Moisture content in timbers can be problematic for a timber framer or anybody building with beams and timbers.   A living tree contains large amounts of standing water, and once cut, a timber can take years to dry.  As moisture enters and exits the wood the timber is prone to significant movement.  The timber industry does not invest the time and capital in letting timbers season before putting them on the market.  Most timbers today are sold as “green” – they contain significant moisture and are prone to movement as the moisture leaves the timber and the wood reaches an equilibrium with the relative humidity of the surrounding air.  In regards to Douglas fir timbers, they are considered “dry” if their moisture content is below 19%.  It is widely known that conventional kilns are ineffective at drying large timbers because they heat the outside of the wood but not the inner core.

In recent years, new technology has been developed to allow for more rapid drying of timbers.  This technology uses what is known as a Radio Frequency Vacuum (RF-V) to dry the timbers.  Just as with a standard microwave oven the RF-V kiln uses microwaves to excite the water molecules and and it then draw them out using the vacuum.  While this technology can produce the desired moisture content reading, it is unclear if it has any overall effect on the future stability of the wood.

It has been our experience that AltruWood Naturally Dry Douglas fir timbers are superior in performance to RF-V kiln dried timbers.

There are a few reasons for this.  For starters, the drying process begins before the tree is cut while it is still standing vertically – this is where the lumber gets its name.   The tree then begins to release its moisture the same way it acquired it – through the root system in the ground.  An AltruWood Naturally Dry tree, at the moment of cutting, is significantly advanced in the drying process.  Additionally, Naturally Dry timbers have significantly less issues with pockets of tar.  These pockets are a nuisance since they can ooze pitch onto your carpet or floor for years after the beams are installed.

It commonly believed that a timber achieves the most movement when it passes through what is referred to as “the moisture saturation point.”  This point is defined as the point in which mechanical properties of the wood are not meaningfully affected by increased moisture.  With Douglas fir timbers the moisture saturation point is between 24% – 28%.  The reason Naturally Dry timbers perform is that they have already passed through the moisture saturation point prior to cutting.

Lastly, we have been sourcing Naturally Dry timbers for years from multiple locations across the Northwest.  It is our experience that certain regions produce significantly superior fiber than others.  We have carefully identified those regions and only produce Naturally Dried timbers which have grown there, guaranteeing superior performance to any other type of Douglas fir timber available today.

Click here to view our Naturally Dry beams…