n8n Construction Risk Triage: Sheets, Open-Meteo & Gemini

Know construction schedule & cost risk before it becomes a problem—automatically

This n8n workflow runs every weekday morning to triage construction delivery risk using Google Sheets, a 7-day Open-Meteo weather forecast, and Google Gemini—then logs a structured escalation decision and emails the project manager when intervention is needed.

What this workflow does

• Schedules execution at 7:00 AM, Monday–Friday via cron.
• Reads active projects from the Google Sheets Projects tab (projects marked Active).
• Pulls 7-day forecasts from the Open-Meteo API for each project using its latitude and longitude.
• Loads supporting data from other tabs in the same spreadsheet, including budget/accounting, procurement, labor, site reports, and disputes.
• Computes risk metrics across schedule, procurement, labor, disputes, weather, reporting integrity, and budget risk—then derives a rule-based decision: CONTINUE, INTERVENE, or STOP_REVIEW, including the most impactful mitigation lever and deadline.
• Validates the decision with Google Gemini by generating a structured decision JSON (headline, reasons, critical action, confidence) while applying guardrails for overrides.
• Logs results by appending each decision to the Google Sheets Decision_Log tab.
• Emails only when needed: the project manager receives a Gmail message when the decision is INTERVENE or STOP_REVIEW.

Use cases

• Daily executive triage for multi-site construction programs tracking budget, procurement, labor, and disputes.
• Escalation when weather risk (from Open-Meteo) threatens delivery timelines and budget integrity.
• Operational teams needing consistent, auditable escalation records in Google Sheets with Gemini-structured explanations.

Technical details

• Integrations: Google Sheets (Service Account access), Open-Meteo (HTTP Request), Google Gemini, Gmail.
• Workflow components: code, http request, filter, limit, and messaging/notes via sticky note.