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Self-framing metal buildings are a form of pre-engineered building which utilizes roll formed roof and wall panel diaphragms as significant parts of the structural supporting system. Additional structural elements may include mill or cold-formed elements to stiffen the diaphragm perimeters, transfer forces between diaphragms and provide appropriate. As with most pre-engineered buildings, each building will be supplied with all necessary component parts to form a complete building system.
Regardless of project site location, buildings must be designed in accordance with appropriate engineering due diligence. Buildings should be designed for all applicable loads including the following:
Engineered structural design must comply with the applicable sections of the latest edition of the "Specification for Structural Steel Buildings" of the American Institute of Steel Construction (AISC) and the "Specification for the Design of Cold Formed Steel Structural Members" of the American Iron and Steel Institute (AISI).
Many areas of the United States require the use of state or local building codes which may differ from the "International Building Code". Building codes such as the "International Building Code" and Uniform Building Code (UBC) are markedly different from each other and are often revised at the local level.
Self-framing buildings are within the scope of the National Building Code of Canada (NBCC) as adopted and modified by each Province and Territory. For steel structures, NBCC references CAN/CSA S16 Design of Steel Structures and CAN/CSA S136 North American Specification for the Design of Cold-Formed Steel Structural Members.
Manufacturers are required to be certified in accordance with CSA A660 Certification of Manufacturers of Steel Building Systems. Among other requirements, the manufacturer must supply drawings and documents sealed by a professional engineer licensed in the province or territory of the project site. A Certificate of Design and Manufacturing Conformance, duly completed by an engineer knowledgeable with the design and manufacturing, must be provided to the owner and submitted to the Authority Having Jurisdiction (AHJ)with the permit application.
The building code requires documents to be adequate to allow a review of the structural competence of the building (e.g. NBCC Part 4). The Authority Having Jurisdiction will usually require drawings expressing architectural aspects (e.g. Parts 3, 5 and 11). Due to the limited complexity and size of self-framed buildings, the manufacturer's drawings are frequently accepted for this purpose but the owner should be aware that this may not always be the case.
Exterior roof panels are usually a single continuous length from eave to ridge line for gable style buildings or from low eave to high eave on single slope or shed style buildings. Many manufacturers provide minimum 24 gauge (nominal: 0.0239 inch; 0.61 mm) thick sheet steel in self-framing roof designs.
Exterior wall panels are usually a single continuous length from the base channel to the eave of the building except where interrupted by wall openings. Many manufacturers provide minimum 24 gauge (nominal: 0.0239 inch; 0.61 mm) thick sheet steel in self-framing wall designs.
Diaphragm or racking strength of the wall and roof systems are dependent on issues such as the manufacturer's panel lap seam assembly and should be qualified by full-scale testing. Openings reduce the local structural capacity of the wall or roof assembly and should be considered in the original structural design. the manufacturer may provide guidance for limited field modifications for additional openings.
Building width: 3 m (10' +/-) to 10 m (32' +/-) is common. Width is primarily limited by the capability of the roof panel to support the applied gravity loads (e.g. self-weight, snow) and wind uplift loads. In taller buildings, the wall panel may be a limiting factor to width due to buckling of the unsupported wall panel length.
Building length: 3 m (10' +/-) to 10 m (32' +/-) is common. Length is primarily limited by the ability of the load path to transfer loads to a vertical brace system (e.g. gable endwall). Building length can be extended with added discrete brace systems (e.g. roof level horizontal brace, portal frame, diagonal brace, interior partition shear wall).
Building height: 2.5 m (8' +/-) to 7.5 m (24' +/-) is common. Height is primarily limited by the capability of the wall panel to support the wind load. Height may be limited in narrow buildings due to shear capacity limit in the gable endwalls.
Many manufacturers publish tables relating loads to building dimensions and limitations (e.g. ratio of partial height panels to full height panels where wall openings are required).
Typically, self-framed buildings will be shipped to site in knocked-down condition with all parts and hardware. Smaller self-framed buildings may be fully assembled at the manufacturer's facility and transported to site.
