The Tamar Joinery Company
Green Oak Timber Framed Buildings and bespoke joinery
Telephone (Tavistock, Devon) 01822 840848
e mail firstname.lastname@example.org
|Traditional Timber Framing|
The Woodyard and Sawmill
Our Heartwood Sawmill
Our sawmill allows us to process fine locally grown timber for our timber framing projects and we also retail timber in non-standard sizes to fellow craftspeople and manufacturers. We sawmill unseasoned timber to customer order. We are committed to supporting our local forestry industry which will encourage the managed sustainable production of timber as a carbon neutral building material.
We will cut timber to size according to your order. Size can range down from massive maximum dimension of 680mm square with a maximum length of 6.88 metres.
Structural Beams are cut to size from green (unseasoned) English Oak, Douglas Fir or Sweet Chestnut.
Timber can be supplied waney edged, sawn to size or machined into bespoke components. Please contact us for a quote.
Plain or Flat Sawn
Green Oak or Douglas Fir Beams and trusses
We sawmill beams to order from green (unseasoned) locally grown English Oak, Douglas Fir or Sweet Chestnut. Beams can be supplied rough sawn or planed all around. The beams can be machined as required.
Although English Oak is the most commonly used timber for traditional timber framing, Douglas Fir is strong, durable and is a great alternative to Oak in construction.
Below, Tom is cutting a stop champfer on a Douglas Fir beam.
Air dried timber: We always carry a large stock of air dried English Oak which we sawmill and leave 'stickered' to allow air circulation in our open sided drying shed.
Freshly sawn Douglas Fir used in a traditionally constructed timber frame
With our sawmill we can cut a wide variety
of home grown custom milled beams, wooden lintels, mantel pieces and fireplace
surrounds from locally sourced timber.
Variations in timber conversion
The diagrams below show standard flat sawn cut and quarter sawn cuts. The quartersawn log is far more complex and time consuming to sawmill. The black triangle in the quarter sawn log will be wasted.
Quarter Sawn Timber
Shown below is a quarter sawn oak plank, prized for the rich decorative 'fleck'. This cut of timber is attractive but it is also the most stable cut for planks of oak which means that it is perfect for panel work and fine furniture. The decision to install our own sawmill some 12 years ago was driven by our need to secure the high quality timber we want to use in our projects, including quarter sawn oak for traditional oak panelling and other projects which require the best, most stable and beautiful timber.
Green, Air Dried or Kiln dried timber
Air-dried Air-dried and kiln-dried timber have a lower moisture content which makes it more predictable and less likely to move.Air dried timber is cut and stored in an open sided shed to dry naturally. Air circulates between the timbers, which are each separated by evenly placed 'stickers', gradually reducing the moisture content. On average it will take one year to dry 25mm of Oak and so seasoning can take anything from three to ten years depending on the thickness of the Oak. The moisture content of air-dried Oak should be around 20-30%.
Kiln-dried Kiln Dried refers to timber which has undergone an artificial drying process whereby the moisture is drawn out of the timber by increased air circulation and/or heat and humidity control. The kilning process is more controllable than natural seasoning, enabling the timber to be dried to a lower moisture content and hence making it suitable for internal environments although all Oak must undergo a period of natural seasoning first.
Which type to use
Green Oak, Sweet Chestnut or Douglas Fir would be our timbers of choice when it comes to traditional timber frames, roof trusses, beams and posts. The timber is 'soft' and easier to cut and shape. More importantly, as the timber starts to dry, it shrinks slightly across the width of the grain pulling the joints tight and hardening to increase the overall strength of the oak frame. This shrinkage is integral to the design and detailing of the timber frame.
Air-dried timber has already dried a little and developed the cracks and splits that occur during the drying out process. Generally, air dried timber is suited to exterior use as its naturally dried to a moisture level consistent with the outdoor environment. It works well if movement needs to be minimal and when thicknesses of 75mm or less are required for example, lintels, glazed panels and window frames. Air-dried oak beams can also be suitable for renovation and restoration projects where the oak will be jointed into an existing frame. The natural seasoning process produces a stable timber that is also very well suited to external applications such as gates, exposed external doors, balustrades, cladding and decking. For cladding, we would generally use partly air dried Oak, Sweet Chestnut, Western Red Cedar or Douglas Fir.
Kiln Dried timber is dried to a further level making it well suited to the typical indoor environment. Great care must be taken during the kiln drying to ensure the process does not occur too quickly. If Oak is kiln-dried too quickly, or if the drying proceedure is not uniform, instability and damage to the structure of the wood can occur. It is an expensive process in time, energy consumption and rejected timbers. In common with air-dried timber, kiln dried timber is mainly used for flooring, fireplace mantels, and furniture.
Kiln Dried Timber: We always have a stock of kiln dried material. Please contact us for a quote.
Our Trekkasaw - This portable sawmill is used occassionally for cutting wider and longer slabs than is possible on our fixed Heartwood sawmill.
Oak, Sweet Chestnut or Douglas Fir feather cladding
Sweet Chestnut feather edge cladding being installed below.