Azobe vs Greenheart: Strength, Marine Durability, Supply and Cost Compared

If you specify heavy timber for canals, harbours or bridges, the azobe vs greenheart question will come up sooner or later. These are the two great heavy marine hardwoods of the last century. Engineers in the Netherlands grew up with Azobe. Engineers in the UK grew up with Greenheart. Both have kept lock gates and quay walls standing for decades.

So which one should you choose today? In this guide we compare them on the points that matter on site and in the budget. We supply Azobe from Central Africa at Global Timber Trade Hub, and we will be honest about where Greenheart still has the edge.

Two heavyweights from two continents

Azobe (Lophira alata), also called Ekki or Bongossi, grows in the rainforests of West and Central Africa, including Cameroon, Gabon and the Republic of Congo.

Greenheart (Chlorocardium rodiei) grows mainly in Guyana, with smaller amounts in neighbouring countries. Its limited natural range is one of the reasons supply is tight.

Azobe vs greenheart at a glance

Values vary between sources and individual trees. Always design to the strength class stated in your national standard.

Strength and hardness

Both timbers sit in the top strength classes for hardwoods. Azobe is generally harder, which helps against abrasion from ships, ice and debris. That is one reason it is so common for fender piles and rubbing strips.

Greenheart is also extremely strong in bending and compression. For most structural designs, both can meet the same strength class, so the choice usually comes down to durability, supply and cost.

Durability in fresh water

In fresh water, both perform very well. Azobe has been used for canal banks, locks and weirs in the Netherlands and Germany for generations, with service lives of 25 years or more being common. Greenheart has a similar record on British canals.

If your project is in a river, a canal or a lake, Azobe is a proven and cost-effective choice.

Durability in salt water

This is where Greenheart has built its reputation. Marine borers, such as shipworm, can seriously damage timber in salt and brackish water, especially in warm seas. Greenheart is well known for its resistance to these borers.

Azobe performs well in temperate marine settings, but in tropical salt water with heavy borer pressure, engineers often prefer Greenheart or add protection. If your project is in such conditions, tell us and we will discuss options honestly, including alternatives like Bilinga, which has a good borer record.

Sizes and availability

Azobe trees are large and produce long, wide sections. We supply beams up to about 300×300 mm, in lengths up to about 12 m, plus planks, decking, sleepers and crane mats. Supply from Central Africa is steady, and container volumes are routine.

Greenheart supply depends on a smaller producing region. Large sections can be available, but lead times and prices are often higher, especially for big projects.

Cost per cubic metre

Prices change with section size, grade and volume, but Azobe is usually the more economical of the two. On our site, Azobe starts from about $650 per m³ for standard sawn sections, FOB Central Africa. For large public projects, that difference can be very significant.

See the full price list in our guide to African hardwood prices.

Working with Azobe and Greenheart

Azobe

• Very hard: use carbide or stellite-tipped tools and slow feed rates.
• Always pre-drill for bolts and nails.
• Dries slowly and can check; usually supplied fresh sawn or air dried.
• Gluing is difficult; use mechanical fixings for structural joints.

Greenheart

• Also very hard and heavy, with similar tooling needs.
• Splinters can be sharp and may cause irritation; wear gloves.
• Pre-drilling is essential.

Which one should you choose?

Choose Azobe if

• your structure is in fresh water or a temperate harbour;
• abrasion resistance matters, for example fender piles and crane mats;
• you need large volumes at a controlled budget;
• you want steady supply and shorter lead times.

Choose Greenheart if

• your structure is in warm salt water with high marine borer risk;
• the specification names Greenheart by tradition or standard;
• budget and lead time are less critical.

Other alternatives worth considering

When neither Azobe nor Greenheart fits, these species are often accepted in specifications:

• Okan: very hard and class 1 durable, a close Azobe alternative.
• Mukulungu: very heavy and durable, with a finer texture.
• Tali: dense and durable, economical for piles and sleepers.
• Bilinga: lighter, very durable and good against borers.

Our guide to the best wood for marine construction compares all of them.