The project architect, sometimes called the Architect of Record, is typically responsible for aspects such as aesthetic, dimensional, occupant comfort and fire safety. When a pre-engineered building is selected for a project, the architect accepts conditions inherent in the manufacturer's product offerings for aspects such as materials, colours, structural form, dimensional modularity, etc. Despite the existence of the manufacturer's standard assembly details, the Architect remains responsible to ensure that the manufacturer's product and assembly is consistent with the building code requirements (e.g. continuity of air/vapour retarders, insulation, rain screen; size and location of exits; fire rated assemblies) and occupant or owner expectations.
Many jurisdictions recognize the distinction between the project engineer, sometimes called the Engineer of Record, and the manufacturer's employee or subcontract engineer, sometimes called a specialty engineer. The principal differences between these two entities on a project are the limits of commercial obligation, professional responsibility and liability.
The structural Engineer of Record is responsible to specify the design parameters for the project (e.g. materials, loads, design standards, service limits) and to ensure that the element and assembly designs by others are consistent in the global context of the finished building.
The specialty engineer is responsible to design only those elements which the manufacturer is commercially obligated to supply (e.g. by contract) and to communicate the assembly procedures, design assumptions and responses, to the extent that the design relies on or affects work by others, to the Engineer of Record – usually described in the manufacturer's erection drawings and assembly manuals. The manufacturer produces an engineered product but does not typically provide engineering services to the project.
In the context described, the Architect and Engineer of Record are the designers of the building and bear ultimate responsibility for the performance of the completed work. A buyer should be aware of the project professional distinctions when developing the project plan.
Lumber, also known as timber, is wood that has been processed into beams and planks, a stage in the process of wood production. Lumber is mainly used for structural purposes but has many other uses as well.
A truss is an assembly of members such as beams, connected by nodes, that creates a rigid structure.
A structural insulated panel, or structural insulating panel, (SIP), is a form of sandwich panel used in the construction industry.
Tilt-up,tilt-slab or tilt-wall is a type of building and a construction technique using concrete. Though it is a cost-effective technique with a shorter completion time, poor performance in earthquakes has mandated significant seismic retrofit requirements in older buildings.
A curtain wall is an outer covering of a building in which the outer walls are non-structural, utilized only to keep the weather out and the occupants in. Since the curtain wall is non-structural, it can be made of lightweight materials, such as glass, thereby potentially reducing construction costs. An additional advantage of glass is that natural light can penetrate deeper within the building. The curtain wall façade does not carry any structural load from the building other than its own dead load weight. The wall transfers lateral wind loads that are incident upon it to the main building structure through connections at floors or columns of the building. A curtain wall is designed to resist air and water infiltration, absorb sway induced by wind and seismic forces acting on the building, withstand wind loads, and support its own weight.
This page is a list of construction topics.
Fazlur Rahman Khan was a Bangladeshi-American structural engineer and architect, who initiated important structural systems for skyscrapers. Considered the "father of tubular designs" for high-rises, Khan was also a pioneer in computer-aided design (CAD). He was the designer of the Sears Tower, since renamed Willis Tower, the tallest building in the world from 1973 until 1998 and the 100-story John Hancock Center.
In structural engineering, a shear wall is a vertical element of a system that is designed to resist in-plane lateral forces, typically wind and seismic loads. In many jurisdictions, the International Building Code and International Residential Code govern the design of shear walls.
A rafter is one of a series of sloped structural members such as wooden beams that extend from the ridge or hip to the wall plate, downslope perimeter or eave, and that are designed to support the roof shingles, roof deck and its associated loads. A pair of rafters is called a couple. In home construction, rafters are normally made of wood. Exposed rafters are a feature of some traditional roof styles.
A tie, strap, tie rod, eyebar, guy-wire, suspension cables, or wire ropes, are examples of linear structural components designed to resist tension. It is the opposite of a strut or column, which is designed to resist compression. Ties may be made of any tension resisting material.
