|SL. No.||Pre Engineered Buildings (PEBs)||Conventional Steel Buildings|
|Frames of pre-engineered buildings are made from an extensive inventory of standard steel plates stocked by the PEB manufacturer, PEB frames are normally tapered and often have flanges and webs of variable thicknesses & depth along the indidual members.|
The frame geomentry matches the shape of the internal stress (bending moment) diagram thus optimizing material usage and reducing the total weight of the structure.
|In conventional steel buildings mill-produced hot rolled sections (beams and columns) are used. The size of each member is selected on the basis of the maximum internal stress in the members.
Since a hot rolled section has a constant depth, many parts of the member (represented by the hatched area), in areas of low internal stresses are in excess of design requirements.
|1||PEBs are on an average about 30% lighter due to efficient use of steel. Primary framing members are usually tapered (varying depth) built-up sections with large depths in areas of higher stress.||Standard hot rolled “I” or “C” sections are used, which are in many segments much heavier than what is actually required as per design.|
|2||Quick and efficient designing due to well defined international design standards & codes and employing specialized computer programs/ software.||Each conventional structure is designed from scratch by the consultant with fewer design aids available.|
|3||Detailed design, shop detail sketches, erection drawings & sheeting drawings etc are provided free of cost by ISB, thereby considerably reducing erection & sheeting time.||Extensive amount of consultant’s time is devoted to design, drafting & detailing as well as co-ordination and review of on-site activities resulting in considerable delay & expenses.|
|4||All structures are manufactured in our factory under strict quality control environment, thereby ensuring superior quality & finish||Structures are mostly site fabricated wherein it is difficult to monitor & control quality parameters.|
|5||Easier sourcing & co-ordination due to single source responsibility as the entire building alongwith all the sheeting & accessories is designed, supplied & erected by ISB.||Multiple sources for different items are involved, thereby causing considerable expenditure & delay.|
|6||Superior architectural features can be incorporated and excellent aesthetics can be achieved||Limited scope for architectural & aesthetic features.|
|7||Easier to incorporate future expansions due to modular nature of design.||More difficult to incorporate expansions.|
|8||Single source of supply results in total responsibility by ISB including Design Liability.||Multiple sources/ responsibilities can lead to questions of who is responsible when different components do not fit together properly, or insufficient material is supplied, or when components/ the entire system fail to perform.|
|9||Faster completion time - as civil works can be completed parallely.||Much slower completion time.|
|10||Cost per SQM is about 30% cheaper than conventional structures.||Cost is higher due to higher consumption of steel and other co-ordination issues involved.|