Before a single solar panel ever gets hauled up a ladder, there’s a crucial step that sets the stage for a smooth, profitable solar project or a series of costly headaches: the solar plan sets.
Precise solar plan sets are the foundation of every successful solar installation, and accurate jobsite documentation is the foundation of a great plan set process. Developing a standardized, streamlined process will protect you from hours of rework and weeks of project delays due to inaccurate documentation.
This guide is your complete manual for getting solar plan sets done right. We’ll cover the essential requirements (e.g., Authorities Having Jurisdiction (AHJs)), the components, and the best practices that will save you time, money, and frustration.
Understanding solar plan sets: Why they’re critical for your projects
Solar plan sets are the official blueprint for every solar installation. Skimping on your plan set package leads to delays, rework, and lost profits. Getting solar plans right is vital for meeting project requirements.
More than just drawings: The real job of a solar plan set
A solid solar plan design is a key communication tool. It ensures your crew, the building department, and the utility are aligned on the electrical layout, key components, and component positions. Good communication between installers starts here.
Why nailing your plan set is non-negotiable
Quality solar plan sets boost profitability. Fewer errors mean faster approvals from the Authority Having Jurisdiction.
Studies, like those published in Energy Policy, show that the median time from permitting application to final approval of a solar project with an AHJ can be around 50 days. However, this time frame can vary widely, sometimes stretching into several months, with a major factor being the quality and accuracy of the solar plan set you submit.
The good news is that, according to the National Renewable Energy Lab (NREL), some AHJs are now implementing automated approval software platforms like SolarAPP+ that can cut down approval times from that 50-day average to practically zero for compliant PV plans.
Successful use of this permitting process, where available, hinges on submitting adequately standardized solar plans to the local AHJ, leading to quick turnaround times and consistent quality.
The essential components of a bulletproof solar plan set
A bulletproof solar plan set includes these necessary components for smooth approvals and installations.
The cover sheet
The cover sheet is your solar project’s first impression. It must list:
- The project address and owner info
- Your company details and professional engineer/designer info
- The scope of work and sheet index for the plan set package
- The pertinent codes, project details, spec sheets, and references
The site plan
The site plan shows where the solar energy system components go. Accuracy is key, and it includes:
- Property lines, building footprints, and the arrangement of buildings
- Locations of inverters, disconnects, and meters
- Access points, specific city requirements
- Proposed array layouts for solar panels
- Obstructions affecting solar design
The roof plan and structural details
This proves the roof can handle the solar installation, detailing solar module placement and attachments. It often needs structural calculation documents.
- Dead loads, snow loads, and mph winds calculations (often by structural engineers)
- Roof framing plan or existing structure documentation
- Mounting hardware/flashing specs
- Calculations for panel support
- Attachment point locations
Electrical diagrams
The electrical diagrams detail all electrical components and wiring configuration in your solar energy systems, adhering to electrical codes.
Single-line diagrams (SLD)
The SLD (or one-line diagram) maps power flow from solar modules to the grid.
The single-line diagram shows:
- Key equipment details: PV modules, inverters (with inverter input), disconnects, overcurrent protection
- Grounding, connections between panels, and string layout
- Wire types and sizes for electrical wiring
- Path of power
Accurate solar panel wiring specs are vital.
Three-line diagrams (Optional but good to know)
A three-line diagram offers more AC/DC detail, showing individual phases for 3-phase power or complex electrical details like bidirectional power flow, if requested, or for battery energy storage systems.
Equipment specifications and electrical schematics
Include spec sheets for solar modules (e.g., for 25-30 panels), inverters (maybe central inverter specifications), racking, or backup panels. Electrical schematics might be needed for detailed internal wiring configuration.
Placards and labeling details
Clear, code-compliant labeling is a must for every solar installation. Detail placard text and locations for code compliance with electrical codes and local city codes.
