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If you need a hangar, let’s design one together.
We make it easy!

Larry Stevens

Gable Symmetrical: A double slope building where the ridge of the roof is in the center of the building. This is the type of metal building that can be configured, priced, all through our online design system.

Gable Unsymmetrical: A double slope building where the ridge of the roof is off-center. This type of building requires a custom quote.

Single Slope: A sloping roof in one plane. The slope is from one sidewall to the opposite sidewall. This type of building requires a custom quote but we are adding this to our dealer’s online design system.

Lean-To: Ideally suited to give you that extra space you need alongside your building. The lean-to attaches at or below the eave of your building, and can provide shelter for a variety of uses, from just a covered area to a completely enclosed addition to your building. This type of addition requires a custom quote.

Hybrid Structures: Hybrid structures blend the advantages of metal building system construction with the conventional steel or wood members. Hybrid structures meet heavy loading requirements by providing the most effective design possible – the best of both worlds. The advantages include:

• Design flexibility
• Single source responsibility
• Fast, easy construction
• Cost effectiveness

The designs and engineering available allows virtually any requirement for hybrid structures, no matter how large or complex. When it comes to large, tough construction jobs, the hybrid building approach provides a cost conscious alternative.

Crane Buildings: With the use of metal building systems dominated by the manufacturing, industrial, and warehousing sector, building cranes as part of the structure has become an important element. We recognize the need to properly integrate the design of the metal building system with the building crane specifications. The building crane is a complex structural system consisting of the crane with trolley and hoist, cranes rails, crane runway beams, structural supports, stops, and bumpers.

The cranes typically found in metal building systems top running bridge cranes. Although there are many other types;

• Underhung
• Monorail
• Jib
• Stacker
• Gantry

We can provide each metal building and crane support system to meet the specific requirements of your project with either subs for rails for the crane to run on or point loads on the structure for different industrial uses, ie conveyers, chain lift.

Aviation Facilities: Aircraft hangars are individually engineered to meet specific requirements and are flexible enough to satisfy even the most complex aviation need. The steel aircraft storage hangars may be designed using gable symmetrical, gable unsymmetrical, or single slope structural systems. But for the easiest design it is best to place he hangar rood on the endwall parallel with an endwall frame to hang the stub columns from.

These cost effective, metal aircraft hangar designs have many advantages:

• Design flexibility
• Fast, easy construction
• Reduced maintenance costs
• Most important – we detail the hangar door engineering into the structure

The clearspan design provides column-free interiors for wide-open floor space and eave heights that can accommodate today’s larger aircrafts. The structures allow for a variety of door options including bi-fold, hydraulic one piece doors, bi-parting, and stack leaf designs.

By combining the metal building system with conventional exterior materials such as brick, stone, precast concrete, or glass, the structure can be aesthetically appealing while providing the perfect solution to aviation needs.

Construction Material Requirements

Consider some of the key factors that influence the selection of construction materials by the manufacturer, the designer, and the user.

STRENGTH is a very important factor.

AVAILABILITY the timing of materials influence its selection, cost of material, and final in-place cost.

WEIGHT and BULK becomes important from a handling and shipping standpoint.

DURABILITY of the finished product is measured in terms of its resistance to wear and destruction from all causes. Nothing much last longer then steel.

Materials must be capable of presenting a pleasing APPEARANCE.

Steel is used extensively in many segments of construction. The primary advantage of steel is its strength. The material, as it comes from the mills, has very exacting specifications, enabling engineers to design structures with a high degree of accuracy. In addition, steel is a plentiful and a well-accepted material. It has a high degree of workability because it can be cut, welded, shaped, and formed to meet a great variety of needs. Steel can also take a great deal of abuse and wear.

The greatest disadvantage of steel is that it will rust when exposed to the elements. This is prevented, however, by the application of protective coatings. At the factory they punch the holes and bend the pieces first then paint the pieces including inside the holes and edges. This provides a great advantage preventing rust.

