Installing solar panels is a smart move, but it’s easy to get things wrong if you’re not careful. From poor placement to wiring issues, small mistakes can lead to bigger problems later. In this blog, we’ll cover 10 common errors people make during solar installation—and how you can avoid them to keep your system safe, reliable, and cost-effective.
1) Rushing the site assessment
A quick look at the roof often misses key details. Many problems start here, then echo through the rest of the project. A complete site check should map roof age, structure, angles, and obstructions. It should also review local rules and utility needs. When this step gets rushed, later fixes cost time and money. Therefore, insist on a roof walk, attic look, and photos with notes on beam spacing, sheathing type, and access paths.
2) Overlooking roof health
Panels last a long time, so the roof beneath them must last too. Old shingles, soft spots, or loose flashing turn into leaks once racking goes in. Before any hardware touches the roof, schedule repairs or a re-roof if needed, then confirm proper flashing and sealant around every penetration. As a result, water stays out, and future work stays simple.
3) Sizing the system by guesswork
Guessing based on a single bill or on panel count alone often leads to shortfalls or waste. Accurate sizing starts with twelve months of electricity use, not a single season. It also considers future changes, such as an electric car or a heat pump. After that, convert those needs into system size using local sunlight data. Right-sized arrays hit savings targets while avoiding overspending on gear you do not need.
4) Ignoring shade and seasonal sun paths
Shade from trees, chimneys, or nearby buildings cuts output more than many people think. Winter sun rides low, so objects that look harmless in summer can cause deep shadows in colder months. Therefore, map shade for all seasons with a handheld tool or a simple solar path chart. Then, choose stringing and inverter types that handle partial shade with less loss.
5) Placing panels without a layout strategy
Panels work best when the layout supports both energy and service. Random rows make cleaning and repairs harder. Instead, form even rows with clear walkways so a person can reach every component. Keep gutters and skylights accessible. Maintain safe clearances from roof edges and ridges. With a thoughtful layout, wind loads stay balanced and future care becomes simple.
6) Cutting corners on mounting hardware
Strong panels still fail when rails, bolts, or flashings fall short. Hardware must match wind, snow, and corrosion demands in your area. Stainless fasteners, UV-resistant caps, and quality flashing reduce leaks and loose rails. Torque settings also matter, since over-tightening crushes wood while under-tightening loosens over time.
7) Skipping needed electrical upgrades
Older homes often need panel space, new breakers, or a service upgrade. Delaying this work risks nuisance trips or safety issues. Therefore, check the main panel rating, bus load, and breaker availability during planning. Provide a clear disconnect location that first responders can reach. These steps support safe operation and smooth inspections.
8) Mismatching the inverter type and site conditions
String inverters, microinverters, and DC optimizers each have strengths. A roof with mixed angles or partial shade may benefit from power electronics at each panel. A simple, unshaded roof may do well with a central inverter. In every case, pick one approach and keep parts consistent. Mixing unlike parts often complicates service and monitoring.
9) Sloppy wire management and weather sealing
Neat wiring does more than look good. It cuts wear, stops noise, and helps with troubleshooting. Cables should be clipped to rails, lifted off the roof, and protected at every edge. UV-rated conduit guards exposed runs. Tight grommets and sealed junction boxes keep water out. As a result, wind does less damage, pests stay out, and connections last longer.
10) Treating monitoring and maintenance as an afterthought
Even reliable systems deserve attention. Without monitoring, small issues hide until a bill spikes. Set up monitoring the day the system turns on and verify that data flows. Then, plan simple care: rinse dusty panels during dry spells, check for loose debris after storms, and inspect roof hardware every year. With steady care, performance stays strong and payback stays on track.
Helpful checks that prevent trouble
Balanced habits turn good plans into strong results. The following quick checks support safe work and steady output.
- Review a full year of utility bills and note any future changes in use.
- Confirm roof condition, flashing needs, and access paths with photos.
- Record tilt, azimuth, and shading for each roof face before layout.
- Verify main panel rating, breaker space, and shutoff locations.
- Label disconnects, meters, and combiner boxes for easy service.
Paperwork, codes, and utility rules often get skipped.
Permits and utility rules exist to keep people safe and the grid stable. When steps get skipped, projects stall or systems shut off. Read local code for roof setbacks, wiring methods, and markings. Submit interconnection forms with one clear, complete package. Schedule inspections early and keep drawings on site. Therefore, approvals move faster and crews finish work without avoidable delays.
Storage and Future Upgrades Deserve Room in the Plan
Many households add storage later for backup or time-of-use savings. Space in the electrical area, a clear wall room near the main panel, and conduit paths to a future battery make that step easier. Even without storage on day one, small choices during installation set the stage for growth. Thoughtful planning today reduces changes tomorrow.
Clear Labels and Simple Documentation Help Everyone
Labels save time when a fuse blows or a component needs a swap. Moreover, a short handover packet gives a homeowner confidence after the crew leaves. Include a one-page diagram, serial numbers, and warranty contacts. Add the monitoring login and a simple maintenance calendar. With this packet in a kitchen drawer, help arrives faster when needed.
Budget Choices that Support Long-Term Value
Lowest upfront price rarely equals best long-term value. Panels, inverters, and hardware carry different track records in heat, snow, and coastal air. Choose proven gear from brands with solid support and clear manuals. As a result, service remains available, parts ship on time, and downtime stays short. Money saved on fewer fixes tends to beat tiny savings on day one.
Simple Signs of a Job Done Well
Small details tell a clear story about the care put into an installation. Straight conduit runs show planning. Flush-mounted rails show careful measurement. Dry attic wood beneath every flashing shows proper sealing. Labeled shutoffs show regard for safety teams. Clean job sites show respect for your home.
Conclusion
A solar system rewards patience, careful checks, and steady care. Each step in planning, layout, hardware choice, wiring, and paperwork shapes the years that follow. With solid habits, sunlight turns into steady savings without stress or surprise. For a final, service-specific note, Tom’s Solar offers solar system installation for households that want a clear plan and careful work from start to finish.