Trusses are use as structural element for roofing works in any building. There are two types of material being used; timber and steel. Among these, timber is frequent use. It has been selected; because it is more economical if compare to steel trusses in country like Malaysia (Timber is one of resources of Malaysia).
One of the duties of consulting engineer is to design and supervises the construction of truss. Since timber trusses are common used in Malaysia, there is another group of people who start manufacturing timber truss which we call the prefabricate trusses. These groups of people will undertaking the task of design, fabricate and construction of trusses at site. It comes to a point that consulting engineer has to check and approve the design of
When trusses fabricator undertakes the task of design, consulting engineer has to check and verify the design of trusses is fit, safe and structurally sound. Now days, most of the design is carry out by computer software and the accuracy is achievable. Therefore, engineer has to work on another part by verifying certain items that needs to consider in design. Below will be some guidelines that need to consider when design of trusses.
First is the loading. What are the roof components use and their weights? As for example, timber roof tiles. Is comprises of roof tiles, timber battens, timber trusses and ceiling. Engineer has to identify that these material weights and has been incorporate into design.
Second is to identify that it comply with theory of trusses. Trusses are modeled to its theory. Else, it will cause stability of trusses.