Although steel will not burn, it is not classified as fireproof because it can become distorted, lose its structural strength, or even melt, depending on the intensity of the heat. Nevertheless, compared to many materials, steel offers a great deal of fire resistance due to the large amount of heat needed to cause any damage.

Fundamental Factors Affecting Building Design

Buildings provide shelter for persons and property. A building must have many desirable characteristics such as an attractive appearance, long life, flexibility of use, and economy. Protection though is one of the most important qualities in a building.

You might analyze this further and consider two kinds of protection.

1. Protection against forces or loads that may be exerted upon the building. Unless the structure can offer adequate resistance against various loading conditions, the safety of persons and the value of property are endangered. This is where sound design consideration must be given as to the strength of the metal building and particularly to the structural system.

2. Protection is protection against rain, wind, heat, and cold. Any of these can contribute to the discomfort of persons and cause a decrease in the value of contents. The degree of protection is determined by the weather tightness and thermal efficiency of a building. These things, of course, greatly influence the design of roofs and walls, also known as the covering system.

Design Loading

If you were to ask an engineer to design a prefabricated metal building of a certain size, he/she would first have to know what type and magnitude of the loads that would be imposed upon the building. Only with this basic information will he/she be able to design a building that will meet the prospective customer’s exact needs for loading conditions, it is important that you have a basic understanding of design loading.

A load is a force exerted upon a structure or one of its members. There are many different kinds of loads that must be taken into consideration in various situations, but only those that are of prime importance will be covered here.

Dead Load: The weight of the metal building system, such as roof, framing, and covering members.

Live Load : Any temporary load imposed on a building that is not wind load, snow load, seismic load, or dead load. A few examples of a live load are workers, equipment, and materials.

Snow Load : The vertical load induced by the weight of snow, assumed to act on the horizontal projection of the roof of the structure.

Ground Snow Load : Ground snow load is a calculation of a combination of slope roof snow and many other factors. Ground snow load is usually a higher value then roof snow load and two should be confused as the same.

(Note: Very wet snow 6″ deep is equal to one inch of water. One inch of water on a square foot of surface weighs five pounds.)

Wind Load: The forces imposed by the wind blowing from any direction. For a pre-engineered metal building the wind mph is translated into pounds per square foot and the converted load is allied to the building.

Seismic Load: The load(s) acting in any direction on a structural system due to the action of an earthquake.

Auxiliary Loads: All dynamic live loads such as cranes and material handling systems. This could also include point load for curbs or HVAC units for example.

Collateral Load : The weight of additional permanent materials, other than the weight of the metal building system, such as sprinklers, mechanical/electrical systems, and ceilings.

Resistance of Material to Forces

Loading has been defined as a force exerted on a building. Such forces are transmitted through joints and connections to individual parts or components. This eventually leads to a consideration of the properties of materials to resist forces in order to provide the engineer with a basis for subsequent design calculations.

Stress:The force acting on a member divided by its area.

Tension: Stresses acting away from each other that produce a uniform stretching of a member.

Compression: Stresses acting toward each other that causes a member to compress.

Shear: Stress that tends to keep two adjoining planes of a material from sliding on each other, under two equal and parallel forces acting in opposite directions.

Column Reactions

Any structure placed on a foundation causes a load to be imposed on that foundation. All buildings have these loads imposed by the columns on the foundation. These loads are called column reactions.

Column reactions are often expressed using the term “kip.” A kip is a commonly used engineering term for 1,000 pounds, derived from the contraction of the words “kilo” (1,000) and “pound”.

Framing structures exert a load on a foundation both vertically and horizontally. The vertical load is the result of the dead weight of the structure, and other loads such as snow on the roof, wind loads, crane loads, or seismic loads.

The horizontal load is the result of wind loads or seismic loads, and also produces the tendency of the base of rigid frame columns to spread apart under vertical load.

A third type of load arises from framing systems, which have fixed base columns. A streetlight or a flag poll is a common example of a fixed base column. When this type of column is subjected to wind loads, the foundation of such columns must be designed to resist the wind’s effort to overturn them. This overturning force is called a moment.

