STRUCTURAL OAK CURVES

In heavy structural timber framing the bracing is often done with what we call ‘grown’ curves.

structural oak curves for authentic brace making in heritage restoration

These curves are usually limbs of a trees, usually Oaks, which have grown with natural curves and therefore, due to the fibrous structures within the wood, have a natural tension and compression within them – it’s nature’s version of pre-loading.

This is the inherent property that makes the curved tree limbs ideal as timber frame braces, because none of the fibres have been cut in the length, they stay intact throughout the length, bound to each other and maintaining mechanical strength.

 

The alternative; braces from cut curves

As curves don’t exactly grow to order we can supply a complete fresh sawn through & through board that has been cut to achieve the requirements and then the actual shaping is done by the framer.  A cut curve is a brace that has been cut and shaped from a blank section of regular, straight grown structural timber, usually Oak.

These may be more suitable for use on single storey buildings where bracing has less loading or on new builds which don’t require such authentic attention to detail. They’re a great alternative to ‘grown’ curves. They’re cut to order as part of any fresh sawn Oak cutting list, and are priced in the samw way.

When would you choose a natural curve over a cut curve?

A skilled carpenter-framer might select natural grown curves for bracing over cut ones where a traditional frame is being restored and historical integrity needs to be maintained. Perhaps also if the frame is being built as a residence, perhaps extra strength is required, or if a barn structure requires authentic timber replication then these fit the bill.

We should say that ,in our experience, the timber framers specifying curved braces are skilled craftsmen and know how to work the timber to get the best results, whichever the brace they use.

Ordering curves for braces

Whether grown or cut, the curves are usually supplied as waney edge, through and through cut, to the specified brace thickness. We periodically have stock of Oak curves, kept in our beam yard for selection alongside the rest of our seasoned structural stock. Due to scarcity, we don’t always have them available but they can also be sourced from normal air dried waney edge boards, of which we keep 80mm, 100mm and 120mm thick in Oak.

Our structural stock is primarily for restoration and renovation work, however it is excellent for new build frames and whilst will already have begun to dry and show plits and cracks that also means it is already stabilising, hardening and toughening. It’s also easier to achieve a smooth, clean surface from planing,

Our French sourced structural timber (Oak) is certified PEFC.

Our British sourced structural timber (Douglas Fir, Chestnut) is certified Grown in Britain .

Chain of custody certification is provided with your order.

Do you need  TRADA certified Visual Strength Grading BS 5756 for Oak as an additional service? See the pdf below for more information.

Use the links in our menu to explore our STOCK or to GET A QUOTE

MORE INFO

Whilst we don’t have in-house curve shaping facilities we’d be glad to put you in touch with someone who can help – have a look through our Woodworker directory to find a skilled carpenter-framer you like the look of.

Find out more about our timber certification Grown in Britain & PEFC

 

STRUCTURAL OAK CURVES Gallery