Decode timber merchant jargon: Your cheat sheet
It can feel overwhelming when you visit a timber merchant for the first time. Because the industry has its jargon, so when you know how to describe something in terms of what they understand you are more likely to get a clear communication and can order with confidence.
A Brief Guide to Common Timber Merchant Lingo
Nominal vs. Actual Size
Nominal size is the rough-cut dimensions, not the planed and finished (P&F) sizes we are discussing in this article. Size is what you get (which in reality is smaller) A so-called “2×4” may measure 1.5 by 3.5 inches (38 mm x 89 mm), or much smaller than the nominal dimensions due to planing and shrinkage. Be specific when you mention measurements.
PSE and PAR
PSE (Planed Square Edge) and PAR (Planed All Round) refers to the finish of timber. PSE timber has 2 smooth sides and PAR is planed on all four of its faces. Rough-Sawn Timber: This has never been planed and still boasts its coarse, unfinished look.
Kiln-dried: Drying wood in an oven where higher temperatures can be achieved, quickly and more evenly reducing moisture content to 12-18%. Naturally Dried Timber: Air dried timber takes longer to dry on its own, and has a higher moisture content. Like kiln-dried wood, it’s more stable and ideal for indoor projects. For Timber Merchants Winchester, contact https://www.timbco.co.uk/timber-merchants-winchester/
Treated Timber
Pressure treated lumber is wood that has been infused with preservatives to protect the wood from rot, decay and insects. Great for outdoor use and in contact with the ground. The treatment class (C16, C24…) determines the protective level and load-bearing capacity.
Whatever the names, this classification describes tree type rather than wood hardness. Deciduous trees produce hardwoods such as oak and ash, while softwoods come from conifers including pine and spruce. In fact, some softwoods are “harder” than many hardwoods.
Grading
Quality is also reflected in timber grades, which are determined by the knots, grain and defects. The more imperfections there are, the lower grade they have and can be useful for places where it will not show up. The basic grades are Select, Prime and Construction grade.
FSC Certified
FSC-certified means that the wood used to make this product comes from forests that are responsibly managed and meet environmental and social requirements.
Knowing these terms gives you clarity to ask the correct questions, compare quotes correctly and strive for your bespoke requirements in choice of timber.
