Exhibit 01 · Choropleth
Every county, priced against its rebuild cost
Market
ZHVI · Jan 2026
Rebuild $/ft²
NAHB state × CBP wage idx
Size
State avg × bedroom ratio
Coverage
—
| County | Verdict | Market | Size | $/ft² | Rebuild | Q | Premium |
|---|
Scroll to zoom · drag to pan · hover for detail · click a county to pin it. Grey counties have no market data.
Exhibit 02 · Ranking
The tails: twelve most overvalued, twelve most discounted
Set
National · 24 counties
Sort
Premium · ascending
Scale
Diverging from zero
| County | Verdict | Market | Rebuild | Q | Premium |
|---|
Rows are buttons: select one to locate it on the Exhibit 01 map. Colour encodes premium over rebuild — the heat scale in the legend.
Method & sources
Rebuild cost is modeled, not published. No county-level construction-cost series is public. The county $/ft² and size figures below are documented estimates built on published state anchors — credible for a regional screen, not for appraisals.
- Market value: Zillow ZHVI county, all homes, January 2026 — the same vintage as the state map. 66 thin rural counties missing from ZHVI use the Census ACS 2024 5-year median owner-estimated value instead, marked *.
- Build cost:
county $/ft² = state NAHB-2024 $/ft² × (0.55 + 0.45 × wage index), where the wage index is county ÷ state mean construction payroll per employee (Census County Business Patterns 2023, NAICS 23), clipped to 0.7–1.6. Labour ≈45% of build cost; materials, equipment and regulation stay at the state level. Suppressed counties fall back to the state figure, marked †. - Home size:
county ft² = state avg size × (county ÷ state mean bedrooms)from ACS 2024 5-year table B25041, clipped to 0.72–1.35×, marked ‡ where bedrooms were unavailable. - Bands: deeply undervalued < −50% · undervalued −50…−20% · slightly undervalued −20…−10% · fairly valued ±10% · overvalued +10…+35% · highly +35…+70% · extremely +70…+150% · superstar > +150%.
- Sources: Zillow ZHVI county · Census CBP 2023 · ACS 2024 5-year summary file · NAHB 2024 via TXRAC/Homequirer · 2022 American Home Size Index · geometry: us-atlas counties.