Roof Cleaning

Industrial & Commercial Roof Cleaning

Nobody sees an industrial roof. There's no kerb appeal at 8 metres, and no client is going to admire your sheeting. So why clean it? Because on a large roof, the dirt isn't just sitting there looking untidy — it's holding moisture against the steel, migrating into your gutters, absorbing heat you're paying to remove, and hiding the damage you'd want to catch early.

What Dirt Actually Costs You on a Big Roof

• Lost drainage capacity — everything that lands on the roof eventually washes into the gutters and outlets, and stays there
• Retained moisture — debris and organic growth hold water against the sheeting long after the rain stops, and that's exactly where corrosion begins
• Lost reflectivity — a darkened, grimy roof absorbs far more heat than a clean one, pushing up the temperature inside and the cooling load with it
• Reduced solar output — panels lose yield to dust and soiling, and a dirty roof keeps re-depositing it
• Coating degradation — lichen and moss don't just sit on a coating, they root into it and break it down
• Contamination risk — in food, pharmaceutical and packaging facilities, roof debris and bird fouling are a compliance problem, not an aesthetic one
• Ponding on flat roofs — blocked outlets leave standing water sitting on a membrane that was never designed to hold it
• Hidden damage — you cannot assess corrosion, failing laps or loose fixings through a layer of grime

The Pressure-Washing Problem

Here's where most industrial roof cleaning goes wrong. The instinct is to reach for the highest pressure available and blast the roof clean. On a coated metal roof that's one of the more effective ways to damage it.

High pressure strips protective coatings, blasts sealant out of joints, and — worst of all — forces water up under the laps, against the direction the roof was designed to shed it. That water doesn't run back out. It sits in the lap and corrodes the sheet from between the layers, somewhere nobody will look until it's a leak. Aimed at a fixing point, high pressure will also push water straight past the washer and into the building.

Competent cleaning works the other way around: pressure matched to the substrate, always worked down-slope with the laps rather than against them, and chemistry doing the work that brute force shouldn't. A correctly specified biocide or detergent given time to dwell will lift growth that no amount of pressure will remove safely — and it kills the spores, so it stays clean longer.

Different Roofs, Different Methods

There is no single roof-cleaning method. The substrate decides the approach:

Skylights and polycarbonate sheeting are worth doing at the same time and worth doing gently — no abrasives, no aggressive chemicals. Clean roof lights make a genuine difference to natural light levels inside, which is one of the few roof-cleaning results your staff will actually notice.

The Cheapest Inspection You'll Ever Get

Cleaning is the one job where somebody covers every square metre of your roof on foot. That's a full condition survey happening whether you ask for it or not — fixings, laps, corrosion spots, flashings, penetrations, gutters, skylights, all of it inspected at arm's length.

So ask for it. A clean that comes back with a written report and photographs of what was found turns a housekeeping expense into a maintenance decision: what needs attention now, what to budget for, and what's fine. A clean without one is a wasted trip up.

Doing It Without Stopping Production

Sicon Group cleans industrial and commercial roofs across South Africa, on live sites, without shutting operations down. Where access is difficult, our rope access teams work without scaffolding. Run-off is managed, open penetrations are protected so nothing finds its way inside, and work is scheduled around your shifts rather than the other way round. Every clean comes with a report on the roof's condition — because the point isn't a tidy roof, it's a roof you know the state of.