What to expect when choosing natural timber for your post and beam timber framed building
Natural Timber Characteristics
When choosing solid timber, please remember that it’s a natural organic material and that many of its prized features derive from the fact that it ‘moves’ over time and with the climate. From the moment that it is felled and milled timber shrinks, twists and ‘shakes’(cracks) as moisture content changes. It may also exhibit knots and ‘wany’ edges where bark has been removed and show tannin and sap marks on the surface.
These features also influence the way that it is used, requiring traditional craft skills to work joints and relationships between timbers during fabrication. It is all of these things that combine together to give ‘real’ solid timber structures their ageless beauty, charm and exceptional value.
Many of these features may already be present on delivery of your building or appear shortly afterwards. As explained above these are normal and to be expected though we are careful to check that all timber leaving our factory falls within well-defined and industry accepted limits for these characteristics.
Because each piece of timber is different, they react differently, leading to some being more prone to splitting and cracking, than others. The following image shows 3 beams, all crafted at the same time, but as you can see, the beam on the right is showing greater signs of splitting than the other 2.
Whilst splits and cracks can appear alarming, It is really only a case of aesthetics, they have no effect on the structural integrity.
Storing and Handling Natural Timber on Site
When needing to store timbers on site prior to installation it should be kept off the ground, well spaced, and protected from the weather (sun, rain, snow) to minimise the chance of any ‘movement’ that might interfere with assembly.
Also when handling and erecting timber please remember that it is relatively easy to damage the edge.
An example of green oak cladding that had not been adequately stored and protected onsite during a hot spell
Leaching out of sap and tannins from the timber can discolour any surface over which it is laid.
Some timbers, like oak, are susceptible to contact with iron and steel. Forklift prongs, for example, can leave a ‘blue black’ mark on green oak or other timber, although this can easily be removed by sanding or sand blasting.
If Natural Timber Characteristics are not for you
If any of the above concerns you then talk to us about using our ‘Glulam’ posts and beam structures as an alternative to solid timber.
Glulam is an engineered timber made from short, regularised softwood ‘lamelas’, from which knots and other naturally occurring blemishes have mainly been removed. These ‘lamelas’ are then glued together to make incredibly strong components which are less prone to ‘movement’.
They can be made in very large sections and, weight for weight, are stronger than steel and can be stained to take on the appearance of whatever natural timber you prefer.