Responsibly sourced timber: what actually stands up, and what is greenwash
Written by Scott Jones, The Stair Guys, independent staircase measuring and sourcing specialists·Last updated
An FSC or PEFC label is the baseline (see what FSC or PEFC certified really means). It is what a maker does beyond the label that separates a real sourcing story from marketing. The test is simple: is the claim specific and can it be evidenced, or is it a vague word doing the work of a fact.
What actually stands up
These are the claims that hold weight because they can be shown, not just said:
- Chain of custody to a named source. "This oak comes from [named estate or mill], with the certificate number on file" is a real, checkable claim. It names something.
- Auditing your own sawmills, with records kept. Arguably the most honest beyond-certification claim, because it does not rely on carbon modelling. The maker can show what it buys and from where.
- Grown in Britain. A recognised scheme that guarantees British origin, which FSC and PEFC alone do not, and which counts as Category A evidence in UK public procurement.
- Reclaimed timber for non-structural parts. A genuine environmental choice for elements that are not load bearing. Not for treads or strings without an engineer regrading it (see below).
- Choosing abundant, non-threatened species. Worth checking both CITES and the IUCN Red List, not just one. CITES lists only part of the trade-threatened tree species, so "not CITES listed" does not by itself mean safe. Sapele is the one common stair timber that carries a real conservation caveat.
The traps: claims that sound green but do not hold
- "Slow grown, so stronger." For ring-porous hardwoods like oak and ash this is often the wrong way round: faster growth widens the dense latewood band, so faster-grown oak can be denser, not weaker. Ring width is not a reliable strength guide, so this claim does not stand up.
- "Local is always greener." British or European timber can cut transport miles, and transport is a real slice of a wood product's footprint, but distance is not the whole story. How the forest is managed and how the timber travels, by road, rail or sea, can matter more than how far.
- "Reclaimed is structurally equal to new." Reclaimed timber is excellent for character and carbon, but it is hard to strength-grade: unknown load history, metal, no simple regrade route. For anything load bearing on a stair it needs proper regrading and sign-off first.
- Any bare "eco", "green" or "sustainable" with nothing behind it. If it cannot be pinned to a specific, checkable fact, treat it as marketing.
Why a serious maker will show you the evidence
This is not only good manners, it is the law. In the UK, environmental claims are governed by consumer-protection rules, now the Digital Markets, Competition and Consumers Act, with the Competition and Markets Authority Green Claims Code as the guidance behind it. The principles are plain: claims must be truthful, clear, not leave out important information, make fair comparisons, consider the full lifecycle and be substantiated. A maker is accountable even for a claim it simply repeats from a supplier, and the CMA can now act directly and fine up to 300,000 pounds or 10 percent of global turnover, whichever is greater.
The upshot for a buyer is useful: a maker that is serious about sourcing can put a specific, evidenced answer in front of you, because it has to be able to. A maker that answers a sourcing question with a vague word is telling you something too. This is guidance, not legal advice, but it is why "show me" is a fair thing to ask.
SourceCMA Green Claims Code (guidance on environmental claims), gov.uk
Frequently asked
What does "responsibly sourced" timber actually mean?+
On its own, very little. It only counts when it is specific and can be evidenced, for example chain of custody to a named woodland, audited sawmills with records, Grown in Britain provenance, or reclaimed material used for non-structural parts. A bare "eco" or "sustainable" label with nothing behind it is marketing, not proof.
Is slow-grown timber stronger?+
Not reliably, and for oak and ash it is often the opposite. In ring-porous hardwoods faster growth widens the denser latewood band, so faster-grown oak can be denser rather than weaker. Ring width is not a dependable guide to strength, so "slow grown so stronger" does not stand up as a claim.
Can reclaimed timber be used for a staircase?+
For non-structural parts, yes, and it is a genuine environmental choice. For load-bearing parts like treads and strings it is not structurally equal to new timber without regrading, because its load history is unknown and it can hide metal. Anything structural needs proper regrading and sign-off first.
Sources
Primary sources we used and reconciled before publishing.
Related guides
- The label tells you the tree, not where it has beenA timber label like "oak" or "pine" tells you the species, not the journey. A lot of stair timber is shipped abroad for processing before it returns as "product", so here is what to ask about where your timber was grown and processed, and why it matters.
- Glass balustrades: why the joinery and fixings matter more than the glassOn a glass balustrade the glass is the easy part. What makes or breaks it is a dead-square, parallel frame (ideally tenoned and drawbored, not just screwed) and silicone bedding the glass so it is cushioned, held plumb and does not rattle.
- Which timber to choose for a staircaseThe best timber for a staircase depends on the part. Treads need a harder, wear-resistant wood like oak, ash or beech; handrails reward a timber that feels good in the hand; and paint-grade softwood is fine where it will be covered. There is no single best wood, and hardness is a guide, not a regulation.
- Metal spindles: cheaper than you think, and why simple lastsMetal spindles are more affordable than their reputation suggests, so they are worth a look on cost. But the more elaborate the design the faster it dates, so a simple, plain metal spindle tends to stay looking right far longer.
- Painting your stairs? What they should actually be made ofIf you are painting a staircase the material underneath still matters. Treads should be solid pine, never MDF. Risers are best solid, with plywood a sound second and MDF the one to avoid. Here is why paint hides the look but not how the material behaves.
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