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The differences between PEBs and conventional steel buildings

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Pre-engineered vs Conventional Steel Buildings

Structure: Pre-Engineered Conventional Steel Buildings
Weight: Pre-engineered buildings (PEBs) are on average 30% lighter through the efficient use of steel. Primary framing members are tapered (varying depth) built-up plate sections, with larger depths in the areas of highest stress. Secondary members are light gauge (lightweight), roll-formed (low labour cost) "Z" or "C" shaped members. Primary steel members are selected from standard hot-rolled "I" sections, which are, in many segments of the members, heavier than is actually required for box design. Members have constant cross-sections regardless of the varying magnitude of the local stresses along the member length. Secondary members are selected from standard hot-rolled "I" and "C" sections, which are heavier.
Design: Quick and efficient: since PEBs are formed mainly of standard sections and connections, design time is significantly reduced. Basic designs can be used again and again. Specialised computer analysis and design programs optimise the material required. Drafting is also computerised using standard details that minimise a project's custom details. Design, shop detail sketches and erection drawings are supplied free of charge by the manufacturer. Approval drawings are usually prepared within 2 weeks. PEB engineers design and detail pre-engineered buildings almost every day of the year resulting in faster and more efficient designs. A consultant's in-house design and drafting time is considerably reduced, allowing more time for coordination and review. Each conventional steel structure is designed from scratch by a consultant, with fewer design aids available to the engineer. Substantial engineering and detailing is required on every project. Generalised computer analysis programs require extensive input/output and design alterations. Extensive consultant time is devoted to design and drafting, as well as coordination and review, often at significant expense. Each project has to be handled as a separate case, and engineers need more time to develop the designs and details of the unique structure. More complicated designs require more extensive design and drafting consultancty time.
Delivery: Average 6 to 8 weeks Average 20 to 26 weeks