What is kempas?
The Wood Guide · The wood register
Tropical hardwood · referenceKempas
Warm orange to reddish brown, very hard and surprisingly strong. Popular for indoor floors and stairs — and with one limitation you need to know about.
- Koompassia malaccensis
- 40 to 60 m tall
- Excellent indoors, treated outdoors
Kempas
Warm orange to reddish brown, very hard and surprisingly strong. Popular for indoor floors and stairs — and with one limitation you need to know about.
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Kempas in brief
The wood of Koompassia malaccensis, an imposing broadleaf tree from the tropical rainforests of Malaysia, Indonesia and Thailand.
The tree reaches forty to sixty metres, with a straight trunk one to one and a half metres in diameter. The wood it yields is warm orange to reddish brown, with a high density and a strength that makes it suitable for heavily loaded indoor uses.
Indoors, kempas is excellent: hard-wearing enough for stairs and heavily used floors, with a warm colour that sets it apart from the browner tropical species. Outdoors it is a different story — there it needs a protective treatment.
In Southeast Asia, Koompassia trees are known as nesting trees for giant honey bees. Local honey hunters climb them, and in parts of Malaysia the trees are therefore spared during felling — the wood is worth less than the honey the tree produces every year.
- Botanical
- Koompassia malaccensis
- Origin
- Malaysia, Indonesia, Thailand
- Height
- 40 to 60 metres
- Trunk diameter
- 1 to 1.5 metres
- Colour
- warm orange to reddish brown
- Strength in
- hardness and wear resistance
To be fair: kempas is not inherently durable outdoors and needs treatment. It also reacts strongly with iron — black stains around every ordinary screw — and it moves more than many other tropical hardwoods. For outdoor work there are better choices.
What characterises kempas
High density
Heavy and hard, with the wear resistance a staircase or heavily used floor demands.
Warm colour
Orange to reddish brown, distinctly warmer than most tropical flooring species.
High strength
Good bending and compressive strength, also suitable for structural indoor uses.
Reacts with iron
Tannins cause black stains around ordinary steel. Stainless steel is a must.
What kempas is used for
| Use | Suitable? | What to look for |
|---|---|---|
| Indoor floors | Excellent | The main use; very hard-wearing |
| Stairs | Excellent | Hard enough for intensive use |
| Indoor structures | Good | High strength |
| Outdoor work | Limited | Needs treatment; other species are more suitable |
| Furniture | Good | Heavy; pre-drilling is a must |
| Ground contact | Not recommended | Choose azobé, bilinga or robinia |
Frequently asked questions about kempas
Can kempas be used outdoors?
Why are black stains appearing around my screws?
Because of the reaction between the tannins in kempas and the iron in ordinary steel. Use stainless steel fixings; existing stains are permanent.
What is kempas best suited for?
Indoor floors and stairs. It is hard, hard-wearing and warm in colour — exactly what a heavily used floor demands.
How big does a kempas tree grow?
Forty to sixty metres, with a straight trunk one to one and a half metres in diameter.
Kempas in perspective
An excellent indoor wood, but not the first choice outdoors.
Have a question about your project? Just ask — we're happy to help.
Photo via Wikimedia Commons: Koompassia malaccensis — Vitanes, CC BY-SA 4.0