Every solar contractor knows the frustration of a permit rejection. Redlines from AHJs (Authorities Having Jurisdiction) not only delay projects but also increase costs and hurt client trust. The good news? Most redlines are preventable if you know what AHJs and utilities look for.
In this article, we’ll explore the most common solar permit redline mistakes and share practical solutions to help contractors submit approval-ready designs the first time.
Why Redlines Matter in Solar Permitting
- Delays Projects: Each resubmission can add 1–3 weeks.
- Increases Costs: Extra design revisions = lost time and money.
- Hurts Reputation: Clients lose confidence when “approval” keeps getting pushed back.
Avoiding redlines isn’t just about speed—it’s about building trust and efficiency in your solar business.
1. Incomplete Site Plans
The Mistake: Many submittals skip details like:
- Property lines
- Roof access pathways
- Setbacks from ridges/valleys
- Location of disconnects & inverters
The Fix: Always include a scaled, detailed site plan with clear labeling of equipment and pathways per IFC fire code.
2. Incorrect or Missing Electrical Calculations
The Mistake: Submitting generic one-line diagrams without proper load calcs, conductor sizing, or overcurrent protection.
The Fix:
- Follow NEC Article 690 (PV Systems) and Article 705 (Interconnections).
- Clearly show breaker sizing, conductor ampacity, and point of interconnection.
- Use utility-approved interconnection methods.
3. No Professional Engineer (PE) Stamps for Structural Loads
The Mistake: For commercial or large residential projects, structural loads are often required to be PE-certified. Submitting without a stamp leads to instant rejection.
The Fix: Always provide PE-stamped structural drawings when roof integrity, wind load, or snow load could be questioned.
4. Ignoring Local AHJ Amendments
The Mistake: Submitting a permit package based only on the NEC, without checking for city/county-specific amendments.
The Fix: Review the AHJ’s published codes. Example: Some regions require extra roof setbacks or stricter labeling beyond NEC.
5. Poor Labeling & Signage Plans
The Mistake: Submittals missing clear signage placement diagrams. AHJs want to know where every label goes.
The Fix: Include a labeling sheet with NEC 690-compliant verbiage and placement (e.g., disconnects, inverters, meters)
6. Utility Interconnection Oversights
The Mistake: Contractors often treat interconnection as “just paperwork” — but utilities can reject if load studies or protection devices are missing.
The Fix:
- Include interconnection diagrams in the permit package.
- Show protective devices like fuses, relays, or reclosers for larger systems.
- Coordinate early with the utility to meet their standards.
How Vishtik Prevents Permit Redlines
At Vishtik, we specialize in approval-ready permit designs that avoid costly redlines. Our process includes:
- NEC-Compliant Electrical Drawings: One-line & three-line diagrams with accurate load calcs.
- AHJ-Specific Packages: Custom-designed to meet local amendments and fire codes.
- PE-Stamped Engineering: Structural and electrical stamps for commercial or large residential projects.
- Labeling & Signage Sheets: Fully NEC 690.56-compliant.
- Utility Coordination: Interconnection documentation designed for fast approvals.
With Vishtik, contractors submit once and get approved faster.
Conclusion
Redlines are frustrating, but they’re not inevitable. By understanding the most common mistakes—incomplete site plans, missing calcs, lack of PE stamps, ignoring AHJ rules, poor labeling, and interconnection oversights—contractors can save time and deliver smoother solar projects.
Vishtik’s team of experts helps you avoid redlines, reduce project delays, and keep clients happy.
Ready to eliminate permit headaches? Work with Vishtik for approval-ready solar permit designs.