Engineers usually express the overturning moment as a “foot-kip”. As an example, assume that the wind load against the wall of the building creates an effective force of 2,000 pounds against the top of a 12′ column.

The resulting moment at the base would be an overturning force or moment of 24 -ft- kips (2,000 Pounds or 2 kips x 12 feet = 24 -ft- kips).

Load Transfer

Regardless of the type of load or where it is exerted on a rigid frame building, it is always transferred from part to part down to the foundation.

Assume, for example, a man standing on a roof of his metal building. His weight is directly on the panels, but the load is transmitted through the panels to the purlins, the closest purlins taking the greatest part of the load. The purlins transfer the load to the rafter, the rafter to the column, then the column to the foundation.

The load at the base of the column will be a vertical load and also a horizontal thrust or “side kick.” These horizontal thrusts can become very sizeable figures and must be taken into consideration when designing foundations for rigid frame buildings.

A wind load on the sidewall of the rigid frame structure may produce uplift on the main frame as well as horizontal thrusts.

The foundation must be designed to support not only vertical loads, but also the horizontal thrust.

Building Codes

Building codes are a set of minimum requirements for construction covering safety and serviceability. The safety requirements cover life, health, fire, and structural stability. Most areas have enforced codes governing construction in the community. They may be administered by a city, county, state, or by a combination of the three.

Building codes are necessary since their purpose is to benefit the public by helping eliminate unsafe design, poor construction practices, and unsightly buildings..

A community may originate and write its own codes, but generally they either adopt a recognized building code in its entirety, or modify it for its specific use.

International Building Code (IBC) Over the past several years the three national model building code bodies, SBCCI, BOCA, and ICBO have been working together to produce a single code to be used throughout the United States.

From a building design viewpoint, the IBC code has adopted new requirements for live, wind, snow, and seismic loads. The rules for applying and combining these loads are much more complex than in previous codes, and in many cases cause higher loads to be used for designing the building. This can result in higher costs for building foundations as well as for the pre engineered metal building structure.

There are new load maps in the code for wind, snow, and seismic loads. The wind load maps are based on 3-second gust wind loads, unlike the maps in the old codes that were based on sustained wind speeds. This means that the code specified wind speed for the whole country will be higher than before. Also, unlike some earlier codes, it is necessary to specify wind exposure categories and enclosure classifications.

The ground snow load maps in the new code is based on more recently accumulated data, but for most parts of the country the starting snow load values have not changed that much. However, there are new unbalanced snow load equations which drastically increase the roof snow load, especially for snow loads of 20 psf and greater.

The seismic provisions of the new code reflect the latest research for earthquake loads. The new seismic maps measures “Spectral Response Acceleration” for 0.2 and 1.0 seconds. This is a completely new approach to this problem. The IBC seismic equations and maps result in substantially higher imposed loads.

Over time, many areas have responded to unusual storms by increasing the base load to guard against future collapses. Many of the wind and snow load provisions of the new code were written in response to such events. Because of all these changes, you must make sure you confirm the exact loads and code with your local building department.

The snow provisions in the new code, for instance, may result in unbalanced loads because of the more than twice basic roof snow load, even with no high-low conditions. The minimum wind speed on the maps is now 85 mph, in lieu of the old 70 mph minimum that has been in effect for years.

Because of these changes, make sure to determine the values for the wind, snow, and seismic loads for a project only from the new maps. The majority of state and local jurisdictions seem to adopt newer codes and or change their values for any given area whenever they feel the need.

Codes are complicated and cover many phases of construction and differ from community to community. It is necessary that you become familiar with the codes that are applicable in your area. It is also advisable to discuss the code official’s interpretation of the codes. Interpretations of these codes can vary from official to official.
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Steel Design

Because of the various properties and characteristics of steel, many factors must be considered when designing both individual members and completed structures. Two organizations have published manuals that provide data and standards on which to base calculations for the design of steel:

AISC – The American Institute of Steel Construction was originated by steel fabricators and is generally concerned with hot rolled shapes and plates.

AISI – The American Iron and Steel Institute was originated by steel producers and is concerned with cold-formed steel structural members.

