Timeline

Phase 1 ESA Timeline: Week-by-Week Due Diligence Milestones

A predictable Phase 1 ESA timeline helps brokers, buyers, and lenders align PSA dates, financing conditions, and environmental risk conversations.

Typical Week-by-Week Flow

  • Week 0: LOI / lender engagement — confirm ASTM E1527 scope and award consultant
  • Week 1: Records review begins — historical aerials, directories, regulatory databases
  • Week 1–2: Site reconnaissance — exterior (and interior if agreed) inspection
  • Week 2: Interviews and gaps list — owners, occupants, local knowledge
  • Week 2–3: Draft report and REC conclusions — lender formatting if required
  • Week 3+: Phase 2 scoping (if RECs) — separate schedule and budget

Aligning With Closing

Many teams target draft Phase 1 delivery at least 10 business days before hard closing so lenders can review REC language and request clarifications.

FAQ

When should I order a Phase 1 ESA in the transaction timeline?

Immediately after LOI or upon lender environmental checklist issuance—whichever comes first for financed deals.

What is the longest part of a Phase 1 ESA timeline?

Historical records research for older urban parcels or sites with fragmented ownership history.

Can Phase 1 and Phase 2 overlap on the timeline?

Sometimes buyers negotiate Phase 2 access while Phase 1 is in draft, but lenders usually need finalized Phase 1 REC conclusions before approving Phase 2 scope.

Related guides

Phase 1 ESA cost guide · Cost calculator · All guides