In short: Azobe is a very hard and heavy wood from Africa. It is also called Ekki or Bongossi. Its botanical name is Lophira alata. Under the EN 350 standard, its heartwood is in durability class 1, the highest class. Correctly installed, Azobe structures commonly last 25 to 40 years or more, even in ground or fresh-water contact, without any chemical treatment. That is why Azobe is the first choice in the Netherlands for bank revetments, sheet pile walls, piles and quay walls.
What is Azobe?
Azobe is a hardwood from the rainforest. It grows in West and Central Africa, in countries such as Cameroon, Gabon and Nigeria. In English it is often sold as Ekki. In Germany it is known as Bongossi. It is always the same type of wood.
Freshly sawn, Azobe is dark red to brown. Sun and rain turn it silver-grey over time. One cubic metre weighs about 1,000 to 1,100 kg. So Azobe is heavier than water. It sinks. For work in water, that is a plus.
Douglas fir and larch do not last nearly as long. They are not suited for use in water. Azobe is different. It can stand in water or soil for a long time. Few types of wood can do that.
Properties and durability class
Property | Azobe (Ekki) |
|---|---|
Botanical name | Lophira alata |
Origin | West and Central Africa |
Durability class (EN 350) | 1 – very durable |
Use class (EN 335) | Suitable for class 4 (contact with soil and fresh water) |
Service life in ground and water | 25–40 years or more |
Density | approx. 1,000–1,100 kg/m³ (heavier than water) |
Colour | dark reddish brown, weathers to silver-grey |
Chemical treatment | not needed |
Supplied by Jan Sok | fine-sawn; tongue-and-groove profile 30–50 mm, lengths 2–5 m |
What does durability class 1 mean?
The EN 350 standard sorts wood into five classes. They show how well a wood resists fungi. Class 1 means very durable. It is the best class. Azobe gets there without any treatment. So no chemicals end up in the water. That is good for ponds, ditches and rivers.
What is Azobe used for?
Azobe fits wherever wood stands in water or soil for a long time. It also carries heavy loads. Common uses are:
- Bank revetment: It protects the banks of ponds, ditches and streams. Read more in What is a bank revetment? and Buying revetment timber.
- Sheet pile wall: This is a heavier wall. It holds back water, for example at quays. See What is a sheet pile wall?
- Piles in water: They support bridges, jetties and other structures.
- Quay walls: They protect the shore in harbours and along canals.
- Bridges, jetties and moorings: Here you need wood that can take a lot.
- Sleepers and beams: for example for rail tracks or foundations in the ground.
For bank revetments, we supply complete packages through Revetment systems. You will find all our hardwood, including Azobe, in the Hardwood shop.
Azobe compared with other woods
Wood | Durability (EN 350) | Long-term in water? | Treatment needed? |
|---|---|---|---|
Azobe (Ekki) | 1 | Yes, 25–40 years or more | No |
Larch | 3–4 | No | Not suitable for ground contact |
Douglas fir | 3 | No | 10–15 years above ground, 5–10 years or less in the ground |
Pine, pressure-treated | improved by treatment | Limited | Yes (impregnation) |
Conclusion: Will the wood stand in water all the time? Then Azobe is the better choice. It lasts much longer than treated softwood. It also carries more. The price is higher. But you will need to replace it far less often.
Pros and cons of Azobe
Pros:
- It can stand in water and soil for a long time.
- Correctly installed, it commonly lasts 25 to 40 years or more in water.
- It needs no chemicals.
- It is very hard and strong. It barely warps.
- It stands up well to currents and waves.
Cons:
- It is heavy and hard. That makes it harder to work with.
- Small cracks can form as it dries.
- It can splinter. So it is less suited for bare feet.
- Left untreated, it turns grey. This only affects the look.
- It costs more than softwood.
Tips for working with Azobe
- Pre-drill: Always drill first before you screw or nail. Otherwise the wood may split.
- Tools: Use carbide saw blades and drill bits. Normal tools go blunt fast.
- Screws and nails: Use stainless or galvanised steel. That way you get no rust and no stains.
- Transport: One cubic metre weighs about a tonne. Plan delivery and fitting with care. We are happy to advise you.
Maintenance
In water, Azobe needs almost no care. That is exactly why people choose it for bank revetments and sheet pile walls. Above water, the wood turns grey over time. Want to keep the colour? Then clean the wood once a year. After that, apply a suitable hardwood oil.
Origin and sustainability
Azobe comes from tropical forests. So look for clear proof of where it comes from. Houthandel Jan Sok only supplies Azobe with proof of origin. The wood also lasts a very long time. So you rarely need to replace it. Over the years, that saves a lot of material.
Azobe compared with other hardwood species
Compared with Okan or Tali, Azobe is considerably heavier and denser, which explains its exceptional resistance in permanent water contact. That density also makes processing more demanding: pre-drilling is necessary, and tools wear faster.
Frequently asked questions
What exactly is Azobe?
Azobe is hardwood from Africa in class 1. It is very hard and heavy. It handles permanent ground and fresh-water contact, and correctly installed structures commonly last 25 to 40 years or more.
What applications is Azobe used for?
Mainly for sheeting, dam walls, piles in water and quay walls. Those are works that stand in water or ground for good.
How long does Azobe last in water?
Correctly installed, Azobe commonly lasts 25 to 40 years or more in water. Its heartwood is durability class 1, the highest class under EN 350.
Does Azobe need treatment?
No. Azobe lasts on its own and needs no extra treatment. Outdoor wood with no oil greys in a slow even way. That change is only the look and does not harm the build.