ISO 13567 is an international computer-aided design (CAD) layer standard.
Cross-laminated timber (CLT) is a wood panel product made from gluing together layers of solid-sawn lumber, i.e., lumber cut from a single log. Each layer of boards is usually oriented perpendicular to adjacent layers and glued on the wide faces of each board, usually in a symmetric way so that the outer layers have the same orientation. An odd number of layers is most common, but there are configurations with even numbers as well. Regular timber is an anisotropic material, meaning that the physical properties change depending on the direction at which the force is applied. By gluing layers of wood at right angles, the panel is able to achieve better structural rigidity in both directions. It is similar to plywood but with distinctively thicker laminations.
In structural engineering, the open web steel joist (OWSJ) is a lightweight steel truss consisting, in the standard form, of parallel chords and a triangulated web system, proportioned to span between bearing points.
Earthquake-resistant or aseismic structures are designed to protect buildings to some or greater extent from earthquakes. While no structure can be entirely immune to damage from earthquakes, the goal of earthquake-resistant construction is to erect structures that fare better during Seismic activity than their conventional counterparts. According to building codes, earthquake-resistant structures are intended to withstand the largest earthquake of a certain probability that is likely to occur at their location. This means the loss of life should be minimized by preventing collapse of the buildings for rare earthquakes while the loss of the functionality should be limited for more frequent ones.
Cold-formed steel (CFS) is the common term for steel products shaped by cold-working processes carried out near room temperature, such as rolling, pressing, stamping, bending, etc. Stock bars and sheets of cold-rolled steel (CRS) are commonly used in all areas of manufacturing. The terms are opposed to hot-formed steel and hot-rolled steel.
The Metal Building Manufacturers Association (MBMA) was founded in 1956 and promotes the design and construction of metal building systems in the low-rise, non-residential building marketplace. A non-profit trade organization, MBMA's headquarters is in Cleveland, Ohio. The organization consists of building system members, who are certified according to standards which have been set by the International Accreditation Service of the International Code Council, and associate members, who work in the metal building industry. MBMA has a General Manager, and it has a chairman and Board of Directors who are elected by members on an annual basis.
In structural engineering, a pre-engineered building (PEB) is designed by a PEB supplier or PEB manufacturer with a single design to be fabricated using various materials and methods to satisfy a wide range of structural and aesthetic design requirements. This is contrasted with a building built to a design that was created specifically for that building. Within some geographic industry sectors pre-engineered buildings are also called pre-engineered metal buildings (PEMB) or, as is becoming increasingly common due to the reduced amount of pre-engineering involved in custom computer-aided designs, simply engineered metal buildings (EMB).
Hybrid masonry is a new type of building system that uses engineered, reinforced masonry to brace frame structures. Typically, hybrid masonry is implemented with concrete masonry panels used to brace steel frame structures. The basic concept is to attach a reinforced concrete masonry panel to a structural steel frame such that some combination of gravity forces, story shears and overturning moments can be transferred to the masonry. The structural engineer can choose from three different types of hybrid masonry and two different reinforcement anchorage types. In conventional steel frame building systems, the vertical force resisting steel frame system is supported in the lateral direction by steel bracing or an equivalent system. When the architectural plans call for concrete masonry walls to be placed within the frame, extra labor is required to ensure the masonry fits around the steel frame. Usually, this placement does not take advantage of the structural properties of the masonry panels. In hybrid masonry, the masonry panels take the place of conventional steel bracing, utilizing the structural properties of reinforced concrete masonry walls.
Metal profile sheet systems are used to build efficient, reliable and cost-efficient envelopes of mostly commercial buildings. They have evolved from the single skin metal cladding often associated with agricultural buildings to multi-layer systems for industrial and leisure application.
The Patera Building prototype, a significant example of British high-tech architecture, was manufactured in Stoke-on-Trent in 1982 by Patera Products Ltd. In 1980, Michael Hopkins architects and Anthony Hunt Associates engineers were instructed by LIH (Properties) Ltd to design a relocatable building 216 square metres in size.