Oak is a versatile building material suitable for many types of building frame structure. It has been used in building construction for as long as people have been erecting permanent dwellings. Archaeological evidence has shown its use in frames for shelters as far back as the Neolithic era. During the time of the Roman empire tenon and mortise joints were first used to create sturdy, stable oak structures. The timber frame of Notre Dame dates back to around 1220 and is thought to have used up to 1,300 trees to construct. From the 12th century onwards oak construction methods were perfected as access to Europe increased its availability in large quantities. Many contemporary oak framed houses use construction techniques largely unchanged from those used in the 15th century.
Oak framed buildings are now more popular than ever, for several practical and aesthetic reasons. While the traditional look of an oak frame still appeals to many, it is equally suited to modern designs. Its production has a lower environmental impact than synthetic manufactured materials and its byproducts are easily recycled without processing. Oak is a carbon neutral building material and its insulating properties can lower the carbon footprint of oak framed buildings. While oak is not a cheap material, it is hard wearing and can last for centuries without replacement.
Types of Oak Frames
There are four main types of building frame structure that can be combined in many ways to give the desired building design. Not all are in common use due to complexity of construction or availability of suitably sized timber.
Cruck Frame
This is one of the oldest designs of oak frame. The trunk of an oak tree is split in half lengthwise to create two matching posts known as cruck blades. These are joined together at the top with a tie beam holding them together towards the top. This creates a large, curved ‘A’ shaped arch that supports the weight of the roof. Posts and rafters of lighter timber are fitted to the outside to create a slanted roof and straight vertical walls. A series of these frames can then be erected with connecting purlins to support the common rafters between them. This type of frame is rare now as it is difficult and expensive to source timber long enough for the cruck blades.
Post and Truss Frame
This is the design most commonly used in modern oak framed buildings. The cross frames consist of a lower section of two vertical posts and a connecting beam at the top. An ‘A’ frame of rafters connected by a tie beam or collar and bracing completes the frame. The base of the rafters connects to the top of the wall posts to form a solid frame that supports the roof. Several of these are then connected by tie beams and oak purlins to complete the structure.
Box Frame
These consist of a series of post and beam frames connected by cross tie beams to form a box like structure. Two or more of these ‘boxes’ can be stacked on top of each other to create multiple storeys. In a box frame the walls support the weight of the roof. The roof consists of a series of principal rafters with collar or tie beams to prevent spreading and bracing posts. The king posts or crown posts between the collar and tie beam prevent lateral movement.
Aisled Frame
In an aisled frame, the principal rafters are extended to first floor level and supported by wall posts. This creates a single storey ‘aisle’ down one or both sides of the frame. This creates additional space on the ground floor and is used in many extension designs.
Oak Framed Building Examples
Most of the examples discussed here can be erected as free standing structures or as an extension to an existing home. As an extension to an oak framed house they can continue and complement the existing aesthetic of the building. As free standing structures they become an eye catching statement piece in their own right. Even if the existing home is masonry or brick built, an oak framed extension can enhance its overall look and add significant value.
Oak Framed Garage
These can be post and truss or box framed, depending on size and number of storeys. Smaller, single story garages will not need to support a heavy roof, so a box frame is usually more economical. Softer wood can then be used for rafters and studwork, although this may need weatherproofing.
Oak Framed Carport
A carport differs from a garage by only being semi covered, with at least 2 sides open. Often this will consist of just an Oak frame and covering roof, but construction methods and design will be similar to a garage.
Oak Framed Garden Room or Conservatory
Designed to incorporate garden areas into the home while still retaining an element of the outdoors. Both feature fully glazed walls to give all round views of garden or grounds but protection from the elements. Conservatories have fully glazed roof sections for maximum illumination. Garden rooms have a fully tiled roof and can be free standing or an extension to the home.
Oak Framed Orangery
Along with garden rooms, these first became fashionable additions in the 17th century but are still popular. Originally, they were used to give warmth and shelter to young citrus trees during the winter. They share the post and truss design of conservatories and garden rooms. However, along with a tiled roof they feature a glazed oak framed ‘lantern’. This is a raised wood and glass section which allows sunlight into the room, providing illumination and warmth.
Oak Framed Garden Buildings
This could be anything from series of oak framed outbuildings for storage and workspace to a traditional oak gazebo. Any will provide a traditional classic look to a garden area and are both eye catching and functional. As oak is naturally weatherproof, they will last a lifetime.
Hardwoods Group produce a wide range of oak framed buildings, manufactured in our workshop and delivered in kit form. These are designed to be simple to erect and produced from the best quality European oak. We can also work with you to design and manufacture bespoke oak frames to suit your needs. If you have a unique design of your own, we can make it a reality. Contact us with any enquiries, we will be happy to help.
