What Does "A-Grade Heartwood Teak" Actually Mean?
If you've spent any time shopping for a garden bench, you'll have seen the word "teak" everywhere on flat-pack furniture at the local garden centre, on budget benches online, and on pieces built to outlast a generation. The wood in all three cases might technically be called teak. But not all teak is created equal, and the difference matters enormously if you want a bench that's still standing in your garden in 25 years.
Heartwood vs Sapwood - The Difference That Matters Most
A teak tree, like most hardwoods, produces two distinct types of timber as it grows:
Sapwood is the pale, outer layer of the trunk — living tissue that transports water and nutrients while the tree is growing. It's soft, porous, and contains almost none of teak's natural protective oils. Left outdoors, sapwood rots, warps, and attracts pests within a handful of years.
Heartwood is the dense, golden-brown timber at the centre of the trunk. As a teak tree matures, this inner wood becomes saturated with natural oils and silica — the very properties that make teak so prized for outdoor furniture in the first place. Heartwood is what gives a well-made teak bench its remarkable resistance to rot, insects, and weathering, without any need for chemical treatment.
The problem: sapwood and heartwood can end up in the same piece of furniture if a manufacturer is cutting corners, particularly with cheaper, mass-produced pieces that use the entire trunk to minimise waste and cost. A bench built partly from sapwood may look identical to one built entirely from heartwood — until a few winters in, when the sapwood sections begin to fail.
What "A-Grade" Signifies
"A-grade" is the industry term for teak that has been selected purely from mature heartwood, free of the sapwood, knots, and inconsistencies found in lower grades (often labelled B-grade or C-grade). A-grade teak:
- Comes from more mature trees, where the heartwood-to-sapwood ratio is highest
- Is hand-selected during milling to exclude sapwood and defects
- Has a denser grain and higher natural oil content, translating directly into weather resistance
- Requires no varnish, oil treatment, or chemical preservative to survive outdoors for decades
This is also why A-grade teak furniture costs more than lower grades — you're paying for timber that's been more selectively sourced, not simply for a label.
Why It Matters for a Garden Bench Specifically
Garden furniture faces a harder life than almost any other application of teak. Unlike a boat deck that's regularly maintained, or indoor furniture protected from the elements entirely, a garden bench sits outdoors year-round through frost, driving rain, and summer sun usually with minimal upkeep beyond an occasional clean.
This is precisely why the heartwood-only standard matters so much for a bench you intend to keep. A-grade heartwood teak, combined with proper joinery, is what allows a bench to develop that famous silvery-grey patina over time a sign of a slowly weathering surface oil layer rather than the cracking, splitting, and rot that shows up within a few short years in lower-grade timber.
How to Tell the Difference When You're Buying
Since sapwood and heartwood can look deceptively similar to an untrained eye, especially once furniture has been sanded and finished, the surest way to know what you're getting is to buy from a maker who is transparent about their sourcing and grading standards and ideally one who can speak to exactly where and how their teak is selected.
At Wealden Benches, every piece we build uses genuine A-grade heartwood teak, sourced in full compliance with UK Timber Regulations and UK FLEGT frameworks, and finished using traditional mortise and tenon joinery designed to give each bench a 25-year structural lifespan. It's a slower, more selective way to build furniture but it's the only way we know how to build something meant to last.
