Why local timber earns its place

Timber that grew within a few miles of your site carries a story as well as a set of practical advantages. Felled selectively by a woodland owner, sawn at a small mill down the lane and delivered on a flatbed rather than a container ship, it keeps money circulating in the regional economy and keeps haulage distances short. The carbon case is real, but state it honestly: sea freight is surprisingly efficient per tonne carried, so the largest savings appear when the alternative would be timber road-hauled a long distance. Where local timber wins decisively is in traceability, in the woods themselves, and in the craftspeople it keeps in work — sawyers and joiners who know exactly how the oak from a particular clay-heavy wood behaves.

Buying locally also connects a project to woodland management. A well-managed broadleaf wood needs regular thinning to let light in and to produce quality stems, and that thinning only pays if there is a market for the timber. Specifying local stock, even in modest quantities, helps keep that cycle turning.

Choosing species that suit the site and the use

Match the species to the exposure and the job. A sheltered courtyard, a south-facing screen and a footbridge over a stream are three different briefs, and treating them the same way is how good timber fails early.

• Oak — durable heartwood that works beautifully for frames, cladding and external joinery, but it moves noticeably and corrodes galvanised fixings, so specify stainless steel.
• Sweet chestnut — a strong coppice crop in southern Britain, durable enough for cladding, fencing and posts when the stock is heartwood-rich.
• Larch — good for cladding and external structures, though its sapwood needs protection and the heartwood is only moderately durable.
• Douglas fir — reliable for structural beams and decking; take the heartwood and keep it clear of the ground.
• Ash, sycamore and birch — lovely for interiors, furniture and linings, but not durable outdoors and best kept under cover.
• Scots pine — sound for internal joinery and, when properly treated, some external uses; its sapwood is not durable.

Whichever you choose, specify heartwood for exposed work. The pale sapwood band around every log is the soft, starch-rich part that insects and fungi attack first, and it is the reason two pieces of the "same" oak can perform completely differently in a west-facing wall.

Moisture content: the number that decides everything

Almost every failure blamed on local timber is really a moisture failure. Wood shrinks as it dries and swells as it takes on moisture, and it keeps changing until it reaches equilibrium with its surroundings. In the UK that means roughly 16–20% moisture content for sheltered external timber and 8–12% for heated interiors. Air-dried stock from a small mill typically sits around 15–20%, so it usually needs a final period of kilning or careful acclimatisation before it goes into a building.

Ask for a reading, not an assurance. A pin meter on a freshly planed face, taken across several boards rather than one, tells you far more than a promise that the timber is "well seasoned". If a supplier cannot tell you the moisture content, assume the worst and budget for re-seasoning. Air drying takes roughly a year per 25mm of thickness, so thick green beams bought cheaply in spring will not be ready by autumn.

Then design for movement. A 200mm-wide oak board can move several millimetres across its width between wet and dry seasons, so allow slotted fixings, oversized holes and open joints. Never trap a wide board hard against a rigid frame.

Durability, treatment and detailing for a wet climate

Timber performs best when water drains away quickly and air moves freely around it. A few habits prevent most problems:

• Keep timber at least 150mm clear of ground contact unless it is a naturally durable species or properly treated for that use.
• Form a 25mm ventilated cavity behind cladding, with insect mesh at top and bottom.
• Protect end grain with a chamfer or a drip, and never leave it facing upwards.
• Detail overhangs, gutters and flashing so that walls and posts stay dry in driving rain.
• Use stainless steel or appropriately specified hot-dip galvanised fixings — oak's tannins eat through some coatings.

Treatments have their place, particularly for sapwood-heavy softwoods, but a well-detailed durable hardwood will usually outlast a treated, badly weathered one. Prevention beats preservation.

Working with sawmills and local craftspeople

Visit the mill if you can, look at the stacks and the stickering, and ask about felling licences, restocking and any woodland certification. Ask how logs are sawn: through-and-through boards are wide and characterful but move more, while quarter-sawn stock is more stable and better for joinery. Ask about lead times too — good mills sell out, and a realistic schedule is worth more than a hopeful one.

A sawyer who understands your project can often cut to suit it, holding back the straight-grained stems for structural use and the knotty ones for cladding. That is a genuine design advantage that imported packs cannot offer.

Specifying with confidence

Write species, grade, durability expectation, moisture content range and fixing type into the specification, and ask for readings on delivery. Allow for movement in the details, keep water off the timber and air around it, and plan a simple maintenance cycle — a check and re-coat of any finish every few years. Get those basics right and locally grown timber becomes not a compromise but the obvious choice: a material with a short journey, a known origin and a long life in the landscape.