVERSION

Attic Conversion Cost Calculator

Estimate the cost of converting an attic by area, scope, structure and bathroom.

JOB INPUTS

Enter your numbers

Loading saved values

Livable area in sq ft

sq ft
Livable area in sq ft

Basic, full or turnkey

Basic, full or turnkey

Roof structure work

Roof structure work

Add a bathroom

Add a bathroom
Results update automatically
CALCULATED RESULTUSD
Estimated total cost$48,000.00
Conversion$48,000.00
Structure change$0.00
Bathroom$0.00
FORMULA USED400 sq ft × $120.00 + structure + bathroom = $48,000.00

HOW TO USE IT

How to use the Attic Conversion Cost Calculator

  1. 1

    Enter the livable area in sq ft.

  2. 2

    Choose the scope (basic, full or turnkey).

  3. 3

    Set whether the structure changes and if a bathroom is added.

  4. 4

    Review the total cost and line-item breakdown.

THE MATH

Attic conversion cost formula

Total = area × rate + structure + bathroom

A full conversion runs about $120/sq ft. A structure change adds ~$30/sq ft and a bathroom ~$12,000.

PRACTICAL EXAMPLE

400 sq ft, full conversion, no structure change or bathroom

Conversion = 400 × $120 = $48,000. Total ≈ $48,000.

FAQ

Frequently asked questions

How much does an attic conversion cost in 2026?

Nationally, $30-$200/sq ft depending on scope and structure.

Basic, full or turnkey?

Full includes finishes and systems; turnkey handles everything including structure.

Do I need a permit?

Attic conversions usually require a permit depending on size and municipality.