A green oak frame can be erected very quickly indeed - even a large one...
As it is mainly a matter of reassembling and pegging the constituent frames created in the workshop, installation usually takes place very rapidly causing a minimum of noise and disruption. In a very short time it gives rise to a fully formed self-supporting structure.
Depending on the nature of the project, the masonry or foundations will have been marked for levels, setting out points and tying in points.
The timbers are unloaded and stacked in sequence ready for use as close as practicable to the build area and a clear marshalling area set aside for organising and assembling the frame. Where timbers are to be manoeuvered by crane, space must be allowed for the crane to gain access and operate within reach of both the marshalling and build areas.
They are set out and fixed in predetermined positions relative to the established setting out points over a damp-proof course to prevent any transfer of moisture from the masonry.
When the sole plates are level and square, the posts can be put into position along with their braces in readiness for the next layer of timbers.
In this respect, there is always a strict sequence of fitting which must be followed.
As the build progresses, the frame rapidly takes shape. In a relatively short period of time the series of timbers placed along the top of the masonry give rise to a fully formed structure.
Although the vast majority of the carpentry work is performed in the workshop, there are always a few minor tasks to be carried out on site throughout the build.
They vary according to the nature of the project, though invariably include the drilling of fixing points between frame and masonry. With this in mind, it is important to have access to a nearby electricity supply to provide power to essential site tools.
With the lower part of the frame erected, or masonry walls prepared and the wall plates in position, the roof timbers can be put into place.
Where the roof timbers form part of the lower structure too (as with cruck or sling braced frames), these different stages are usually merged into one.
At Sessile Oak, we use only high quality oak pegs made from straight-grained
timbers of a low moisture content. Not only does this make them stronger when
driven home, it also means that they are less prone to shrinkage as the frame
matures - ensuring a tight fit as the years pass.
Initially, joints are often held in place by podgers in place of the pegs to allow for the maneuvering of timbers. Even without any of the pegs in place, the frame can be completely rigid and self-supporting.
Before too long, the frame is up, pegged and ready for the next stage of the project.
In the meantime, the frame should be made secure against the elements without delay to prevent unnecessary water-marking.
Take a wander through our oak frame gallery and view some of the green oak building projects we've completed over the years. From simple entrance porches to modern cutting edge sun rooms and extensions, there's something for every green oak enthusiast to enjoy.
Where a frame is to be installed upon an existing structure (eg. on masonry walls) or constructed to a height which cannot be reached safely from ground level, scaffolding is erected to provide a secure working platform. Where work is to be carried out at lower heights or between trusses, staging boards are used. They can be placed on trestles or tie beams in order to straddle bays to allow the fitting of roof timbers.
Ladders are essential on any construction site. It is important to secure them at the top to prevent movement. They should also be removed at the end of every working day for safety and security.
Timbers are commonly marshalled with a small trolley. Whilst very maneuverable, they can become unstable on uneven ground or when encountering an obstruction, so it is best to maintain a clear and tidy site.
On larger projects, or even where a single large timber is to be lifted, it is often necessary to hire a crane and operator. The size varies according to the weight and distance to be lifted. Provision is made for access and a 'banksman' is designated to direct the operator via either hand signals or radio.
Building sites are amongst the most hazardous of working environments. It is vital that everybody on site is properly equipped to work safely and efficiently. As an absolute minimum, personal kit must always include: helmet; safety boots; ballistic goggles; ear protectors; safety harness for working at height, and; hi-viz clothing. Where masonry is to be cut, an "air-fed" respirator is recommended.
Everyone on site must have a clear understanding of their role and responsibilities. Any ambiguity has the potential to cause oversight and mishap.
All site personnel must know the location of all first aid equipment, the nearest telephone and the site address. Qualified "First Aiders" are identified so that necessary treatment may be administered immediately.
Generally, green oak construction will not involve the use of harmful substances. If adhesives are required, they are applied carefully and any residue cleaned and removed from site.
A new, yet significant, consideration is the need for biosecurity against the spread of COVID-19. As threat levels vary with the emergence of new variants, we will strive to maintain safe working practices. More detail, plus links to government guidance, can be found on our Pandemic Policy.
An overview of approaches to glazing a green oak frame with either direct or externally fixed units or frames.
A frame will need to be cleaned once it is in place and shielded from the elements.
