6 min read · Updated 1 August 2026
Commercial solar panel cleaning: a facility manager's checklist
A commercial solar cleaning contract should specify per-panel pricing, quarterly scheduling, working-at-height compliance, before-and-after generation reporting, and a defect report from a qualified electrician.
Price the way the work is actually done
Per-panel pricing is the only rate that scales honestly across sites. RobCon Electrical quotes commercial work from R25 per panel excluding VAT, which means a 400-panel warehouse roof is priced predictably rather than by a vague day rate.
For multi-site portfolios, ask for a single schedule of rates covering every site, with travel shown separately for anything outside Gauteng. That keeps comparison between quarters straightforward.
Schedule around production, not around the contractor
Warehouses, retail centres, hospitals and factories all have hours where roof work is disruptive or unsafe. Agree the working window up front and put it in the contract. We routinely clean outside trading hours and around shift patterns.
Quarterly is the right default for commercial roofs in Gauteng. Large flat roofs collect standing dust that dries into a hard crust, and the revenue at stake on a 100 kW-plus system makes waiting a full year an expensive decision.
Safety and compliance
Confirm the contractor carries public liability cover, works to a documented working-at-height method, and does not require your staff to supervise roof access. Ask how they protect roof sheeting and waterproofing, especially on older IBR and torch-on roofs.
Using a qualified electrical contractor rather than a general cleaning company matters here: the array is live DC at all times, and anyone handling cabling, connectors or isolators near it should be competent to do so.
Ask for a defect report, not just a clean roof
The clean is the visit; the inspection is the value. Every commercial visit should return a short written report covering loose or chafing DC cabling, corroded or arcing MC4 connectors, cracked or delaminating panels, visible hot spots, loose mounting hardware, and blocked drainage or debris build-up under the array.
Small faults found early on a roof you are already standing on are dramatically cheaper than the fire risk, insurance dispute or emergency call-out they turn into later.
Measure the result
Record peak generation on a clear day before and after each clean and keep the figures in a simple log. Over a year that log tells you whether your cleaning interval is right, and it turns the line item from a cost into a documented return.
It is also the number to take to your finance team. Recovered kWh at your commercial tariff, against a per-panel rate, is a straightforward calculation to defend.
Body corporates and estates
Complexes and estates get the best rate by quoting the whole site at once rather than unit by unit. Shared roofs also soil unevenly, so a site-wide clean avoids the situation where one block quietly underperforms for a year.
We are used to estate access and contractor rules, including sign-in procedures, induction requirements and restricted working hours.
Common questions
- Do you clean while the system is generating?
- Yes. Cleaning does not require shutting the array down, so there is no production loss during the visit. Where any electrical work is needed, we isolate properly first and agree the window with you.
- What is the minimum size for a commercial job?
- There is a minimum call-out rather than a minimum panel count. For sites outside Gauteng, the panel count generally needs to justify the travel, which we quote separately and show up front.
- Can you service multiple sites on one contract?
- Yes. Multi-site portfolios are quoted on one schedule of rates with a shared cleaning calendar, so the work happens on schedule without you chasing it site by site.
Want your panels checked?
RobCon Electrical cleans residential systems from R35 per panel and commercial from R25, across Pretoria, Centurion, Midrand, Johannesburg and greater Gauteng.