Timber Frame Construction

1) Why are the insulated enclosure walls for a modern timber frame structure generally located on the outside of the timber frame?

The insulated enclosure walls for a modern timber frame structure are generally located on the outside of the timber frame:

• To protect the timber frames against severe climate.
• Minimal thermal loss.
• Easy to install.
• To protect from moisture damage.
• Using the panels on outside of the timber frame gives additional strength to the home.

2) What are the important factors in detailing the junction of a major beam with a column in a timber frame structure? Draw several ways of making this joint?

     The junction of a major beam structure can be made by mortise and tenon joint as shown in the figure mentioned below. This joint is also known as the work horse of a timber frame. The shaped grits on the main beam is connected onto the post using a tapered cut or a rectangular cut. The important factor in detailing the junction of major beam with a column is, the placed bearing surface on the post should be able to support the vertical loads imposed by the beam connected to the column.

The two ways of making mortise and tenon joint is shown in the below figure.

3) Name several sources of quality timbers for timber frame buildings constructed today.

       Now-a-days, the construction industry is consuming large quantities of timber. Rain forests of countries such as Brazil and Indonesia is the source of quality timbers. Timber is one of the most conservative building materials among all. Demand of tropical hardwood leads to an illegal deforestation on rain forests regions. A tropical country gives 35% of world’s production of wood. But, most of the international woods are comes from South Asia because of their richness in forest region.62% of legal timbers are exported from tropical region to Japan and 22% are from Indonesia.

4)  What are the typical problems in routing utilities through a timber frame structure? How are these problems usually resolved?

The typical problems in routing utilities through a timber frame structure are listed below:

• When timber is exposed to a weather bulking and shrinking may happen.
• Poor maintenance.
• Unsuitable renovation and fall.
• Distortion (Removal of studs).
• Fungal attack or decay from beetle

These problems are resolved using the following steps:

• Should not replace or distort the timber frames unnecessarily.
• In the case of serious decay the damaged section can be replaced with new timber.
• We can also strengthen the timber frames using steel instead of wooden pegs in the joints.

EXERCISES: 

3) Find a barn or mill that was constructed in the 18th or 19th century and sketch some typical connection details. How is the structure stabilized against horizontal wind forces?

The connection details used in the barn which is build in the 18^th century is discussed below with respective sketches:

Column – Beam Mortise and Tenon joint

                         

The mortise and tenon joints used to connect the posts and beams is shown in the figure. The beam and loads are not resting solely on the tenon.

Sill Joineries

From the 18^th century sill joineries are made by right angle mortise and tenon joints and an extra mortise is to support tenon from the posts. The timber sill joinery is used to add more strength, authenticity and longevity.

The structure is stabilized against horizontal wind forces due to the bracings placed between the posts. Due to the proper bracings in post and beam joints it is capable to transfer all lateral loads and horizontal wind loads.