What Is Apitong Wood? Keruing Hardness, Rot Rating and Uses

Apitong, sold interchangeably as keruing, is a dense Southeast Asian hardwood (genus Dipterocarpus) that measures 1,390 lbf on the Janka scale, but it is only moderately resistant to rot, not the near-bulletproof outdoor wood many sellers claim. This guide covers apitong’s real strength numbers against oak, teak and pine, how it moves, how to work it safely, and what to check before you buy.

What Is Apitong Wood?

Apitong is a commercial hardwood cut from trees in the Dipterocarpus genus, which belongs to the Dipterocarpaceae family and grows across Southeast Asia. In the lumber trade the same material is also called keruing, and the Wood Database notes it is sometimes marketed as “Asian mahogany” as well.

Two points shape everything else in this article. First, apitong is a group of related species, not one tree, so a board from one mill can differ in weight and color from a board from another. Second, it is a utility timber: its reputation was built on truck beds, trailer decks and flooring rather than fine furniture. Heartwood runs from light yellowish brown to a darker reddish brown, with grain that is generally straight to slightly interlocked and a medium to coarse texture.

Because its trade names overlap, searchers also ask whether the wood is safe to handle. Our separate guide on whether apitong wood is toxic covers dust limits and resin in detail, so this page keeps to identification, properties and buying.

Apitong Properties at a Glance

These figures come from the Wood Database entry for keruing (Dipterocarpus spp.). Treat them as typical averages, since individual boards vary.

Property	Keruing (apitong) value
Janka hardness	1,390 lbf (6,170 N)
Density	46 lbs/ft3 (745 kg/m3)
Specific gravity	0.59 basic, 0.74 at 12% moisture content
Modulus of rupture	16,710 lbf/in2 (115.2 MPa)
Modulus of elasticity	2,293,000 lbf/in2 (15.81 GPa)
Crushing strength	8,900 lbf/in2 (61.4 MPa)
Shrinkage (radial / tangential / volumetric)	5.5% / 10.8% / 16.3%
Decay and insect resistance	Moderately durable; moderate to poor insect resistance

Source: The Wood Database, Keruing. The earlier version of this page described apitong density as about 700 kg/m3; the published figure is 745 kg/m3.

Apitong vs Oak, Teak and Pine: The Numbers Side by Side

Most pages on apitong say it is “as strong as oak” without showing the data. Here it is, using Wood Database figures for each species so the comparison is like for like.

Wood	Janka (lbf)	Density (kg/m3)	Modulus of rupture (lbf/in2)	Volumetric shrinkage	Decay rating
Apitong / keruing	1,390	745	16,710	16.3%	Moderately durable
White oak	1,350	755	14,830	16.3%	Very durable
Red oak	1,220	700	14,380	13.7%	Non-durable to perishable
Teak	1,070	655	14,080	7.2%	Very durable
Longleaf pine	870	650	14,500	12.2%	Moderately resistant

Three things stand out. Apitong has the highest bending strength of the five, about 13% above white oak (16,710 vs 14,830 lbf/in2), which is why it carries heavy point loads on trailer decks so well. It is also tied with white oak for the largest volumetric shrinkage in the table, 16.3%, more than double teak’s 7.2%. And on decay it sits below both white oak and teak, a gap that most sellers skip over.

Is Apitong Really Rot Resistant? Correcting a Common Claim

Many product pages, and an earlier version of this article, say apitong naturally resists rot and insects. The measured rating is more modest. The Wood Database calls keruing “moderately durable” with moderate to poor insect resistance, while white oak and teak are both rated very durable. Apitong beats red oak, which is rated non-durable to perishable, but it is not a wood you can leave bare in constant moisture and forget.

In practice that means a penetrating oil or sealer is part of owning it outdoors. A film finish that cracks under cargo traffic lets water in and hides the damage, so oil-based penetrating treatments are the usual answer; our guide to what to treat a wood trailer deck with compares the main options and re-coat intervals. Keep end grain sealed, because that is where moisture enters fastest.

Shrinkage, Cupping and Board Movement

Apitong’s tangential shrinkage (10.8%) is almost twice its radial shrinkage (5.5%), a ratio of about 2 to 1. Flat-sawn boards therefore try to cup as they dry or as humidity changes, while quarter-sawn boards stay flatter. The percentages are measured from green to oven-dry, so a board in service moves by only a fraction of them, but the ratio still tells you which direction it will move.

