Category: TIMBER AND INDUSTRIAL TIMBER PRODUCTS

Only processed timber can be used provided they are made out of reliable materials. However, doors and other wooden fittings should be restricted to wet areas like the bathroom.

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Generally, wood for building construction is not tested in the laboratory. It is a practice to classify them by their species and by visually examining them for defects. However, the following tests are conducted for important works: Tensile Strength Test The specimen used for tensile strength test is of size 5 cm × 5 cm…

To increase the life span of wood, they should be treated with chemicals–this process is known as the preservation of timber. Requirements for a Good Preservative A good preservative should fulfil the following requirements: Types of Preservatives There are three types of preservatives with different bases as prescribed in the Code (IS: 401–2001). 1. Oil…

Once the woods get deteriorated they lose their engineering properties and the wood is said to be decayed. Several reasons contribute to the decay of wood, which are explained below:

Trees felled recently will contain large amounts of sap and moisture. Seasoning is the process of removing all the sap and moisture content under controlled conditions to avoid any splitting and distortion in the wood. Objectives of Seasoning Although the primary aim is to remove sap and moisture, the other objectives of seasoning are as…

After felling trees, the branches are removed and the trunk is cut into logs. Conversion is the process of cutting and sawing logs into suitable sections of timber. In earlier days, it was done manually using saws. Now-a-days, cutting is done by band and circular saws run by machines. Sawing is done by four methods,…

Different kinds of defects are found in timber. Generally, they are caused by the nature of the soil on which the tree is grown, the fertility it gained during growth and changes occurred in the environment during its growth. The defects to be generally looked into while selecting timber for woodwork are discussed below. Knots…

Characteristics of good timber are given below in the order of decreasing significance: Strength The timber should be strong enough to effectively act as structural members, such as joists, beams, rafters, etc. Further, it should be in a position to sustain loads applied gradually or suddenly to it. Preferably, the strength should be adequate in…

As per Indian Standards (IS: 4021–1967), it is preferred that timber used for building construction purposes is of one of the following four types: Classification of Teak Teakwood is classified into three grades, viz., superior, first and second depending on the defects. The classification of teak based on the permissible defects, viz., cross grain, knots, pith, pockets or streaks, sapwood,…