The Standard Malaysian Name for the timber of Koompassia malaccensis (Leguminosae). Vernacular names applied include impas (Sabah) and menggris (Sarawak). This is a monospecific timber. The sapwood is white or pale yellow and is sharply defined from the heartwood, which is pinkish when fresh and darkens to bright orange-red or deep brown.
Also known as Kempas (Brunei); Hampas, Impas, Kempas, Keranji, Mengeris, Mengris, Pah and Upil (Indonesia); Koompassia (Papua New Guinea); and Makupa, Sifai and Tong-bueng (Thailand).
DENSITY
The timber is a Medium Hardwood with a density of 770-1,120 kg/m3 air dry. It was reported that the material from Sabah and Sarawak is much denser than the material from Peninsular Malaysia.
NATURAL DURABILITY
Based on the standard graveyard test of untreated specimens of dimension 51 mm x 51 mm x 610 mm, the wood is classified as moderately durable under the Malaysian condition. In a test conducted at the Forest Research Institute Malaysia (FRIM), the average service life for 161 untreated specimens was 2.5 years. The sapwood is very susceptible to both powder-post beetles and fungi attacks, while the heartwood is readily destroyed by termites. Kempas treated with the appropriate wood preservatives is very durable even under exposed condition. In an experiment, 40 test sticks (64 mm x 64 mm x 760 mm) with an average absorption of 224 kg/m3 (14 lb/ft3) of creosote were buried for the durability test. 25% of the specimens were destroyed after 35 years.
PRESERVATIVE TREATMENT
The timber is amenable to preservative treatment and it is classified as easy to treat.
TEXTURE
Texture is rather coarse but even except in areas where included phloem occurs. Grain is interlocked, often very interlocked.
COMMON USES
Heavy structural use, Mouldings, Cladding, Decking and for House Roofing (Roofing Timber).