10.3 Physical Deterioration (Curable and Incurable)

Key Takeaways

  • Physical deterioration is loss in value from wear and tear, age, deferred maintenance, and physical decay of improvements—not from layout flaws or neighborhood decline.
  • Curable physical deterioration exists when the cost to cure is equal to or less than the value added (or loss avoided) by curing; deferred maintenance is the classic curable category.
  • Incurable physical deterioration is loss that is not economically rational to cure as of the effective date; it is often measured with age-life concepts on short-lived and long-lived components.
  • Short-lived items (HVAC, roof cover, carpet, appliances) wear out faster than long-lived items (foundation, framing, structure); breakdown methods separate them.
  • Cost-to-cure ≤ value added is the economic test for curability; if cure costs more than it returns, the deterioration is treated as incurable even if physically fixable.
Last updated: August 2026

Physical Deterioration Inside Accrued Depreciation

Accrued depreciation is the total loss in value from cost new for any cause as of the effective date. Traditional breakdown groups causes into three buckets:

CauseCore ideaECO home
Physical deteriorationWear, age, decay, poor maintenanceV.c (this section)
Functional obsolescenceDesign, utility, or component inadequacy/superadequacy inside the propertyV.d
External obsolescenceLoss from outside the property (location/economic)V.e

Physical deterioration is the reduction in value of improvements due to physical wear and tear, the passage of time, exposure, and neglect. The roof wears out. Paint peels. The foundation settles. Framing ages. These are physical problems—even when the cure is a contractor invoice.

Physical deterioration is not:

  • A three-bedroom house in a four-bedroom market (functional)
  • A well-kept house next to a new landfill (external)
  • Land “wearing out” like a machine (land is valued separately; site improvements can deteriorate)

Curable vs Incurable — The Economic Test

ECO splits physical deterioration into curable and incurable. The split is economic, not merely whether a contractor can swing a hammer.

Curable physical deterioration

Curable when, as of the effective date, it is rational to cure because:

Cost to cure ≤ Value added by the cure
(or ≤ the loss in value avoided by curing—same idea)

Classic label for many curable physical items: deferred maintenance — repairs that a prudent buyer would expect to be fixed and that restore more value (or prevent more loss) than they cost.

Examples often treated as curable physical (when economically justified):

  • Broken windows, damaged gutters
  • Peeling paint, missing shingles on an otherwise sound roof cover near end of life may be more complex—follow the stem
  • Inoperative fixtures that are cheap to replace relative to contribution
  • Safety items buyers will deduct dollar-for-dollar if left undone

Incurable physical deterioration

Incurable when curing is not economically justified as of the effective date—even if physically possible. The structure has used up part of its life; you do not rebuild the entire frame every year just because wood is aging.

Examples:

  • Age-related loss in foundation and framing that will only be “cured” by major renovation disproportionate to value added
  • Remaining life loss on a 15-year-old roof that still functions, where full replacement now would not pay back yet
  • Physical wear distributed through long-lived components measured by age-life ratios
Curable physicalIncurable physical
Economic testCost to cure ≤ value addedCost to cure > value added (or cure not market-rational now)
Typical itemsDeferred maintenance, fix-it listAge-life loss on short- and long-lived components
MeasurementOften cost to cure (as the depreciation amount)Often age-life or residual after curable items
Buyer behaviorBuyer deducts repair cost if seller leaves itBuyer accepts aging as part of price vs new

Critical exam sentence: Something can be physically fixable but economically incurable. Curability follows the market math, not the toolbox.

Deferred Maintenance vs Short-Lived vs Long-Lived

Breakdown thinking (preview of ECO V.f methods) sorts physical issues into practical piles:

1. Deferred maintenance (usually curable physical)

Items in need of immediate repair; prudent buyer treats them as near-term cash outlays.

Depreciation amount for curable deferred maintenance is typically the cost to cure (sometimes adjusted if cure adds more or less than cost—exam usually equates curable physical depreciation to cost to cure when the test is met).

Example: Missing handrail and damaged entry door. Cost to cure = $1,200. Market will pay $1,200 more (or reduce offer $1,200) if fixed vs not. Curable physical deterioration = $1,200.

2. Short-lived items

Components with lives shorter than the building’s total economic life: roof cover, HVAC, water heater, carpet, appliances, exterior paint, etc.

Each short-lived item can have its own effective age / useful life ratio.

Depreciation (incurable physical on short-lived item)
(Effective age / Useful life) × Cost new of that item
(after treating any deferred replacement as curable if immediate replacement is required)

3. Long-lived items

Components expected to last about as long as the structure’s total economic life: foundation, framing, many structural elements, some underground utilities, etc.

Depreciation (incurable physical on long-lived)
(Effective age / Total economic life) × Cost new of long-lived components

CategoryLife relative to buildingTypical measurement
Deferred maintenanceDue nowCost to cure
Short-livedShorter component lifeAge-life on component cost
Long-lived≈ building economic lifeAge-life on long-lived cost

Worked Example 1 — Curability Test

Item: Exterior paint failure.
Cost to cure (repaint): $6,000
Value added if cured (from market/paired logic in stem): $6,500

Because $6,000 ≤ $6,500 → curable physical deterioration.
Depreciation charged for this item = $6,000 (cost to cure).

