Every November the Highveld sky turns charcoal, the wind smells like wet asphalt, and suddenly ice-pellets the size of half-chewed chappies start punishing rooftops from Krugersdorp to Kempton Park. Gauteng and Pretoria record the highest severe-hail counts in South Africa—33 and 29 big storms respectively since 1911. Add the fact that hail season peaks mid-November to February, 13:00–17:00 on most afternoons, and you’ve got the perfect recipe for roof carnage (santam.co.za). Luckily, you don’t need to sacrifice another insurance excess. Here are seven battle-tested tactics to toughen up your Chromadek® (or any steel) roof before the next cloudburst whistles down the N1.
1. Go Thicker Gauge or Go Home
Hail resistance scales with sheet thickness. Move from entry-level 0.40 mm (≈ 29 gauge) to 0.53 mm (≈ 26 gauge) and you jump an entire impact class—from “meh” to “bring it on”. Premium 0.58 mm (≈ 24 gauge) earns roofs a Class 4 hail rating—tested to survive a 50 mm steel ball at 70 km/h.
Wallet whisper: that extra ~R18 /m² now is cheaper than replacing dented pans later.
2. Pick a Deep-Rib Profile (IBR for the Win)
Deeper ribs = more rigidity and fewer flat spots for hail to bruise. IBR’s 36 mm ribs out-muscle corrugated’s shallow 17 mm waves, shedding both ice bombs and ponded water. Pair the profile with the thicker gauge above and you’ve already halved your dent risk.
3. Lock It Down With EPDM-Bonded Washers
Storm-wind uplift loves to wiggle loose screws; once a washer fails, hailwater sneaks in. Swap cheap plated washers for EPDM-bonded stainless screws—the rubber ring flexes under impact, maintaining a watertight seal even when ice hammers the sheet. bondedwasher.com Bonus: EPDM shrugs off UV, so it won’t crack by next season.
4. Add a Blanket Underlay—Noise Down, Dents Dampened
A 135 mm mineral-wool or 40 mm PIR board under the sheet does double duty:
- Absorbs impact energy, reducing the chance of micro-dents.
- Cuts hail racket by 10–15 dB, saving your pets (and nerves).
It also meets SANS 10400-XA insulation regs, so you’re legal and cosy.
5. Keep Gutters & Downpipes Hail-Ready
A hail-clogged gutter is basically a kiddies’ pool glued to your fascia:
- Install leaf-guards or expanded-metal screens—hail bounces off, leaves slide over.
- Oversize downpipes (100 mm+ round) so slushy ice flows out before it dams.
- Anchor gutters with extra brackets at 600 mm centres; ice is heavy.
Less overflow means fewer back-flows under roof sheets during the storm’s grand finale.
6. Shield Vulnerable Extras—Skylights & PV Panels
Polycarbonate skylights can handle hail up to ± 25 mm, but Gauteng occasionally lobs 40 mm stones. Fit:
- Mesh hail-screens above skylights.
- Aluminium perimetre flashings to stop ice splinters scratching the panels.
- PV arrays? Use hail-rated tempered glass and keep panels 50 mm clear of the sheet so stones decelerate before impact.
7. Book a Pre-Storm Roof Audit (and Snap the Evidence)
Insurers love proof. Schedule an August/September inspection to:
- Replace perished sealant and cracked flashings.
- Check screw spacing per SANS 1273 (five per sheet in edge zones).
- Log high-res photos—should any freak hail destroy your gutters, you’ll have “before” evidence and zero claim argy-bargy.
Quick-Reference Checklist
| Task | DIY Time | Cost (Indicative) | Hail-Proof Boost |
|---|---|---|---|
| Upgrade to 0.53 mm sheets | N/A (new install) | +R18 /m² | ★★★★☆ |
| IBR profile over corrugated | N/A | Similar price | ★★★★☆ |
| EPDM washers | 1 afternoon | R1 – R2 each | ★★★☆☆ |
| 135 mm insulation blanket | Install time = roofing | R35–R45 /m² | ★★★☆☆ |
| Leaf-guards & 100 mm downpipes | 2 hrs / 10 m | R40–R60 /m | ★★☆☆☆ |
| Skylight hail-mesh | 30 min | R300 – R500 / m² | ★★☆☆☆ |
| Annual pro audit | Half-day | R0 (we do it free) | ★★★★★ |
Final Word
Hailstorms may be a Highveld rite of passage, but a dented, leaking roof doesn’t have to be. Beef up the gauge, lock it with EPDM, insulate like a pro, and give gutters some gym time—then sit back with a hot chocolate and enjoy nature’s ice fireworks.
Need Backup?
Book our FREE Storm-Season Roof Readiness Scan. We’ll pop up the ladder, tick every item above, and hand you a photo-rich report—no obligations, just peace of mind.
