The standard name for the timber of Dryobalanops spp. (Dipterocarpaceae). Vernacular names applied to this timber include kapur (Peninsular Malaysia, Sabah and Sarawak) with various epithets, keladan (Peninsular Malaysia) and kelansau (Sarawak). Major species include D. aromatica, D. beccarii, D. keithii, D. lanceolata, D. oblongifolia and D. rappa. The sapwood is yellowish brown and sharply defined from the heartwood, which is reddish brown.
The timber is a Medium Hardwood with a density of 580-820 kg/m3 air dry.
Standard graveyard test of untreated D. aromatica and D. oblongifolia specimens of dimension 51 mm x 51 mm x 610 mm had been conducted in the Forest Research Institute Malaysia (Jackson, 1965). From the studies conducted, the average service life of D. oblongifolia and D. aromatica were 1.9 and 6.0 years respectively. It can be seen that there is a remarkable difference in the natural durability of these two species and based on the weakest species, kapur is therefore classified as not durable. It is known that these two species are resistant to fungal attack, but are susceptible to termite attack.
The timber is not amenable to preservative treatment and it is classified as difficult to treat.
The timber of D. rappa is easy to work while the other species range from moderately easy to slightly difficult.
The timber is suitable for medium construction, posts, beams, joists, rafters, door and window frames and sills, fender supports, telegraphic and power transmission posts and cross arms, flooring, staircase (treads, angle blocks, rough brackets, bullnose, riser, balustrade, carriage, stringers, round end and winder), vehicle bodies (frame-work, floor boards and planking), ship and boat building (keels, keelsons and framework), pallets (heavy and permanent types), tool handles (impact), cooling tower (structural members), plywood, laboratory benches, column (light duty) and railway sleepers. In domestic flooring and internal fittings where finished appearance is important, care should be taken in fixing because of a tendency to develop an unsightly black stain in contact with iron nails, screws or other fittings.