• Let boards acclimate in the space where they will be used for several days before fastening.
• Leave small expansion gaps between deck boards rather than butting them tight.
• Fasten with enough screws or nails per board to hold the face flat; wide flat-sawn boards need the most restraint.
• Seal all six faces, including cut ends, so moisture changes happen evenly.

These are general good-practice steps rather than manufacturer specifications, so follow your supplier’s installation sheet where one exists.

Common Uses for Apitong

The Wood Database lists furniture, flooring, trailer decks and utility lumber as the main uses. The strong, stiff, affordable combination is why trailer and truck decking is the best-known application. If you are planning that kind of project, see our guide on how to build a wood bed for a truck for wood choices, costs and steps.

• Trailer and truck decking: dense and stiff under concentrated loads.
• Flooring: a hardness of 1,390 lbf resists dents better than red oak at 1,220 lbf.
• Utility lumber: framing, bracing and platforms where cost matters more than looks.
• Furniture: workable for rugged pieces, though coarse texture and resin make fine finishing harder.

For comparison with a famous hardwood, see how genuine and African mahogany compare on Janka hardness.

Working With Apitong: Blades, Resin and Dust

The Wood Database describes keruing as generally easy to work with hand or machine tools, with two caveats: silica in the wood dulls cutters, and resin can exude. It also reports that keruing has been reported to cause skin irritation. Those facts drive a few sensible habits.

• Use sharp carbide-tipped blades and bits, and expect to sharpen or replace them sooner than with oak (general shop practice, not a tested figure).
• Wipe off resin before it hardens, and keep it away from your blade teeth.
• Wear gloves and long sleeves if your skin reacts to tropical hardwoods.
• Wear a P100-rated respirator and use dust collection when cutting or sanding; hardwood dust is a respiratory hazard regardless of species.

Our apitong toxicity guide goes deeper on exposure limits, while the respirator in the box above is the baseline protection for dusty jobs.

Is Apitong Sustainable? What the Evidence Says

Older versions of this page said apitong comes from sustainably managed forests. That is too optimistic. The Wood Database reports that multiple Dipterocarpus species are listed as critically endangered, with population reductions of more than 80%. Because “apitong” and “keruing” cover several species, a sustainability label on the trade name alone tells you little.

If this matters to your project, ask the supplier for the species and country of origin and any chain-of-custody certificate (such as FSC) for the specific lot. We cannot confirm certification for any particular board, so treat any sustainability claim as unverified until you see documentation.

Buying Apitong: Availability and What to Ask

The Wood Database says keruing is not commonly imported to North America as a general hardwood and that prices should be moderate. In practice it is most often found through trailer-decking suppliers and some specialty lumber yards, usually as shiplap or rough boards rather than furniture-grade stock. Prices vary by supplier, thickness and shipping, so quote two or three sellers before ordering.

• Which species or species group is it, and where was it harvested?
• Is it kiln-dried, and what is the moisture content at shipping?
• Is it sold shiplap, tongue-and-groove or plain boards, and in what thickness and length?
• Is any preservative or finish already applied?

Frequently Asked Questions About Apitong Wood

Is apitong the same as keruing?

Yes, for practical purposes. Apitong and keruing are two trade names for lumber from the Dipterocarpus genus of Southeast Asian trees, so one board can be sold under either name. Because the lumber comes from several species, density and hardness vary from lot to lot.

How hard is apitong wood?

The Wood Database lists keruing at 1,390 lbf on the Janka scale. That is harder than red oak (1,220 lbf) and close to white oak (1,350 lbf), so it resists dents well but is tough on saw blades and drill bits.

Is apitong wood rot resistant?

Only moderately. The Wood Database rates keruing as moderately durable with moderate to poor insect resistance, which is a step below white oak or teak. Outdoors it needs a penetrating sealer and periodic re-coating to last.

Is apitong wood toxic?

A finished, sealed apitong board is not considered a toxic material, but the Wood Database notes that keruing has been reported to cause skin irritation, and the dust and resin from cutting are the real concern. Wear a P100 respirator and gloves when machining it.

Is apitong good for trailer decks?

It is a long-standing choice for trailer and truck decking because it is dense, stiff and relatively affordable, with a modulus of rupture of 16,710 lbf/in2. Plan to seal the boards, since its rot resistance is only moderate.

Bottom Line

Apitong earns its place where a stiff, hard, affordable board is needed: trailer decks, utility flooring and rugged platforms. Its Janka rating of 1,390 lbf and modulus of rupture of 16,710 lbf/in2 are genuinely strong, but its decay resistance is only moderate, its shrinkage is high, and its dust and resin call for a respirator and gloves. Seal it, give it room to move, and verify the species and sourcing before you pay.