5 Common Solar Installation Mistakes Homeowners Make (and How to Avoid Them)

Solar panels themselves rarely fail. What fails is bad installation: wrong tilt, missed shading, weak structure, no earthing, or no monitoring. Here are the five mistakes that come up most often when we audit other vendors' installations — and exactly what to demand from your installer instead.

Mistake 1: Wrong panel orientation and tilt

In India, rooftop panels should ideally face true south (not magnetic south) and tilt at an angle roughly equal to your latitude (e.g. ~25° in Jaipur, ~13° in Chennai, ~28° in Delhi). Many installers shortcut to a flat 10° mount or align with the building wall to look neat. The result: 8–18% lower annual generation.

Fix: insist on a written orientation and tilt design with a generation estimate (kWh/year). Reject "we will install whichever way fits the roof" answers.

Mistake 2: Ignoring shading from water tanks, parapets, or trees

Even partial shading on one panel can drop the output of the entire string by 30%+ if there are no string optimisers or microinverters. Installers under time pressure often skip shading analysis entirely.

Fix: demand a shadow analysis using tools like Solargraf or PVsyst, especially if you have parapet walls, water tanks, mobile towers, or tall buildings nearby. Consider a hybrid panel layout or microinverters/optimisers if shading is unavoidable.

Mistake 3: Substandard mounting structure

The mounting structure holds 25 years of cyclones, monsoons, and corrosion. Cheap installers use thin galvanised iron (GI) that rusts within 2–3 years in coastal or polluted air. The panels are fine but the rusted structure becomes unsafe and unsightly.

Fix: insist on hot-dip galvanised (HDG) steel, 80+ GSM coating, with stainless-steel fasteners. For coastal areas, request aluminium structures.

Mistake 4: No earthing or lightning protection

An ungrounded rooftop solar plant is a literal lightning rod. Yet many small installers skip earthing pits and lightning arrestors to save ₹4,000–₹6,000.

Fix: require a dedicated earthing pit for the DC system and a separate one for AC; a Type-2 surge protection device (SPD); and a lightning arrester for buildings above 9 metres tall. This is also a DISCOM commissioning requirement in most states.

Mistake 5: No monitoring or remote diagnostics

Without monitoring, a 15% drop in generation can go unnoticed for months. Cheap setups skip the data dongle that connects the inverter to the cloud.

Fix: insist on Wi-Fi/4G monitoring (Solarman, Sungrow Cloud, FusionSolar, etc.). Check that you can see daily yield from your phone before signing off.

Bonus: how to vet your installer

• Are they empanelled under PM Surya Ghar Yojana for your state?
• Can they show ALMM-listed panel models on their quote?
• Do they provide a written 5-year workmanship warranty (separate from manufacturer warranties)?
• Will they handle DISCOM net-metering paperwork in writing?
• Can they share photos and contacts of 3 nearby installations?

Siyag Group has installed solar systems across hundreds of homes and businesses with a focus on engineering quality, not shortcuts. Schedule a free site visit and see the difference.