California’s AI Plan Review — For Cities and Builders

We Have a Housing Crisis.
CrossBeam Solves It.

Two sides of the counter, one review: CrossBeam reads full plan sets against California law and your city’s code. Cities draft corrections letters in hours instead of weeks. Builders catch the corrections before they’re ever written. AI drafts. Your people approve.

I’m with a CityI’m a Builder

Just have a permit question? Ask the CrossBeam Permit Assistant →

Hundreds of pages. Months of work. Compressed into hours.

A builder’s full plan set lands at the city — watch CrossBeam work the loop.

Demo results: 132 sheets read; 2 corrections, 1 flag promoted to a correction by staff, 1 pass. 1. Common wall rating not shown (CRC R302.2.2, Sheet A-2.1) — correction. 2. Window U-factors not scheduled (CEC 160.1(e), Sheet A-6.0) — flagged by the engine, promoted to a correction by staff. 3. Side setback meets zoning (AMC §18.06.090, Sheet A-1.0) — pass. 4. Stair riser exceeds maximum (CRC R318.7.5.1, Sheet A-4.2) — correction. Round 1: the city sends the corrections letter. The builder fixes every item with CrossBeam Corrections Analysis and resubmits. Round 2: the city verifies each fix and approves. The letter, the fixes, the verification — approved in two rounds, every step through CrossBeam.

1st Place — Anthropic’s Claude Code Hackathon 2026 · 13,000 applicants

How It Works

Four steps. A human always reviews before anything goes out.

1

Upload Plans

Drag and drop a plan set or a corrections letter. PDF, any size.

2

AI Reviews

CrossBeam reads every page and cross-references California law and your city’s municipal code.

3

Draft Generated

A corrections letter — or a builder’s pre-check report before submittal — drafted with code citations and sheet references.

4

Human Reviews

Your staff reviews, edits, and approves. Nothing goes out without a human sign-off.

For Cities & Counties

Your plan checkers focus on judgment.

Applications come in faster than staff can check them — and local government has fewer plan-check hands than it did in 2020. CrossBeam drafts the corrections letter with code citations, under your letterhead, in your city’s own writing style.

  • Screen submittals at intake
  • Draft corrections letters in hours
  • Verify resubmittals against your own letter
CrossBeam for Cities

For Builders

Know what the city will say before the city says it.

In San Jose, nearly every plan set gets sent back for corrections — and every correction cycle costs months of lost rent, inflation, and loan carry. CrossBeam pre-checks your plans before you submit — and shows you the corrections letter the city would have written.

  • Pre-check before you submit
  • Decode a letter you already got
  • Scope a site before you draw
CrossBeam for Builders

Same Engine, Both Sides.

Everything above runs on CrossBeam Pre-Check — one review engine, purpose-built for plan check, that reads a plan set sheet by sheet the way a plan checker does. Around it, five tools that carry a permit from first question to final sign-off.

40+ permit types494 California jurisdictions onboardedand growing — new cities and permit types every week

CrossBeam Pre-Check

Core · Cities & Builders

Every finding comes back as a fail or a flag — with the code section and the sheet it lives on. Fails go in the letter; flags go to your staff’s judgment.

Explore Pre-Check

Architectural miniature of a small home on a parcel — the kind of plan set Pre-Check reviews

Around the Engine

Screener

City

Pass/fail completeness check at intake, before a plan checker opens the file.

Permit Assistant

Cities & Builders

Code answers with citations — for staff, builders, and residents.

Scout

Builder

Scout any parcel before you commit: dimensions, zoning, codes, and what a build will take.

Corrections Analysis

Builder

The city’s letter mapped onto your plan set, response drafted.

Corrections Response

City

Resubmittals verified against your original letter, item by item.

One Plan Set, Two Timelines

  • 90%+ of plan sets get corrections in San Jose — Mercury News.
  • 35,800 fewer local-government workers than in 2020 mean fewer plan-check hands — UC Berkeley Labor Center.
  • Consultant re-review runs $150–175 per hour; the city eats $300–625 per correction round.
  • A 6-month permitting delay costs a builder about $30,000 in lost rent, inflation, and loan carry.
  • 429,503 ADU permits filed in California since 2018 — Shovels.ai.
  • A CrossBeam Pre-Check runs in about 30 minutes. The city still reviews — you skip the correction rounds and approval lands around Month 2 instead of Month 6.

Both sides lose. CrossBeam is on the side of more housing, built faster, built to code.

Watch the video that won the entire Anthropic hackathon.

Full corrections analysis on a real Placentia ADU permit — 14 items parsed, verified, and responded to.

Try It Right Now

Ask the Permit Assistant anything about California permits — setbacks, height limits, sprinklers, what permit your project even needs. It’s grounded in 16,000+ pages of state code and each onboarded city’s rules, drawn from research spanning 480+ California city codes.

Ask the Permit Assistant

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