Grade A teak: what A, B and C tell you (and what they don't)

“Grade A teak” appears on plenty of price tags, but the letter tells you less than you’d think. What really determines teak quality is which part of the trunk is in it, how old the tree was, how well the wood was dried and how the piece is made. This page helps you judge that. What teak is and where it comes from is covered in teak wood.

Why “A, B, C” is not a quality mark

There is no official, generally accepted grading. The Indonesian producers say so themselves:

• Naramulya explicitly calls its A/B/C grading its own internal standard (Naramulya).
• Bali Teak Furniture warns that “grade A” at one workshop can be “grade B” at another, and calls the grades “banded descriptions, not guarantees” (Bali Teak Furniture).

And their definitions differ too:

Feature	Naramulya	Bali Teak Furniture
A	heartwood only, from large, mature trees from state plantations (Perhutani)	mature heartwood from the centre of the trunk
B	also heartwood only, but from private plantations	the outer part of the heartwood, with paler patches
C	smaller logs, full board including sapwood; mainly for indoors or dark finishes	sapwood and young wood; pale, more porous, “not weather-durable”

Sources: Naramulya, Bali Teak Furniture.

Both are traders with a commercial interest, but they agree on one thing: the difference is heartwood versus sapwood. So never just ask “is this grade A?”, but what the wood actually is.

Heartwood and sapwood: the real quality difference

A teak trunk has a darker core and a paler outer band. The Queensland Government describes the sapwood as pale yellow and clearly defined, and warns that untreated sapwood is susceptible to lyctid borers (Business Queensland). The durability teak is known for applies to the heartwood (Centrum Hout, Dutch).

That also explains questions about pale and untreated teak:

• If you see pale, yellowish strips, especially along edges or in a table top, that may be sapwood. For an indoor cabinet it’s mainly a matter of looks; Naramulya deliberately uses such wood for indoor collections (Naramulya). For outdoors or in a wet bathroom it’s a risk (Bali Teak Furniture). See also teak bathroom vanity.
• “Untreated” teak is often described in the trade with words that sound like a quality grade; the Dutch word blank, for example, is used by retailers such as Teakhuis for untreated, light-looking teak, not necessarily for sapwood (Teakhuis, Dutch). Ask what the seller means.
• Colour difference alone is no proof: Centrum Hout writes that heartwood darkens under light and that large colour differences usually disappear afterwards (Centrum Hout, Dutch).

Plantation teak: age matters

Almost all “Javanese” or “Indonesian” teak in the shops comes from plantations; what those origin names mean is covered in types of teak. The biggest quality difference within plantation teak is how old the tree was when it was felled.

A peer-reviewed study in Annals of Forest Science (2018) compared teak from Java under two types of management: state forest of Perhutani, felled after 40 to 60 years, and community plantations, felled after 7 to 10 years (Rizanti et al., 2018). The findings:

• According to earlier research the authors cite, teak of about 10 years consists of around 40% heartwood, teak of 40 years of around 80%.
• The young wood was lighter (472 against 664 kg/m³) and less resistant to wood-rotting fungi, because it contains less heartwood and fewer protective extractives. In swelling, bending strength and hardness, the researchers saw no great difference, according to their abstract.
• Fast-grown community teak “cannot be used as regular heartwood teak from Perhutani”, according to the authors.

The study is small (three trees per type), but the pattern fits with the Dutch timber information centre Centrum Hout, which puts teak from its natural range in durability class 1 and plantings outside the natural range in class 1 to 3 (Centrum Hout, Dutch).

What does that mean for you? A log from young trees gives narrower boards and more sapwood. For garden furniture, you want to know whether it’s heartwood from mature trees; for an indoor cabinet, young wood is less of a problem. Teak from old buildings is covered in reclaimed teak.

Drying: the invisible quality factor

Good teak that is badly dried will still crack. Bali Teak Furniture puts it briefly: grade tells you something about the wood, drying whether it’s ready to build with; they name kiln-drying to around 8–12% moisture content (Bali Teak Furniture), Naramulya gives the same range (Naramulya) and Gloster dries its teak to 12% (Gloster).

Dutch teak retailers point to the same thing: wood felled in Indonesia is very wet, and furniture that ends up in a heated living room insufficiently dried can crack, especially in winter (Teaktafels.nl, Dutch, Teakhuis, Dutch).

Construction and finish

• Solid or board? Solid wood moves with moisture and temperature; veneered board is more stable but harder to repair (Meijs Wonen, Dutch).
• Indoor or outdoor construction? An indoor table has glued wide boards without gaps; outdoor furniture has slats so the wood can move (Souren Meubels, Dutch, Gloster).
• Rough-sawn, brushed or untreated teak. Planed rough, brushed or left untreated: that’s a choice of finish, not a quality grade. Do check how it is finished: see indoor teak furniture.

Checklist: ask this before you buy

1. Heartwood or sapwood? How much pale wood is in it, and where?
2. What does the letter mean at this seller? Have them describe A/B/C in terms of characteristics.
3. Plantation, age, origin? Does the seller know what type of plantation the wood comes from?
4. How was it dried, and to what moisture content?
5. Solid, veneer or board? And is the construction meant for indoors or outdoors?
6. Certification or legality documents? Ask about them and ask to see the label; what the labels do and don’t mean is covered in FSC teak.
7. Can I see the raw wood or a sample?

We deliberately don’t give prices: we found no public, well-founded price ranges that are comparable per grade.

Care

However good the wood, care helps decide how it ages. Indoors, see indoor teak care; outdoors, how to treat outdoor teak furniture.