Alternate facts: Cost to cure = $6,000; value added = $3,500.
$6,000 > $3,500 → not economically curable as a “curable” line in the classic sense; treat under incurable physical / age-life logic rather than forcing a full cost-to-cure deduction as if a rational buyer would paint solely for a $3,500 bump. (Stems vary; apply the inequality given.)

Worked Example 2 — Short-Lived Roof

Roof cover cost new: $12,000
Useful life: 20 years
Effective age: 15 years
Condition: Still functioning; no immediate failure (not deferred maintenance)

Incurable physical on roof ≈ (15/20) × $12,000 = $9,000
Remaining contribution of roof ≈ $12,000 − $9,000 = $3,000

If instead the roof is failed and must be replaced immediately, many analyses treat full replacement cost as curable deferred maintenance ($12,000), and you do not also take 15/20 age-life on the same roof (avoid double counting).

Worked Example 3 — Long-Lived Structure

Long-lived components cost new: $280,000
Total economic life of building: 60 years
Effective age: 12 years

Incurable physical (long-lived) ≈ (12/60) × $280,000 = $56,000

Worked Example 4 — Combined Physical Deterioration

Cost new (replacement) of improvements: $400,000
Split for teaching:

Component groupCost new
Long-lived$300,000
Short-lived (aggregate for simplicity)$90,000
Items in deferred maintenance (subset of short-lived needing immediate cure)$10,000 cost to cure (and $10,000 of the short-lived cost new is tied to those failed items)

Simplifying assumptions for a clean exam-style total:

  1. Curable physical (deferred maintenance): cost to cure = $10,000
  2. Remaining short-lived cost new after removing failed items: $80,000; average effective age/useful life = 40% worn → incurable short-lived = 0.40 × $80,000 = $32,000
  3. Long-lived: effective age 10 / life 50 → 20% × $300,000 = $60,000

Total physical deterioration = $10,000 + $32,000 + $60,000 = $102,000

Depreciated cost before functional/external = $400,000 − $102,000 = $298,000 (then subtract FO and EO if any; add land).

Effective Age vs Chronological Age

TermMeaning
Chronological ageYears since built
Effective ageAge indicated by condition and utility; may be less than chronological if well maintained/updated, or more if abused
Remaining economic lifeYears of useful life expected from the effective date
Total economic lifeEffective age + remaining economic life (conceptually)

Physical deterioration depends on effective age and condition, not the birthday cake number alone. A 40-year-old home fully renovated may have a younger effective age; a 10-year-old neglected home may have an older effective age.

What Physical Deterioration Is Not (Trap Table)

ObservationCorrect depreciation type
Worn carpetPhysical (often short-lived)
Outdated floor planFunctional
Next to noisy highwayExternal
Broken HVACPhysical (curable if cost-to-cure test met)
Ceiling height too low for modern retailFunctional
Overbuilt marble foyer in a tract marketFunctional (superadequacy)

Mislabeling functional or external loss as “physical” is a common multiple-choice distractor.

Measurement Methods Preview (Ch. 11)

ECO V.f lists methods of estimating depreciation:

  1. Age-life and modified age-life — overall or modified ratios
  2. Breakdown — physical (curable/incurable, short/long-lived) + functional + external
  3. Market extraction — extract total depreciation from sales, then allocate if needed

This section’s job is to define physical curable/incurable and the cost-to-cure test so those methods have meaning. You will compute full age-life problems in Chapter 11; here, nail the concepts and simple arithmetic.

Process Checklist for Physical Items

  1. Identify the defect or wear as physical (not design or off-site).
  2. Ask: Is immediate cure market-rational? Cost to cure ≤ value added?
  3. If yes → curable; depreciation ≈ cost to cure (typically).
  4. If no → incurable; use age-life on short-lived and/or long-lived components.
  5. Do not double-count the same roof as both 100% deferred maintenance and 75% age-life.
  6. Sum physical deterioration before or within the full breakdown with functional and external.

Common Exam Traps

  • Calling any repairable item curable without the economic test.
  • Using chronological age when the stem gives effective age.
  • Applying age-life to land.
  • Treating deferred maintenance as incurable “because the owner has not fixed it yet.”
  • Double-counting short-lived items.
  • Confusing physical curable cost-to-cure with functional curable cost-to-cure (functional has its own deficiency/superadequacy math—next section).

Bridge

Physical deterioration answers: How worn is the physical plant? Functional and external obsolescence answer: Even if brand new physically, would the market still penalize this improvement for design or for the world outside the property line? Section 10.4 completes the depreciation cause triad under ECO V.d and V.e.

Test Your Knowledge

Deferred maintenance is best classified as which form of depreciation when the cost to cure is less than or equal to the value added by the cure?

A
B
C
D
Test Your Knowledge

A short-lived component has a cost new of $20,000, a useful life of 20 years, and an effective age of 5 years. It is functioning and does not require immediate replacement. The indicated incurable physical deterioration on this component by age-life is:

A
B
C
D