Contour Survey

TRPA Land Coverage Calculator

A quick estimate of how much of a Lake Tahoe lot can be covered, how much is left, and what buying the difference from a land bank might cost. Estimate only. Not a TRPA determination.

From the deed, a recorded map, or a boundary survey. 1 acre = 43,560 sq ft.

Coverage basis

Classes run 1 (most sensitive) to 7 (least), set by soil and slope. Class 1b is stream environment zone.

Roofs, driveways, walkways, patios, compacted dirt and gravel. Use 0 for a vacant lot.

California Tahoe Conservancy, prices updated Dec 1, 2025: $7.50/sq ft for Bailey 4–7 or IPES 726+ parcels in the South Stateline and Upper Truckee areas; $25.00 for more sensitive receiving parcels. Conservancy transaction fees are extra.

Estimate

Base allowable coverage
2,500 sq ft10,000 × 25%
Room left under base allowable
1,000 sq ft
Coverage you would need to buy
500 sq ft
Estimated land bank cost
$3,750

This is an estimate, not a TRPA determination. Actual allowable coverage depends on a TRPA-verified land capability or IPES score, verified existing coverage, limits on how much coverage can be transferred onto a parcel, excess coverage mitigation, and the exemptions in TRPA Code Chapter 30. Land bank prices vary by hydrologic area and change over time.

How the estimate works

  1. Base allowable coverage = lot area × percentage. The percentage comes from the parcel's land capability class (1 to 7, set by soil type and slope, worth 1 to 30 percent) or, for a vacant lot, the percentage TRPA issued with its IPES score.
  2. Room left = base allowable − existing coverage. Existing coverage is every roof (overhangs reduced), deck, driveway, walk, patio, and patch of compacted dirt or gravel.
  3. Shortfall × land bank price = estimated cost. If your plan needs more than the base allowance, the difference is what you would transfer in or buy.
ClassBase allowable
1a, 1b, 1c1%
21%
35%
420%
525%
6, 730%

What it leaves out

  • Whether your existing coverage is legally existing (created before February 10, 1972, or permitted and on site by October 15, 1986). Verified excess coverage can be kept; unverified coverage gets no credit.
  • TRPA's cap on total coverage reachable through transfers, which depends on parcel size.
  • The general prohibition on additional coverage in land capability Classes 1 through 3.
  • Excess coverage mitigation fees, exemptions, and the IPES one-third-acre building site rule on larger lots.

For real numbers you need a verified land capability or IPES score and a measured site plan. See TRPA land coverage surveys, when you need a site assessment, and what an IPES score means.

Realtors and designers: link to this page freely. URL: https://www.contour-survey.com/tools/trpa-coverage-calculator

Tahoe Coverage & Buildability Resources

Guides, a calculator, and survey services for TRPA land coverage on the California side of the basin.

TRPA land coverage surveysSite assessments, land capability vs. coverage verification, IPES, and legally existing coverage.Guide: Do you need a TRPA site assessment?When you need one, when you don’t, where to file, and what to submit.Guide: What an IPES score meansHow to look it up on Parcel Tracker and what it means for a vacant lot.Tahoe lot buildability surveyPre-purchase package for vacant lots: IPES, coverage, topo, and setbacks before the contingency ends.

Want the Real Numbers?

Send the APN. We check the TRPA record and measure what's on the ground. (510) 543-2220 · info@contour-survey.com

Get a Quoteor(510) 543-2220

California side of the basin • Licensed California surveyor • Response within 24 hours