Botanical Name: Intsia bijuga
Other Names: Merbau, Ipil, Vesi, Taal
Source location: West Papua, Papua New Guinea, Indonesia
Stability: Class 2, Durable 15-25 years
Density: Approximately 830 kg/m3
Appearance: The heartwood is yellowish-brown, brown or dark red, red-brown, turning to a dark
red-brown with age. The wood is hard and heavy, the texture is moderately coarse but even
and the grain may be straight or interlocked and is often wavy. Sulphur-yellow and dark
coloured deposits are characteristic of the species and can be commonly seen in the vessel
Sustainability: Kwila is a rain forest timber and is not plantation grown. It takes an average of 80-
90 years of growth for Kwila to grow to commercial harvest size. Some supplies of Forrest
Stewardship Council certified stocks of kwila may be available but most imported stocks to
New Zealand are not certified.
Finishes: Kwila is a very dense hardwood and thus does not suit most timber finishes. Our
experience has shown that the finishes do not penetrate into the hardwood thus resulting in
poor adhesion and a tendency to ‘sheet’ off within a few months. Our recommendation is to
leave the timber unfinished allowing it to age naturally.
Leaching: Kwila is known to bleed a natural dye so care must be taken when placing near
existing surfaces i.e. concrete. To lessen the effects of the leaching, you can leave it out in
several downpours before installing on site. If staining has occurred, it can generally be
removed in the early stages by scrubbing with milk or lactic acid.