You’ll need labels for:
- Ground fault indicators
- Interconnection points
- Arc fault requirement
- Rapid shutdown
- Disconnects
- Inverters
- Conduit
Additional documents
Your plan set package might also need:
- Structural calculation reports, possibly with engineering stamps (wet stamps) from licensed engineers/structural engineers
- Details for ground mount systems or battery storage plans, or battery installations
- Utility forms for the interconnection agreement
- Engineering letter or certification letter
- Datasheets for equipment details
The solar plan set design process: From site visit to stamped plans
Creating a solid solar plan set is a step-by-step game. Get one step wrong, and the whole solar design can suffer. Here’s the basic rundown of the solar plan set design process to keep your time frame for engineering review on track.
Step 1: The site assessment
This is where boots hit the ground for your solar project. Accurate measurements, clear photos of the roof, electrical panel, and any obstructions are non-negotiable for a good base plan. This is the foundation for all solar panel drawings.
To nail this crucial first step, using a tool like SiteCapture for your solar site assessments is a game-changer.
You can tag and manage all your on-site photos, use customizable site assessment checklists to ensure nothing is missed, and utilize live communication tools to keep your office team in the loop.
Getting these additional project details right during the acquisition of building information prevents headaches later.
Step 2: System design and layout
With accurate site data, your engineering team can work on the optimal array layouts and configuration of modules. This involves selecting the right solar energy systems equipment and planning the initial string layout and wiring paths.
System design also involves sizing the array to generate the required amount of power for each application. Specialized tools like Aurora Solar Design Software, combined with resources like the National Solar Radiation Database from NOAA, NREL’s Solar Supply Curves, and the Global Solar Atlas, can help accurately model energy output for different layouts.
Step 3: Engineering and calculations
Now, the serious number-crunching for your solar plans begins. This includes structural calculations to ensure the roof can handle the additional load. Electrical engineering calculations for things like voltage drop, wire sizing, and conduit size are also vital. Load calculations and complete load specs are critical for safety and code compliance, often handled by structural engineers or licensed engineers.
Step 4: Drafting the plans
This is where all the design work, calculations, and site information come together into the actual solar panel drawings and documents. Every detail, from the electrical plan to the roof framing plan, needs to be clearly and accurately represented in your common or basic plan. This forms your complete PV plans.
Step 5: Quality control and review
Before anything goes to the AHJ, a thorough internal review or even a 40-point quality review is essential. Catching errors in your solar plan sets now saves you from costly plan check rejections and delays later.
Step 6: Professional engineering (PE) stamps
Many jurisdictions require professional engineering review and PE engineering stamps (structural or electrical engineering stamps) on solar plan sets. This is especially true for complex projects or areas with specific environmental conditions like high winds. These wet stamps or digital equivalents are often needed for certification fees and signify that a licensed engineer has reviewed and approved the design.
Navigating AHJ requirements and permitting
Dealing with the Authority Having Jurisdiction and the solar permitting process can feel like an uphill battle:
- The US Department of Energy (DOE) notes there are 40,000+ building permit jurisdictions, plus more than 3,000 utilities in the US.
- NREL points to around 20,000 distinct jurisdictions involved in solar installation permitting, each potentially with its own way of doing things.
These numbers imply an average of roughly 400–800 AHJs in every US state. This makes the permitting process a frustrating patchwork for solar installers trying to get solar systems approved.
Understanding your local AHJ: No two are exactly alike
The hard truth is that AHJ requirements can change dramatically from one town to the next, even if they’re right next door. What flies in Maricopa County might be different in Pinellas County or Clark County, NV.
One building jurisdiction might have a specific setback rule for solar panels, while another has a different structural requirement based on local wind maps. For example, one county might demand a 3-foot fire setback from all roof edges, while its neighbor only requires it on the sides. These requirements directly impact your array layouts.
Always verify local city codes and building codes before you finalize your solar plan designs. Don’t rely on assumptions.
