Mass appraisal models assume average condition for every property in a neighborhood. If your property has condition issues that reduce its value below the neighborhood average, you have a strong basis for appeal — and the evidence is often sitting right in front of you.
What Counts as Condition Evidence?
Condition evidence is any physical characteristic of your property that makes it worth less than a comparable property in average condition. This includes deferred maintenance (roof, HVAC, plumbing), structural issues (foundation, framing), functional obsolescence (outdated floor plan, low ceilings), and external factors (location, flood zone, noise).
Physical Condition Issues
| Issue | Typical Value Impact | Documentation Needed |
|---|---|---|
| Roof replacement needed | −$8,000–$20,000 | Roofing contractor estimate |
| HVAC replacement needed | −$5,000–$15,000 | HVAC contractor estimate |
| Foundation issues | −$10,000–$50,000+ | Structural engineer report |
| Deferred maintenance (general) | −5–15% of value | Photos + contractor estimates |
| Outdated kitchen/baths | −$5,000–$20,000 | Photos, renovation estimates |
| Water damage/mold | −$10,000–$50,000+ | Remediation estimate, photos |
How to Document Physical Condition
Photograph every condition issue with date-stamped photos. Get written estimates from licensed contractors for any needed repairs. The estimate does not need to be a full contract — a written scope and price from a licensed contractor is sufficient.
Take photos on the day of your hearing if possible, or within the past 30 days. The more recent the documentation, the more credible it is.
Location and External Factors
External factors that reduce value are often overlooked but can be very significant. These include: proximity to a busy road or highway (traffic noise, safety concerns), proximity to railroad tracks, location under high-voltage power lines, flood zone designation (FEMA Zone AE or AO), proximity to industrial facilities, and backing to a commercial property.
| External Factor | Typical Value Impact | Documentation |
|---|---|---|
| Busy road (>20,000 ADT) | −5–15% | Traffic count data, noise measurements |
| Flood Zone AE/AO | −5–20% | FEMA flood map, flood insurance cost |
| High-voltage power lines | −5–10% | Utility easement map, proximity measurement |
| Railroad tracks (within 500 ft) | −5–10% | Map showing distance |
| Industrial neighbor | −5–15% | Photos, odor/noise documentation |
Functional Obsolescence
Functional obsolescence is a loss in value due to features that are outdated or inadequate compared to current market standards. Examples include: low ceiling heights (under 8 feet), a floor plan with poor traffic flow, only one bathroom in a 3+ bedroom home, no garage in a market where garages are standard, and outdated electrical (60-amp service, knob-and-tube wiring).
Presenting Condition Evidence at Your Hearing
Organize your condition evidence into a brief written summary: 'The subject property has the following condition issues that reduce its value below the neighborhood average.' List each issue, the estimated cost to cure, and the resulting value impact. Attach photos and contractor estimates as exhibits.
Do not exaggerate condition issues. Assessors and board members have seen thousands of properties and can spot inflated claims. Present only genuine, documented issues with realistic value impacts.