Oak Framing FAQs

Oak is prepared in a variety of ways for construction, each to suit the particular way in which it is employed. Green oak is the traditional and still the best material for making oak frames. At this early stage, its high moisture content means that it is easy to work with minimal effort and wear on cutting tools. Over time, it will dry and age naturally as the moisture content reduces and it is this very process that makes traditional oak timber framing what it is and has produced the thousands of historic buildings that surround us. Air dried oak is naturally dried, usually in a dry, outside store before it is used. The moisture content reduces very gradually, eventually reaching 20-30%, by which time it becomes harder and more challenging to cut. Drying can take anywhere from three to ten years for large pieces of oak. It is best used for outdoor structures such as gates and garden architecture, or for renovation projects where it is joined to oak that is already dry. Some claim to make their frames from air dried oak although with the very lengthy drying times for large sections of timber this seems unlikely due to the prohibitive cost of prolonged storage to produce truly air-dried timber. Kiln dried oak shares the same properties and applications as air dried oak, but the drying process is accelerated using heat. This timber is really for use in furniture and other joinery manufacturing.

Fitting glass to an oak frame, which will shrink and move over its lifetime, can be tricky. If not carried out correctly, when the oak moves there’s a chance that it will create a gap between the glass and let in moisture. Some companies cut a rebate in the wood to accept the glazing unit. The problem with this approach is that it doesn’t allow for the oak to move and shrink with the possibility of leaving gaps as well as putting undue pressure on the glass. Many years of experience has taught us that rather than rebating, a face-planted (or face-fixed) approach is more robust. This technique maintains the integrity of the seal with the glass and looks better too.

In our view, the looks, character and longevity of oak make it the ultimate material for constructing wood buildings. For that reason, our usual approach is to specify every part of the structure in oak. If you would prefer more of a ‘hybrid’ build, we can recommend where to use softwood for a project without compromising the structure. If your main motive for considering the use of softwood is budget, please be aware that in practice its use doesn’t often result in big savings.

Building regulations dictate that any habitable structure we create must be insulated to meet or exceed current control standards. Exposed rafters are a common feature in oak buildings, and our use of an insulation ‘sandwich’, which sits between the rafters and the tiles, ensures that our buildings look good and stay warm too.

The choice of how to correctly join sections of oak is critical to the integrity of your building. Whether you are looking for a traditional or contemporary look, we use time-honoured mortice and tenon joints to ensure a strong and durable construction. Handmade tapered oak pegs secure all of the joints connecting the larger principle timbers.

The choice of roof is entirely dependent on the look you want to create. We have completed projects using every type of roofing possible, from traditional clay tile, slates, shingles, lead or thatch to more modern engineered sheet materials. It’s fair to say that most of our buildings are finished with traditional clay tiles.