When Gauteng’s summer clouds roll in with ice-pellets the size of chappies, you want a roof that won’t fold like Bafana in a penalty shoot-out. Today we pit South Africa’s three most popular steel profiles—IBR, Corrugated and Widespan—against the brutal realities of Highveld weather in a four-round “Hail-Mary Test.” Grab your vuvuzela; let’s pick a winner.
Meet the Contenders
| Profile | Effective Cover | Rib Height | Min Roof Pitch (≤ 30 m span) | Typical Gauge Range |
|---|---|---|---|---|
| IBR | 686 mm | 36 mm | 5 ° (7.5 ° > 30 m) (specifile.co.za) | 0.4 – 0.8 mm |
| Corrugated | 762 mm (10.5) | 17.5 mm | 7.5 ° (10 ° > 15 m) (clotansteel.co.za) | 0.3 – 0.8 mm |
| Widespan | 762 mm | 28 mm | 7.5 ° (10 ° > 30 m) (clotansteel.co.za) | 0.3 – 0.8 mm |
Cheat-note: Lower pitch tolerance = flatter, cheaper roofs (less timber = happy wallet).
Round 1 – Hail Resistance & Dent-Defence
–IBR’s beefy 36 mm ribs give it muscle: fewer but deeper channels help spread impact. Most suppliers tout IBR as “designed to withstand hail and high winds.”
–Corrugated loves nostalgia but its shallow 17 mm waves bruise easier; hailstones can dent between ribs. Older, thin-gauge corrugated is notorious for “golf-ball dimples.”
–Widespan falls between the two—taller ribs than corrugated, broader coverage than IBR. Strength improves if you up the gauge to 0.5 mm+.
Scorecard: IBR 9/10, Widespan 8/10, Corrugated 6/10.
Round 2 – Water Run-Off & Leak-Proof Pitch
Heavy Highveld cloudbursts unleash 50 mm+ in minutes. Steeper ribs = faster run-off.
–IBR at 5 ° is SANS-approved (with sealed laps) and copes with big volumes.
–Widespan also hits 7.5 ° for roofs < 30 m, but its wider pan speeds flow—great for rainwater harvesting.
–Corrugated needs a steeper 7.5–10 ° to avoid back-wash; mis-pitch it and hello leaks.
Scorecard: IBR 10/10, Widespan 9/10, Corrugated 7/10.
Round 3 – Wind & Uplift Survival
Gauteng spring storms clock gusts > 100 km/h.
–IBR’s box-rib geometry makes it a favourite for warehouses—excellent negative-pressure resistance.
–Widespan shares similar rib spacing but broader sheet = fewer side laps (less uplift risk if properly fixed with bonded washers).
–Corrugated relies on more fasteners per square metre; skip a screw and the wind finds a pry-point. Still solid if installed to spec, but labour cost rises.
Scorecard: IBR 9/10, Widespan 8/10, Corrugated 7/10.
Round 4 – Price, Speed & DIY Friendliness
| Metric | IBR | Corrugated | Widespan |
|---|---|---|---|
| Supply-and-fit from | ± R220–R350/m² | ± R190–R320/m² | ± R240–R360/m² |
| Sheets per 50 m roof | 73 | 66 | 65 (widest) |
| DIY Cut-&-Fit | Moderate (sharper ribs) | Easy (thin wave, simpler overlaps) | Similar to IBR |
Corrugated’s gentle profile is forgiving for weekend warriors, but wider Widespan means fewer sheets and screws—faster pro installs. IBR sits in the middle on price and labour.
Scorecard: Widespan 9/10, Corrugated 8/10, IBR 8/10.
And the Winner Is… IBR (By a Hair-Rib) 🏆
Total tallies (out of 40):
| Profile | Hail | Water | Wind | Cost/Speed | Total |
|---|---|---|---|---|---|
| IBR | 9 | 10 | 9 | 8 | 36 |
| Widespan | 8 | 9 | 8 | 9 | 34 |
| Corrugated | 6 | 7 | 7 | 8 | 28 |
Why IBR edges out: lowest pitch tolerance, stout ribs for hail, stellar wind resistance—and still competitively priced. Widespan is a close second if you crave installation speed and fewer laps. Corrugated remains the lekker budget classic but needs steeper roofs and diligent fastening.
When to Choose Which Sheet?
–Your roof is < 10 ° pitch or you’re in a hail alley → IBR.
–Big rural barn or long-span factory → Widespan (fewer sheets, rapid fit).
–Rustic cottage, curved awning, or tight budget → Corrugated (easy bull-nosing and charm).
Final Word
Whatever profile you fancy, the real Hail-Mary is expert installation: sealed laps, bonded washers, correct screw spacing. We stock, cut and bend all three profiles, plus flashings, gutters and storm washers that keep the Highveld weather where it belongs—outside.
👉 [Request a site-spec quote here] and let’s armour your roof before the next golf-ball hailstorm knocks.
