Tropical hardwood is a term used for all hardwood timber species grown around the Equator. These areas are characterised by lush green rainforests and harbour great biological diversity. In fact, the tropics are thought to contain 50% of the Earth’s plants and animals.
For external furniture, tropical hardwood usually refers to timber originating in the Congo basin and includes popular species such as Iroko, Ekki, Cumaru and Opepe.
It is impossible to obtain truly sustainable tropical hardwood. To find out why, continue reading, but if you came here for a quick answer you have it.
First, thanks for taking the time to read this blog. It can only be a force for good that we are researching about what timber is best to specify from a sustainability standpoint. This is in contrast with the more traditional approach of simply specifying a timber with the best combination of low cost and good properties.
Tropical hardwood is strong, durable and cost effective. Thanks to these factors there has always been strong underlying demand for tropical hardwood. However, especially in the western world tropical hardwood has experienced fluctuations in popularity. Before there was a widespread awareness of deforestation, it was massively popular. 10-20 years ago, its popularity dipped as people became aware of deforestation and decided tropical hardwoods were not an ethical choice. Then in the last decade there has been a resurgence in popularity thanks to the exploding awareness of sustainable forestry schemes such as FSC and PEFC.
These schemes essentially give tropical hardwood a ‘get out of jail free’ card.
Rarely is anything too good to be true. In the case of tropical hardwood, the perfect characteristics come at a considerable cost to the environment and sustainability.
There are two reasons why tropical hardwood is not sustainable that no timber certification can fix.
For the purposes of this blog, we are going to focus on timber coming from the Congo basin into the UK. However, the problem remains the same across the world, just the names change.
Shipping creates 17% of global C02 emissions. Therefore, shipping products over long distances is not compatible with sustainability. All tropical hardwood needs to be transported 8500 miles on a container ship powered by diesel, creating carbon emissions. There is not even the caveat that tropical hardwood is lightweight or small, like clothing or toys. In fact, one of the reasons tropical hardwoods are popular is that they are very dense and therefore, very strong. Of course, this does not improve the C02 emissions created during transport.
Most tropical hardwood comes from colossal trees that have been growing for over 150 years. The forests which contain these trees are known as old growth rainforest. This rainforest is the most valuable of all rainforest because it contains far more biodiversity than new growth forest such as fir plantations. In fact, plantations are also known as ‘green deserts’ because the plant and animal diversity they support is so small. Therefore, felling old growth rainforest is probably the most unsustainable form of logging around. FSC and PEFC certified tropical hardwood can come from old growth rainforest. It is difficult to imagine any scenario where felling these trees can be classed as ‘sustainable’.
Another sustainability problem created by felling old growth trees is that the growth period is approximately 3 times longer than the lifespan. A Iroko tree may take 150 years to fully grow, but the lifespan of a Iroko bench is around 50 years.
Nothing is wrong with FSC, PEFC and UKTR certification. In fact, these schemes fulfil a vital global need in protecting forests and the communities that rely on them. However, all we are trying to highlight is that just because a timber carries the FSC stamp, it does not magically become sustainable. There are other factors that make tropical hardwood unsustainable no matter how well managed the forests are.
It is important to remember that tropical hardwood typically comes from less well-developed countries. In these countries, the penalties for breaching environmental regulations are not so harshly implemented. We like to give timber certification bodies the benefit of the doubt that timber that carries their stamp does not flout environmental regulations. However, there are documented examples of this happening worldwide and it is not beyond the realms of imagination.
Also, some environmental groups brand timber certification schemes ‘fraudulent labelling’. Of course, the schemes disagree and trumpet the ‘sustainable practises’ they implement. The consensus is that although they are not ideal, they are much better at protecting forests than illegal logging.
We are not forestry management experts but we have done some research into which schemes are best. Read our blog here for full details, but FSC is a legitimate scheme with real benefits for the forests and communities. PEFC seems good but is dogged by claims of greenwashing and being a certification for logging created by the logging industry. EUTR/UKTR is a different model in that it is government regulation rather than an independent body. Therefore, all timber in the UK should adhere to UKTR regulation and suppliers and timber merchants should be able to provide full chain of custodies for sustainable timber tracking.
While there are no direct replacements for tropical hardwood in terms of characteristics, there are plenty of other options that are just as good, if not better, as long they are used on the right schemes and you are aware of common pitfalls.
In terms of sustainability, its far better to select a timber that is locally grown and/or has a short growth period.
Oak is a good alternative to tropical hardwood. The best Oak is grown here in the UK and is becoming increasingly cost effective. We have written a full blog about the suitability of Oak for external furniture here.
Douglas fir is another alternative. Although technically a softwood, it is almost as durable as tropical hardwood. Most tropical hardwood including Iroko is class 2 in the timber durability classification, whereas Douglas fir is class 3. This is an acceptable price to pay when you consider the environmental benefits of Douglas fir. Durability ratings are the main thing to consider when evaluating the strength and lifespan of a timber, not if it is a hardwood or softwood. Remember Balsa is technically a hardwood. Douglas fir also is UK grown, and is more cost effective then tropical hardwood and Oak.
In general, softwoods are more sustainable that hardwoods because they are typically faster growing and therefore can meet skyrocketing global demand.
When selecting a timber to use, if you have a choice do not choose tropical hardwood because of the sustainability problems associated with it.
However, we understand that for many projects, sometimes the only acceptable timber to use is tropical hardwood. The worst thing you can do is it to use a tropical hardwood that is not certified – the chances are it will have been illegally logged. A FSC stamp is preferable, because that is the most rigorous forest certification and will have a positive environmental impact on the environment. However, it cannot reduce the carbon transport emissions and probably will come from valuable old-growth forest.