How PlatNum works

Methodology, coverage & limits

PlatNum combines parcel facts, reviewed rules, geometry, and assumptions to compare residential concepts. It separates evidence, inputs, and verification gaps. It is an early screen—not a permit determination, professional opinion, or promise of outcome.

What you can screen today

From parcel to development decision

Search county parcels, compare residential concepts, and review capacity, economics, and diligence questions. Availability depends on parcel, jurisdiction, evidence, and rules.

Countywide parcel search

Search vacant and improved assessor parcels. Assessor labels do not establish allowed uses.

  • Bellingham
  • Blaine
  • Everson
  • Ferndale
  • Lynden
  • Nooksack
  • Sumas
  • Unincorporated Whatcom County

Residential concept generation

Compare existing improvements, ADUs, homes, duplexes, townhouses, apartments, short plats, and subdivisions—with rent or sale exits.

Feasibility and underwriting

Model site constraints, capacity, concepts, exits, returns, and supported land basis.

Where automation hands off

Commercial uses, tribal land, unclear zoning, complex overlays, title restrictions, access, and utility questions require review.

What we read

The evidence behind a result

Facts, rules, and assumptions stay distinct and traceable.

Parcel and assessment

County parcel boundaries, identifiers, property facts, assessed values, and sales.

Zoning and code

Published code and zoning maps, translated into traceable structured rules for use and dimensional constraints.

Geometry and buildings

Parcel geometry, mapped constraints, and multi-source building footprints.

Critical areas

Official GIS screens for wetlands, streams, flood, shoreline, water resources, and supported buffers.

Permits

Bellingham project records and countywide Census permit totals.

Listings and transactions

Listing snapshots, assessor transfers, and validated multifamily sales.

Market assumptions

Versioned rent, cap-rate, sale, and marketability assumptions with supporting evidence and confidence.

Costs and fees

Versioned construction costs and jurisdiction fees, separate from project quotes and overrides.

Finance assumptions

Explicit loan, rate, term, carry, and return inputs—not lender commitments.

Evidence and audit trail

How a result can be checked

Result-level citations

Material facts and applied rules identify their source where supported. Verify material facts with the source agency before acting.

Rule citations

Structured rules retain jurisdiction and citation so their application can be reviewed before proceeding.

Assumption provenance

Market assumptions retain evidence, confidence, and version. Customer overrides are labeled separately.

Report audit trail

Reports preserve the calculation, versions, inputs, and evidence used for the result.

Reading a result

What the answer can say

A gap is not the same as a “no.”

Feasible
Available inputs support the concept within modeled site and return constraints. Confirm material facts before acting.
Infeasible
A specific modeled envelope, density, access, parking, or return constraint is not met.
Insufficient data
A required input is missing or too weak to calculate. This is not a negative finding.
Source conflict
Relevant sources disagree; review the conflicting facts before proceeding.
Manual review
A planner, engineer, surveyor, utility, title, or other project-specific determination is required.
Out of coverage
The parcel, jurisdiction, use, program, or source is not supported.

Before you offer

What to confirm before you commit

Confirm material facts with the source agency and appropriate professional.

Listing coverage

Listings provide market context, not a complete market record. A missing match is not proof a property is off market.

Permit coverage

Project-level permits are Bellingham-only. Elsewhere, Census data provides aggregate totals—not individual records.

Critical-area screening

Mapped layers flag risk; they do not replace wetland, habitat, flood, shoreline, or agency review.

Building footprints

Multi-source footprints can be missing, shifted, or duplicated. Verify site conditions in the field or by survey.

Water and utility adequacy

PlatNum does not confirm utility capacity, water rights, wells, septic, or provider approval.

Site and legal facts

The screen does not replace survey, title, access, soils, fee, value, construction, or lender diligence.

Continue

See the method in action

Explore a representative result or follow the full workflow.