Black Bitumen vs Galvanised Star Pickets — Which Lasts Longer?

When you're ordering star pickets, one of the choices you'll face is finish: black (bitumen coated) or galvanised. Both work. Both are used across millions of kilometres of Australian fencing. But they're different products at different price points, and the right choice depends on your situation.

WHAT'S THE DIFFERENCE?

Black (bitumen) pickets: These are steel pickets dipped in a bitumen coating — that black, slightly sticky finish you see on most rural pickets. The bitumen acts as a barrier between the steel and the elements.

Galvanised pickets: These are steel pickets coated with zinc through a hot-dip galvanising process. The zinc creates a sacrificial layer — it corrodes before the steel underneath does, giving much longer protection.

LIFESPAN

In the Central West NSW climate (hot, dry summers; cold, occasionally wet winters; generally low humidity), both finishes perform well:

Black bitumen pickets: 15-20 years in typical conditions. The bitumen coating degrades over time — it cracks and flakes, especially on the sun-exposed side and at the ground line where moisture contact is highest. Once the steel is exposed, rust sets in.

Galvanised pickets: 25-35 years in typical conditions. The zinc coating is more durable and self-healing — minor scratches in the coating are protected by the surrounding zinc through cathodic protection. It takes much longer for the coating to degrade to the point where the steel starts rusting.

In coastal areas (salty air) or high-rainfall regions, the gap between the two widens further — galvanised significantly outperforms bitumen in these environments.

COST COMPARISON

Here's where it gets interesting. Our current pricing:

165cm: Black $8.50 / Galvanised $10.00 (difference: $1.50)

180cm: Black $8.40 / Galvanised $13.00 (difference: $4.60)

210cm: Black $13.00 / Galvanised $10.00 (difference: galv is cheaper!)

240cm: Black $11.00 / Galvanised $12.50 (difference: $1.50)

At some sizes, the price difference is minimal. The 210cm galvanised is actually cheaper than the black bitumen — so if you're buying that size, galvanised is a no-brainer.

For the popular 180cm size, galvanised costs $4.60 more per picket. On a 1km fence at 5m spacing (200 pickets), that's $920 extra for galvanised. If galvanised lasts 10-15 years longer, that extra investment means you're not replacing the pickets within your lifetime.

WHEN TO CHOOSE BITUMEN

  • Budget is tight and you need maximum pickets for minimum outlay
  • The fence is temporary or will be relocated within 10-15 years
  • You're fencing a large area and the cost difference across thousands of pickets is significant
  • Inland, dry conditions where corrosion is slow

Bitumen pickets are perfectly good products. Most of the fencing in rural Australia uses them, and they give reliable service for 15-20 years in our climate.

WHEN TO CHOOSE GALVANISED

  • You want the fence to last 25+ years without replacing pickets
  • The fence is in a high-moisture area (creek flats, irrigation country, coastal)
  • You're building a "set and forget" boundary fence
  • The price difference at your required size is small
  • You're fencing a smaller area where the total cost difference is manageable

WHAT ABOUT POWDER COATED?

For our Jumbo pickets (210cm, 7.3kg), we also offer a powder-coated option at $25. Powder coating is extremely durable — it's a baked-on finish that resists UV, moisture, and impact better than either bitumen or zinc. It's typically used for high-visibility applications, yards, or anywhere presentation matters.

THE GROUND LINE PROBLEM

Regardless of finish, the ground line is where pickets fail. The constant cycle of wet and dry soil at ground level attacks both bitumen and zinc coatings. There's not a lot you can do about this except use heavier pickets (our 2.1kg/m pickets have more steel to rust through) and drive them to the correct depth.

Some fencers paint the ground-line section with a rust-inhibiting paint before driving. Is it worth the effort? Probably not for a standard paddock fence, but for a premium homestead boundary or horse paddock, it adds a few extra years.

OUR RECOMMENDATION

For most rural fencing across the Central West, black bitumen pickets give great value. They'll see out 15-20 years, and by then you'll probably want to update the fence anyway. If you're building a boundary fence you want to last a generation, step up to galvanised — especially at the sizes where the price difference is small.

Either way, we carry both in all standard sizes. Drop in to 76 Astill Drive, Orange, or call 0434 093 077 to discuss what suits your job.

INSTALLATION AND MAINTENANCE CONSIDERATIONS

Beyond initial cost and lifespan, there are practical differences worth considering. Black bitumen Outback Pickets are slightly easier to handle during installation — the coating provides better grip and is less likely to cut your hands compared to the sharper edges sometimes found on galvanised pickets. However, in hot weather, the bitumen can become quite sticky and may transfer onto gloves and tools.

Galvanised Outback Pickets maintain their appearance longer, staying relatively clean-looking throughout their service life. Black bitumen pickets can develop a weathered appearance as the coating ages, though this doesn't affect their structural integrity in the early years.

For temporary fencing applications (12 months or less), black bitumen pickets often make more economic sense. For permanent boundary fencing, infrastructure projects, or anywhere you want "set and forget" performance, galvanised typically provides better value despite the higher upfront cost.

MAKING THE RIGHT CHOICE FOR YOUR PROJECT

Consider galvanised Outback Pickets if you're dealing with:

  • Permanent boundary fencing
  • Coastal properties or high-rainfall areas
  • Commercial or infrastructure projects
  • Areas where maintenance access is difficult

Black bitumen pickets work well for:

  • Temporary fencing solutions
  • Budget-conscious rural fencing projects
  • Internal paddock divisions where replacement is manageable
  • Dry, inland locations with minimal salt exposure

FREQUENTLY ASKED QUESTIONS

Can I mix black and galvanised Outback Pickets in the same fence line?

Yes, there's no structural issue with mixing them. Some farmers use galvanised pickets at corners and gateways (high-stress points) and black bitumen for straight runs to balance cost and performance.

Do galvanised pickets interfere with electric fencing?

No, both galvanised and black bitumen Outback Pickets work equally well with electric fencing systems. The coating doesn't affect electrical conductivity through the fence wire.

Which performs better in bushfire-prone areas?

Galvanised pickets have a slight advantage as zinc has a higher melting point than bitumen. However, in severe bushfires, the extreme heat will damage either coating, though the steel structure typically survives.

Use our free fencing calculator to estimate your project, or give Jess a call on 0434 093 077 for expert advice.

Back to blog