Guttering & Stormwater

Industrial & Commercial Roof Guttering

A house gutter moves the rain off a few dozen square metres. On a warehouse or factory, the guttering can be draining thousands — and it has to do it during a Highveld thunderstorm that dumps its whole load in twenty minutes. When industrial guttering can't cope, the water doesn't politely wait. It goes over the edge, back under the sheets, or straight into the building.

Industrial Guttering Is a Different Job

The principle is the same as a domestic gutter, but nothing else is. The catchment area is enormous, the runs are long, the falls are shallow, and the volume arriving in a summer storm is far beyond anything a residential system is designed for. That changes what matters: the size of the gutter, the number and size of the outlets, the fall along the run, and whether there's anywhere for excess water to go when the system is overwhelmed.

Most industrial gutter failures we're called to aren't really failures of the gutter. They're failures of capacity — a system that was never sized for the roof above it, or one that has slowly lost capacity to silt, corrosion and blocked outlets.

Where Industrial Guttering Goes Wrong

• Undersized for the catchment — the roof sheds more water than the gutter can carry, so it overtops in every heavy storm
• Too few or undersized outlets — the gutter itself may be adequate, but the water can't get out of it fast enough
• Insufficient or uneven fall over long runs — water stands, silt settles, and the gutter corrodes from the inside out
• No overflow provision — nowhere safe for excess water to escape when the outlets can't keep up
• Failed joints and seals, especially where long runs need expansion joints for thermal movement
• Blocked outlets — leaves, windblown debris, bird nests and hail-shredded insulation are the usual culprits
• Sagging brackets and supports — a full gutter is extremely heavy, and once it sags the fall is gone for good
• Corroded downpipes that leak against the wall and quietly damage the cladding and foundations below

Box and Valley Gutters: the Ones That Flood Buildings

External gutters fail outwards — you get a waterfall down the side of the building and a wet apron. Internal box gutters and valley gutters sit inside the building envelope, and when they overtop or leak, the water goes directly into the roof space, onto racking, onto stock, or onto a production line.

These are the gutters worth being genuinely careful about. They need to be correctly sized, kept clear, sealed properly at every joint, and — critically — given a designed overflow so that when something does block, the water has an escape route that isn't your warehouse floor.

Repair, Line or Replace?

Replacing an industrial gutter system isn't always the answer, and it isn't always necessary. There are usually four routes, and the right one depends on what's actually wrong:

Keeping Them Working

Guttering is the part of a roof most easily kept in good order, and the part most often ignored until it fails. A basic regime:

• Clean before the rainy season — in most of the country that means getting it done in early spring, ahead of the summer storms
• Check every outlet and downpipe runs free — the outlets block long before the gutter does
• Inspect joints, seals and expansion joints for early signs of movement or leaking
• Look for standing water after rain — it means the fall has been lost somewhere
• Catch internal corrosion early, while lining or a localised repair is still an option

What Sicon Group Does

Sicon Group handles industrial and commercial guttering across South Africa — assessment and capacity checks, cleaning, repairs and resealing, gutter lining, and full replacement where the system genuinely isn't up to the roof it serves. Where gutters are high, awkward or over live operations, our rope access teams reach them without scaffolding or shutting the site down. Every job starts with finding out what's actually wrong, so you're not paying to replace a gutter that only needed clearing.