Calculate renovation ROI

Rank proposed improvements by expected property value added relative to quoted cost.

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ToolRenovation ROI Calculator
Input
Output
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How it works

Each line contains one name, cost, and estimated added value, and its return divides value minus cost by cost. Portfolio return uses combined value minus combined cost divided by combined cost, avoiding the distortion of averaging unlike project percentages.

Formula
improvement ROI = (added value − cost) ÷ cost × 100
  • No cost or uplift defaults are supplied because quotes and local valuations must support them.
  • Break-even count includes an improvement whose added value exactly equals its cost.

Worked example

Three possible improvements
Each line is name, cost, expected added value
Input
											Kitchen refit, 12000, 18000,New boiler, 3000, 2000,Loft insulation, 800, 1500
Output
												Total cost: 15800
Total added value: 21500
Total net return: 5700
Overall ROI percent: 36.08
Best improvement name: Loft insulation
Best improvement ROI percent: 87.5
Worst improvement name: New boiler
Worst improvement ROI percent: -33.33
Improvements count: 3
Improvements above break even count: 2

When to use this

Pre-sale home improvements, investor refurbishment scopes, and survey follow-ups compare contractor quotes with evidence-backed expected value uplift.

Edge cases

  • An improvement name containing a comma creates more than three columns and is rejected rather than ambiguously parsed.
  • A zero or negative cost is rejected because ROI has no valid cost denominator.
  • Added value below cost produces a negative return and remains eligible to be named the worst option.