PEB vs HOT ROLLED BUILDINGS
| Feature | Pre-Engineered Steel Buildings | Hot Rolled Buildings |
|---|---|---|
| Design Criteria | AISC, MBMA, AWS | AISC, AWS, JIS, DIN, BS |
| Structural Base Material | All primary and secondary steel used by JK has a minimum yield strength of 50 KSI (345 N/mm2). | In most cases, the primary and secondary steel used has a minimum yield strength of 50 ksi KSI (250 N/mm2). |
| Foundation | Simple design, easy to construct and lightweight. | Extensive heavy foundations required. |
| Delivery | Average 6 to 8 weeks | Average 20 to 24 weeks |
| Sourcing & Coordination | Building is supplied complete including roof and all accessories, all supplied from a single source. | Many different sources of supply, with an additional time requirement for the Project Management to co-ordinate deliveries & erection. |
| Structure Weight | About 30% lighter through the efficient use of steel. Primary members are tapered built-up sections with large depths in the areas of highest stress. Secondary members are light gage, cold formed steel with a low labor count "Z" or "C" shaped members. Z purlins/girts reduce labor count. Lapping reduces the deflection, and allows double thickness at the points of higher stresses (support points). | Primary steel members are selected from standard hot rolled "I" sections, which in most cases uses more steel than what is actually required by design due to availability in the market. The same constant cross-sections along the entire span, regardless of local stress magnitude (secondary members8 are selected from standard hot rolled "L" or channel sections and weigh as much heavier than required |
| Design | Quick and efficient since standardization of PEB has allowed for reduced design time. Basic designs are used over and over. Specialized computer programs are used to optimize reduce design time and optimize design required. Drafting is also computerized (automated) manual drawing, erection drawings, and the erection drawings are supplied directly from the computer of the manufacturer. Approval drawings may be prepared within 10 days to 3 weeks. Consultant in-house approval and permit processing significantly reduced, allowing more time for coordination and review, and increasing margins in design fees. Since most PEBs are pin-based, the cost is reduced due to smaller footing, reduced excavation, and base plates and foundations (in absence of moment). | Each conventional steel structure is designed from scratch by the Consultant, with lesser design aids available to the Engineer. Minimum engineering required on every project. Generalized computer analysis programs available; however, require some design alterations. Drafting is manual or only partially automated. Significant time and expense on consulting services are devoted to design and drafting, as well as coordination and review. |
| Accessories Windows, Doors, Ventilation etc | Designed to fit the system, with necessary interchangeable parts including pre-designed flashing systems. Mass produced for the economy. All available with the building | Every project requires special design for accessories and special sourcing for each component. Each assembly is uniquely designed and fabricated |
| Erection | Easy, fast and efficient. Erection costs and time are accurately determined based upon extensive experience with similar buildings. | Slow, extensive field labor required. Typically 30% more expensive than a normal PEB building due to the difficulty to estimate erection costs and time. |
| Architecture | Outstanding architectural design of line roof. Compatibility with and fascia materials, such a masonry, masonry, and wood, can be utilized. | Special architectural design requires research, more time and higher cost. |
| Overall Price | The average savings may be as much as 40% over conventional steel. | High price per square meter. |
| Changes | Flexible, tailor made, changes and revisions made easily. The future expansion is simple, easy and economical to design and co-ordinate changes. | Changes, revisions, and additions can be difficult due to extensive redesign and co-ordination with engineers and subcontractors. |
| Performance | All components have been specified and designed together, resulting in a complete system, for maximum efficiency, reliability and compliance with the specified field conditions. Continuous long term guarantees over time allow for dependable prediction of performance. | Components are designed in general for possible use in many different structures. Design and detailing errors are difficult with customizing diverse components into the unique buildings Each building design is unique, so prediction of the how new components will be perform together is uncertain. Materials which have performed well in one climate may not in other environments. |
| Responsibility | Single source of supply results in total responsibility for one supplier, reducing exposure of owner and consultant. | This risk is unacceptable since when components do not fit properly, insufficient material supplied, or materials fail to perform, particularly at supplier interfaces. The consultant carries total design liability. |
About 30% lighter through the efficient use of steel. Primary members are tapered built-up sections with large depths in the areas of highest stress.
Secondary members are light gage, cold formed steel with a low labor count "Z" or "C" shaped members. Z purlins/girts reduce labor count.
Lapping reduces the deflection, and allows double thickness at the points of higher stresses (support points).
Quick and efficient since standardization of PEB has allowed for reduced design time.
Basic designs are used over and over. Specialized computer programs are used to optimize reduce design time and optimize design required.
Drafting is also computerized (automated) manual drawing, erection drawings, and the erection drawings are supplied directly from the computer of the manufacturer.
Approval drawings may be prepared within 10 days to 3 weeks. Consultant in-house approval and permit processing significantly reduced, allowing more time for coordination and review, and increasing margins in design fees.
Since most PEBs are pin-based, the cost is reduced due to smaller footing, reduced excavation, and base plates and foundations (in absence of moment).
Each conventional steel structure is designed from scratch by the Consultant, with lesser design aids available to the Engineer.
Minimum engineering required on every project. Generalized computer analysis programs available; however, require some design alterations. Drafting is manual or only partially automated.
Significant time and expense on consulting services are devoted to design and drafting, as well as coordination and review.
Designed to fit the system, with necessary interchangeable parts including pre-designed flashing systems.
Mass produced for the economy. All available with the building
All components have been specified and designed together, resulting in a complete system, for maximum efficiency, reliability and compliance with the specified field conditions.
Continuous long term guarantees over time allow for dependable prediction of performance.
Components are designed in general for possible use in many different structures.
Design and detailing errors are difficult with customizing diverse components into the unique buildings
Each building design is unique, so prediction of the how new components will be perform together is uncertain.
Materials which have performed well in one climate may not in other environments.
This risk is unacceptable since when components do not fit properly, insufficient material supplied, or materials fail to perform, particularly at supplier interfaces.
The consultant carries total design liability.