Iroko

Material Type:
Hardwood

Also Called:
Kambala, Mokongo, Lusanga, Moreira, Tule, Rokko, Intule, Odum,

Durability Notes:
Although the heartwood of Iroko has a high natural resistance to decay, it can be vulnerable to attack from dry-wood insects. The sapwood can be attacked by the powder-beetle. Resistant to preservative treatment, which is not, however, normally required. Good, naturally oily hardwood, ideal for areas of high exposure. Needs to be de-oiled before decoration with methylated spirit

Seasoning:
The drying and seasoning of Iroko is dependant on a number of factors; the speed in which it is processed after felling and logging, the method of drying and the specific kilns or location (if air dried). Generally the care taken by those processing the wood will have an impact on its drying and seasoning. As an overview; Iroko - The wood dries well and fairly quickly, with little impact on the grade and quality of the wood. There can be slight checking and distortion. The wood is expected to move very little in service. Please note that all wood is liable to move when in service plus there can be dimensional change. The extent of this will depend on; the stability of the species itself, the conditions it is exposed to, the coating, decoration and protection. You will find more information about the suitability of this wood, for any proposed application, by using our interactive system and the filters shown.

Properties:
Iroko has medium density and a tolerable steam-bending rating. It works adequately with hand tools. Tolerable to severe blunting effect on cutting edges. Planing, turning and moulding - the results are generally good. Interlocked grain can cause tearing and the mineral deposits can blunt cutters rapidly. It glues, nails and stains well and screws, varnishes and paints adequately. Naturally oily, Iroko, needs to be de-oiled with methylated spirit before painting. Iroko can be brought to a high gloss finish after filling.

Typical Uses:
Furniture, interiors and exterior joinery, carving, mouldings; boatbuilding, shipbuilding, piles and other marine work; laboratory benches, factory and parquet flooring. Also plywood, wall panelling and decorative veneer.

Spiritual Properties:
The tree is feared in some cultures where it originates for example - Yoruba people believe that the tree is inhabited by a spirit and any man who cuts down any Iroko tree causes misfortune on himself and all of his family.

Moisture Content:
14-18% KD

Possible Health Risks:
Dermatitis, furunculosis, asthma, nettle rash. Dust is fine and can cause respiratory problems.

Sustainability:
Considered lower risk/near threatened by the IUCN Red List of Threatened Species (this was last assessed in 1998 and considerable changes in awareness and more stringent forestry controls may have had an impact and the results of the latest assessment are due soon) for more information and latest updates please visit http://www.iucnredlist.org and type in the botanical name of the species into the search box. It should also be noted that one unintentional shortcoming of the Red List is that it only considers the risk of extinction; broader issues dealing with habitat destruction or deforestation are not considered. Also, it does not necessarily take into account the maturity of the trees (i.e., centuries-old trees are cut down, and subsequently replanted with saplings) Therefore we hope that further assessments will consider this long term commitment to re-growth.The reason Iroko is at risk is due to a number of factors; suffers from heavy exploitation. East Africa was once a major source of the timber, which was used as a teak substitute until supplies, became short. West Africa continues to export large quantities of it. Some sub-populations suffer from gall attacks, especially in plantations, and its seed loses viability quickly.

Wood Worker's Thoughts:
Hard to work due to density and tight grain. Cross graining issues can occur in finishing and moves during cutting. It is a naturally oily timber which enhances it's durability and performance when exposed. If choosing to paint or stain de-oiling the timber is recommended with methylated spirit or similar.

Commonly asked questions about Iroko Wood

Is Iroko a hardwood or a softwood? Iroko is a hardwood. It is the same for; is Iroko hardwood or softwood? - Iroko is a hardwood.

Most groups/families of species share the same characteristics but this normally relates to their life as plants. Individual species do not always share the same characteristics as their relatives, in terms of the wood. Many factors influence how we use the wood and what we use it for, including where it grows, how it is forested, how it seasons/dries, etc. The answers to the following common questions, therefore relate to this particular species/wood and not the Iroko family as a whole. Even more specific – our answers relate to the wood (as we know it) in its form as a useable resource.

What colour is Iroko? Iroko can be described as yellow/brown

Is Iroko good for outdoor use? or is Iroko good for exterior use? Iroko is most suited for exterior/external use. Iroko can be used as an exterior/external timber (without treatment).

Whether the wood is naturally durable or not we would still recommend that it is decorated and/or coated with a suitable product to provide protection and/or maintain its appearance. This even applies when using the wood internally as, even subtle, changes in temperature or humidity will affect the wood. This will depend on the application/purpose of the wood and the user’s desired appearance. We also recommend that a recoating, care and maintenance programme is adhered to, for the life of an exterior wood. Wood cannot rot if it is kept dry – coatings and decoration can provide this protection. All of that said there are many durable timbers that are often left to weather naturally and will last for many years untreated/coated – movement and visual changes will occur but this is sometimes the desired effect. All wood is hygroscopic (it 'wants' to be in tune with its environment) it will therefore take on water from moisture in the air (or when directly exposed to or submerged in water) and ‘release it’ when dry or exposed to heat. This, inevitably, results in movement and dimensional change. For more about moisture in wood please click here - Moisture in wood