Every steel building has a primary frame designed to provide maximum stability for the local environment and the use to which the building will be put. Several framing systems have been developed, each appropriate to differing sizes and needs.
Tapered beam framing is one example of rigid framing.
What is meant by tapered beam framing?
Tapered beam framing is a rigid frame consisting of straight columns and tapered beam rafters. It is the primary frame or main support structure for a building. A tapered steel beam is a built up I-beam that is wider at one end than the other, giving a tapered appearance to the member.
The tapered rafter beams are assembled so that the small ends are adjoined at the mid-span, and the wide ends extend to the exterior walls to increase head space in the center. The wide ends can be installed in the center instead to provide better clearance on the sides of the building.
Tapered beams are also called wedge beams or slant beams. They can be used as columns in certain designs, including lean-tos and other special designs to maximize floor space.
How strong is tapered beam framing?
Tapered beams are made of high-strength steel that meets or exceeds ASTM A992 standards. The tapered shape provides a high stiffness-to-mass ratio for seismic and wind load stability.
The primary frame is further strengthened with the addition of the secondary frame and its bracing. When combined with girts and purlins, tapered beam framing provides the maximum amount of usable space.
Is tapered beam framing versatile?
Tapered beam framing is the best solution for clear span construction. Clear span construction provides a large open space without the obstruction of interior columns. Tapered beam framing is also appropriate for multi-span construction for buildings wider than 130 feet.
Tapered beam framing can be used to create offices, retail or other commercial space as well as warehouses up to 120 feet wide. Tapered rafter beams are paired with straight wall columns, simplifying the installation of straight interior walls.
A building constructed with tapered beam framing is easily divided with movable partitions and are easily reconfigured. Tapered beam framing can be gabled or single slope.
What factors determine whether tapered beam framing is the best primary framing for your project?
Besides size, you must consider other factors in your decision to use tapered beam framing.
- Roof slope - the nature of tapered beams lends itself to relatively low sloped roofs from 1/4:12 to 1:12.
- Do you need interior columns or do you prefer an unobstructed space?
- How do you plan to finish the interior?
- What type of roofing and wall materials will you use?
Tapered beam framing is also cost-effective since less material is required to manufacture the beam. This type of frame also provides uniform minimum depth columns.
How is tapered beam framing measured?
Tapered beam framing is measured from several different aspects.
- Frame width - the distance between the eave struts and the outside girt surfaces.
- Clear span - the distance between columns as measured from inside face to inside face.
- Eave height - the distance from the top of an eave strut to the column base plate.
- Clear height - the distance between the lowest structural point and the floor.
Your metal building consultant can assist you with determining the correct measurements for your project.
Why use tapered beam instead of another type of beam?
Tapered beam framing uses straight columns that provide maximum floor space and allow interior finishes to be installed quickly and easily. If you are planning a strip mall, tapered beam framing is appropriate for single slope construction, a common design for retail strips. Single slopes are also easily expanded at the sidewall.
Tapered beam framing with flat bottom rafters and straight columns easily accommodate monorails and underhung-carriage crane pathways for warehouses, manufacturing and other industrial uses.
Finally, since less steel is required to manufacture tapered beams, this type of framing is more cost-effective than using all straight members.
What stressors can tapered beam framing withstand?
With the high stiffness-to-mass ratio, tapered beam frames meet building codes for seismic and high wind lift stability. However, the frame is not so stiff that it cannot flex to withstand a certain amount of torsional or rotational pressure.
For which type(s) of construction is tapered beam most suitable?
Tapered beam framing is suitable for single and multi-span construction as well as single slope and gabled applications. Depending on the taper of the beam, you can design a low slope roof with a flat interior ceiling. A single slope tapered beam frame is also a handsome addition to expand an existing building.
Clear spans from 120 feet to 150 feet without interior columns can be built using tapered beam frame. If a wider building is required, you can still use tapered beam framing for multi-span construction of buildings up to 300 feet wide or more. It is also appropriate to use with cold-form purlins or open web joists.
Tapered beam framing is typically used for single-story buildings spanning 30 feet to 60 feet.
How can you obtain a tapered beam framing solution?
Tapered beam framing is available as a pre-engineered building system, which can be used in low-rise, agricultural, commercial, industrial and storage construction.
A pre-engineered building is delivered to your site with all primary and secondary frame members, fasteners, bracing and wall and roof panels. Every hole has been pre-punched, many of the fasteners are self-driving and may be concealed-type fasteners depending on the building design. Some parts may be pre-welded. Much of the building has been assembled and checked for fit before it leaves the manufacturer.
The tapered beams and the rest of the system are manufactured to exacting standards with tight quality assurance. The building is designed to comply with local and international building code.
Tapered beam framing is a highly versatile type of metal building frame that can be used for a wide variety of buildings. Tapered beam frames are especially well-suited to clear span construction from single span to multi-span designs. Tapered beam frames can be either single slope or gabled and tend to have low slopes of 1:12 at the most.
Tapered beams are commonly available and are more cost-effective than straight beams because less material is required to manufacture them. However, there is no loss of frame strength or rigidity when you build with tapered beams.