Trades In Construction – Carpentry And Joinery

Carpentry and joinery is concerned with timber works. The difference between the two is:

· Carpentry is concerned with rough timber works, usually en masse and not in much detail. It is concerned with construction works like formwork construction, roof framing, timber scaffolding, et cetera. These are usually site works and can be either temporary or permanent. Most of the procedures here are cutting, splitting and joining.

· Joinery, on the other hand, is concerned with workshop-type of timber works, usually dealing with processed timber and mainly for cabinetry or such works. Most of the timber here is sawn and treated and the works are almost always permanent in nature. Machining of timber is common here, especially to achieve shapes and joints.

Whether carpentry or joinery, the following tasks are common in this trade.

· Cutting: This involves the reduction of size of timber to a consumable size. It is usually the practice to buy timber in bulk and then split it to give smaller pieces as required. Timber is usually measured in body-foot, with one body foot comprising of one inch height by one inch breadth by one foot length. Timber specification is also done in the same manner, for example, “2 x 2 Long 6”. Depending on the quantity and quality required, this cutting can either be done by power chain saws, table mounted power saws or even hand saws. The cutting of other shapes, for example round shapes, is done using workshop machines like the crosscutter.

· Joining: most timber joints are done using hand tools, although mass production uses machines for the same. Common timber joints include mitre, butt and dowel. Gluing is usually done where extra strength is required. Hoop iron is also used like in the case of butt joints. Bolting and nailing is also common in overlapping joints as well as composite joints like timber to metal.

· Finishing: There are various ways of finishing timber, the most common being planning. This is done using planes, whether hand planes like the jack plane or using workshop machines for mass production. Staining and polishing is also common, mainly to bring out the grains as well tone timber to resemble a particular type. Painting is also a common form of timber finish.

It is important to note at this point that carpentry and joinery is concerned with the following variants of materials.

· Softwood: This refers to timber got from exotic trees. These are usually ‘weaker’, owing to the fact that the trees from where they were cut are usually quick maturing and therefore not compact enough. Softwoods are easily attacked by pests and elements of weather and are therefore not recommended for exposed and long-term works.

· Hardwoods: This is the timber that is got from deciduous type of trees. They are usually very strong and robust. They also offer a good aesthetic finish and are therefore common in furniture and stained panels. Trees offering this timber include mahogany, meru oak and camphor.

· Manufactures timber: The most common products here are boards like hardboard, plywood and MDF. They are factory manufactured and therefore meant for specific purposes, owing to their quality at manufacture.