Cost Approach Valuation Calculator

The cost approach is one of three standard real estate appraisal methods (alongside the sales comparison and income approaches): it estimates value by asking what it would cost to replace the improvements new today, then subtracting the value already lost to depreciation, and adding the land value back in separately -- Property Value = Land Value + (Replacement Cost New - Total Depreciation). Replacement Cost New is simply Building Area times Replacement Cost/Sq Ft. This calculator subtracts three kinds of loss from that figure: physical depreciation, calculated using the straight-line "age-life" method (Building Age divided by Economic Life, capped at 100%, so a building at or past the end of its economic life is treated as fully physically depreciated); Functional Obsolescence, a percentage loss for outdated design or features; and External Obsolescence, a percentage loss from factors outside the property itself, like a declining neighborhood or nearby land use.

Building Value is Replacement Cost New minus all three, floored at zero so it never goes negative even if the combined depreciation and obsolescence percentages are large. Land-to-Value Ratio shows what share of the total appraised value is attributable to the land rather than the improvements, which appraisers watch because a very high land-to-value ratio can signal that a property's improvements are functionally or economically obsolete relative to the site's value. The cost approach tends to be most reliable for new or recently built construction (where depreciation is minimal and easy to estimate) and for special-use properties that rarely sell (schools, churches, government buildings) where comparable sales data is scarce; it becomes less reliable for older buildings, where depreciation and obsolescence are harder to measure precisely, which is why appraisers typically cross-check it against the sales comparison and income approaches rather than relying on it alone.