Oak beams happen to be a highly durable building material, but these are classified as natural and living products, which means they are associated with various factors which you need to consider before you purchase them.
One of the main questions manufacturers of oak beams get when selling them is “Will they move?” The basic answer to this question is yes. However, the way and how much the beams move is easy to address.
The freshly sawn beams more commonly known as Green Oak beams have been in use for hundreds of years for buildings of all sizes and shapes, so with this in mind they are well tested and very capable. The fresh-sawn beams which are cut directly from trees are used just about immediately, which means these products still have a high moisture content.
The moisture content in the freshly sawn beams often have a moisture content of 75% or more. It is the drying processes of this sap moisture which causes the Oak beams to split, move and settle. The beams dry from the exterior to the interior which causes them to open-up, bend and twist.
If you are looking for beams that will not move, then you need to consider oak beams which have been air-dried. In general, the oak beams that are air-dried are sawn from trees and then left. They stand properly sticked-and-stacked for a period of 5 years or more. In fact, some manufacturers stock air-dried beams that have been left to dry for as long as 15 years sometimes more.
The beams which have been left to dry and settle naturally can offer a moisture content of 20%. This is not to say that these beams won’t move at all, as there is never a guarantee with natural products. However, the air-dried beams can be used with confidence for full-frame house’s onto a fireplace-mantel, knowing movement of these beams once they have been installed is kept to an absolute minimum.