Specifying Azobe correctly

To get the right timber, include in your tender or order:

• strength class and grading standard;
• section sizes and lengths, with tolerances;
• moisture condition: fresh sawn or air dried;
• allowed defects, such as end splits and heart;
• legality and, if needed, certification requirements;
• delivery port and schedule.

Legality and sustainability

Azobe is listed as Vulnerable by the IUCN, so legal and well-managed supply matters. We buy only from concessions with valid harvesting permits that respect minimum felling diameters, and every shipment includes legality and chain-of-custody documents. Read more on our sustainability page.

A typical decision on a real project

Consider a regional water authority rebuilding the fender system of an inland harbour. The original design called for Greenheart. Lead times and budget were both tight. Because the harbour is fresh water and borer risk is low, the engineer approved Azobe at the same strength class. The project kept its schedule and saved on timber cost, with the same expected service life.

A long history in Europe

Azobe arrived in large volumes in the Netherlands in the 20th century, when Dutch water boards were rebuilding locks, sluices and bank protection. Its strength and durability made it the standard heavy timber for hydraulic works there, and the same habit spread to Belgium, Germany and France. Greenheart followed a different path. It was shipped from British Guiana to the UK and became the classic material for British canal lock gates, piers and sea defences. Many engineers still specify the timber their predecessors used, which is why tradition plays such a big part in this choice.

How heavy timber is graded

For structural use, heavy hardwood is graded visually against a standard such as EN 14081 in Europe or BS 5756 in the UK. The grader checks slope of grain, knots, splits, wane and other features, then assigns a strength class such as D70 or D60. Both Azobe and Greenheart commonly reach the highest classes. Make sure your order states the strength class and the standard, not just the species. That way you can compare offers properly and accept alternatives when needed.

Handling and transport of heavy sections

A single Azobe beam of 300 × 300 mm and 12 m long weighs more than a tonne. That has practical effects. Containers fill by weight long before they fill by volume, so you ship fewer cubic metres per container. On site, you need cranes or heavy forklifts, and safe lifting points. Plan storage on level bearers, off the ground, to avoid distortion. We send exact weights with the packing list so your logistics team can plan.

Carbon footprint compared with steel and concrete

Hardwood stores carbon absorbed by the tree while it grew. Producing steel and concrete releases large amounts of carbon. For lock gates, fender systems and footbridges, a legally sourced hardwood structure often has a lower footprint than a steel or concrete one, even after allowing for sea freight. That is one reason why many public clients in Europe still choose timber for hydraulic works. Ask your engineer for a lifecycle assessment if this matters for your tender.

Lifecycle cost

When you compare Azobe and Greenheart, look at the whole life of the structure. Include purchase price, freight, installation, expected service life and the cost of replacing worn members. In fresh water and temperate harbours, both reach similar service lives, so Azobe’s lower purchase price usually gives a lower lifecycle cost. In tropical salt water, Greenheart’s borer resistance can justify its higher price because members last longer.

What we need to quote quickly

For heavy timber, the details matter. Send us a cutting list with sections, lengths and number of pieces, the strength class, the moisture condition and the delivery port. If the design is not final, an approximate volume and the main sections are enough for a budget price. We will tell you which lengths are easy to supply and which may need longer lead times.

Sources

• Lophira alata (Azobe) on Wikipedia
• Chlorocardium rodiei (Greenheart) on Wikipedia
• CIRAD Tropix for technical data.

Related guides

• Buy African Azobe wood
• Best wood for marine construction
• Best hardwood for decking
• Heavy construction and marine timber
• How to import timber from Africa

Frequently asked questions about azobe vs greenheart

Is Azobe stronger than Greenheart?

Azobe is usually harder and slightly denser. In bending and compression, both reach the top hardwood strength classes.

Which is better in salt water?

Greenheart has the stronger reputation against marine borers in warm salt water. In temperate and fresh water, Azobe performs very well.

Is Azobe the same as Ekki and Bongossi?

Yes. Azobe, Ekki and Bongossi are trade names for Lophira alata.

Which costs less?

Azobe is usually more economical and easier to source in volume.

Get a quote for Azobe

Send your section sizes, lengths and volumes through our quote form. We will reply with price per m³, lead time and the documents your project needs.