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Pre Engineered Buildings
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Conventional Structural Steel
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1) Design Criteria
A.I.S.C. / M.B.M.A / A.W.S
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1) Design Criteria
A.I.S.C./ A.W.S./ J.I.S./ D.I.N./ B.S.
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2) Design
Quick and efficient since standardization of P.E.B.
has significantly reduced design time. Basic designs
are used over Specialized computer analysis and design
programs reduce design time and optimize material
required. Drafting is also computerized with minimal
manual drawings. Design, detail drawings and erection
drawings are supplied free of charge by the
manufacturer. Approval drawings may be prepared within
10 days to 3 weeks. Consultant in-house design and
drafting design is significantly reduced,
allowing more time for coordination and review, and
increasing margins in design fee savings.
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2) Design
Each conventional steel structure is designed from
scratch by the consultant, with fewer design aids
available to the Engineer. Maximum engineering
required on every project. Generalized computer
analysis programs require extensive input/output and
design iterations. Drafting is manual or only
partially automated.
Much Consultant time and expense is devoted to design
and drafting, as well as coordination and review.
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3) Weight
About 30% lighter through the efficient use of steel.
Primary framing members are designed with tapered
built-up plate sections with the most steel in the
areas of highest stress, using high strength steel.
Secondary members are light gage cold formed "Z" or
"C" shaped members. Members are roll-formed for
minimum weight and labor cost.
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3) Weight
Steel member sizes must be selected from standard hot
rolled sections, which in many cases are heavier than
what is actually required by design. Members are the
same cross-section along the entire length, regardless
of local stress magnitude Secondary members are from
standard hot rolled "I" and "C" sections. In many
cases members are heavier than required, and therefore
are not as economical as cold formed members.
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4) Base Material
Rigid Building P.E.B. System uses almost all steel to
meet 50,000 P.S.l. minimum yield including the
cladding.
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4) Base Material
In most of the cases (90%) Base Material is 36,000
P.S.I. minimum yield.
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5) Foundation
Simple design, easy to construct and lightweight.
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5) Foundation
Extensive heavy foundation required.
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6) Accessories (Windows, Doors, Ventilation)
Designed to fit the system, with standardized,
interchangeable parts, including pre-designed flashing
and trims.
Mass produced for economy. All available with the
building.
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6) Accessories (Windows, Doors, Ventilation)
Every project requires special design for accessories
and special sourcing for each.
Flashing and trims must be uniquely designed and
fabricated.
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7) Delivery
Approximately 8 weeks
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7) Delivery
Average 5 to 6 months.
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8) Erection
Easy, fast, step by step. Erection costs and time are
accurately known, based
upon extensive experience with similar buildings.
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8) Erection
Slow, extensive field labor required. Typically 20%
more expensive than P.E.B.
In most of the cases, the erection cost and time are
not estimated accurately.
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9) Architecture
Outstanding architectural design can be achieved at
low cost. Conventional wall and fascia materials, such
as concrete, masonry and wood, can be utilized.
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9) Architecture
Special architectural design requires research and
high cost.
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10) Overall Price
Price per square meter may be as much as 40% lower
than conventional steel.
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10) Overall Price
High price per square meter.
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11) Sourcing and Coordination
Building is supplied complete with cladding and all
accessories, including erection if required, all from
one source of supply.
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11) Sourcing and Coordination
Many sources of supply. Project Management time
required to co-ordinate suppliers and sub-contractors.
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12) Changes
Very flexible, tailor made, accepts changes and
revisions easily. Future expansion simple, easy and
cost effective. One supplier to coordinate changes.
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12) Changes
Changes, revisions and additions can be difficult due
to extensive redesign and coordination among suppliers
and subcontractors.
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13) Responsibility
Single source of supply results in total
responsibility for one supplier,
including design liability.
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13) Responsibility
Multiple responsibilities can result in questions of
who is responsible when components do not fit
properly, insufficient material is supplied, or
materials fail to perform, particularly at supplier
interfaces. The Consultant carries total design
liability.
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14) Performance
All components have been specified and designed
specifically to act together as a system, for maximum
efficiency, precise fitup, and performance in the
field.
The experience with similar buildings in actual field
conditions world-wide has resulted in design
improvements over time which allow dependable
prediction of performance.
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14) Performance
Components are designed in general for possible use in
many alternative configurations. Design and detailing
errors are possible in assembling diverse components
into unique buildings.
Each building design is unique, so prediction of how
components will perform together is uncertain.
Materials which have performed well in some climates
may not in other environments. |
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Rigid building systems utilize state-of-the-art computer
aided fabrication equipment and technology to assure
customers of high-quality steel products at very
competitive prices. |