Key code requirements to keep on your radar
While local rules vary, most AHJs base their permit requirements on the National Electrical Code (NEC), along with state and local amendments. However, NEC adoption is still patchy, with six different versions adopted in different US territories and a few states with no statewide adoption, as the following map from Electrical Safety Foundation International shows.
So, when developing your solar plan set, pay close attention to:
- Specific cabling requirements or conduit requirements
- Adherence to building codes and local amendments
- Fire safety setbacks and clearance requirements
- Arc fault requirement and ground fault protection
- Rapid shutdown rules
The permitting process: A step-by-step (simplified)
Generally, getting your building permit involves:
- Submitting your solar plan set and application
- The AHJ performs a plan check
- Addressing any corrections
- Once approved, performing the solar installation
- Scheduling and passing inspections by the building official or city building office
If your AHJ has adopted SolarAPP+, this process can be much faster for eligible residential PV plans, with instant approvals possible. It’s worth encouraging your local AHJs to explore such technologies to streamline the permitting process for everyone and improve approval rates.
Dealing with plan check corrections
If your solar plans come back with corrections, don’t get discouraged. Communicate clearly with the building department, understand their concerns, and address them promptly and accurately. Ensuring compliance with code requirements from the start minimizes this, but quick, clear responses help when revisions are needed to keep your turnaround time short.
Common mistakes that will cost you time and money (and how to avoid them)
Avoid these common solar plan set slip-ups to prevent additional costs:
Mistake #1: Inaccurate site information
Bad data for your base plan ruins your solar design. Photodocumenting details like the electrical panel with SiteCapture ensures accurate project details.
Mistake #2: Ignoring local AHJ quirks
A generic common plan won’t pass if it ignores specific city requirements or building codes. Each building jurisdiction is unique.
Mistake #3: Sloppy or incomplete electrical details
Errors in electrical schematics or wiring configuration (i.e., wire sizes, protection) are inspector red flags. Vague electrical details or conduit requirements cause issues.
Mistake #4: Underestimating structural requirements
Incorrectly calculating dead loads, snow loads, or wind loads in your structural calculation is a safety risk. Don’t ignore structural details.
Mistake #5: Poor communication with your plan set provider
If you outsource to a plan sets service, ensure clear project requirements and site specifics. SiteCapture helps streamline field data collection for your engineering team or provider. By having all the data and details organized and centralized, SiteCapture helps to ensure simple, clear communication.
Software and engineering considerations for top-notch plan sets
Smart tools and expertise improve solar design quality and efficiency, embracing the power of automation for accurate plan sets.
Leveraging solar design software
Software like Aurora Solar Design Software (or Legacy Aurora) aids in array layouts, shading analysis, energy output estimates, and creating solar plan designs for solar energy systems.
Solar project management tools like SiteCapture also help streamline the initial site survey process by providing features for comprehensive data collection, photo documentation, and team collaboration, ensuring accurate information flows into the solar plan set creation.
The value of engineering expertise
For commercial projects, complex structural issues, or tricky utility requirements like complex utility interconnections, use a professional engineer (structural engineers or electrical PEs) for sound solar plans and necessary engineering stamps.
Your bottom line on solar plan sets
Look, we know that creating detailed, accurate solar plan sets takes time and effort, whether you do it in-house or use a trusted plan sets service. But that upfront investment in quality plan sets pays off big time. It means smoother approvals, fewer headaches on site, safer solar installations, and happier customers.
The good news is that the solar industry recognizes these challenges.
Initiatives like NREL’s SolarAPP+ are making headway in simplifying the permitting process in participating areas, and your own commitment to quality will always set you apart. You’ve got the skills to install top-notch solar systems. So, make sure your paperwork reflects that same level of professionalism.
Ready to streamline your solar projects? Start your free SiteCapture 14-day trial today or schedule a demo to experience smoother site surveys and more efficient data management for your solar plan sets.