The manufacturer’s products, where applicable, are designed in accordance with AISI and AISC specifications. This is a mark of sound design and engineering practices, and contributes to the high quality of our products.

When customer service is needed we first discern the source of the error.  Because our buildings are completely engineered in house, we simply pull up the shop drawings and ship list from the server or we pull the job folder to ensure the factory manufactured to our specifications and that our design does not require further attention.  From there we devise a solution using the MBMA manual.  If the time comes that you need customer service, you’ll work with a single person in our office to reach a solution.
We at Rapidset Metal Buildings understand that a happy client is a returning client.  Our clients are based around the world which has given us a chance to travel, often just to make sure shipping, delivery, and construction goes smoothly.  Our clients return to us for all of their buildings because they know that Rapidset Metal Buildings provides an unparalleled product and unsurpassed customer service.
We do refer work, but experience has taught us to work mostly from established relationships.  If Rapidset Metal Buildings refers a client to you this means that you’ve purchased a number of buildings from us, that you know our system, and we’re confident in you as a builder, erector, or reseller.  Working by this philosophy has greatly reduced the number of calls from buyers who are dissatisfied with their builder.
This is why we say “come for the price, stay for the service”.

The view from a lift when building a metal building

The building system consists of primary framing members, secondary framing members, roof system, wall system, and accessories.

The prime objective of the Steel Building System is to provide a quality structure. Our buildings are available in a range of configurations – from the small, standard structures to maximum performance structures with creative architectural refinements to satisfy the spectrum of the owner’s requirements. The variety of building configurations and sizes offers many solutions to fulfill needs of the commercial, community, and industrial markets.

Standard versus Non-Standard

You will hear the word standard used many times in our business. It is misunderstood more than any other word. Certainly any manufacturer who designs and produces parts that must fit together to provide a completed product has a definite direction or “standard”, which is the base of normal application of the product. Consequently, standard items are considered to be those that are commonly manufactured on the production line and those that are purchased by customers.

However, if a situation arises involving something that is “nonstandard”, it is still possible and practical to meet that need in many cases. Our engineers believe nothing is impossible but variation from a standard often means extra work, expense, and time. Sometimes this is negligible, but at other times it might be quite involved.

Primary Framing System

Primary framing furnishes the main support of a building. A bearing frame (post and beam) and a main frame (rigid frame) are examples of primary framing. In this text, we will not only be talking about the main frame as a primary framing system, but also about secondary framing members, and bracing that join with the main frames to make up a complete structural system.

Roof Slope

Roof-Slope is defined as the tangent of the angle that a roof surface makes with the horizontal, usually expressed in units of vertical rise to 12 units of horizontal run.

The roof slope of a building is expressed as 1/2 : 12, 1:12, 4:12, etc. A 1:12 roof-slope rises 1 inch in every 12 inches measured horizontally from the side of the building across its width to the peak of the building. A 1 : 12 is what is provided with the Value Building System.

The Main Frame

The main frame (rigid frame) is the primary structural member of the building system. The main frame consists of columns and rafters. Columns are used in a vertical position on a building to transfer loads from main roof beams, trusses, or rafters to the foundations. Rafters are the main beams supporting the roof system.

Strictly speaking, a main frame is structurally stable because of the rigidity of its connections. The main frame members are connected in such a manner as to make the entire frame act as a single unit. Two common types of connections used to connect major parts of a main frame are diagonal and perpendicular.

Knee/Haunch Area of Main Frame

The knee/haunch is that area of the eave where the column connects to the roof rafter. The knee/haunch ties the members together rigidly and converts them into a single unit to carry all loads, vertical or lateral.

Notice that in the area of the knee/haunch, the main frame (rigid frame) is deepest in section, which makes it the strongest area of the frame.

This is required primarily because of the vertical load considerations, but at the same time it enables the frame to offer lateral strength. What does this mean? It means that the strength designed into the frame for vertical loads is also available to carry lateral loads, which might be caused by high winds, earthquake shock, etc.

Because the inside flange of the knee is in compression, a resulting thrust is produced at the inside corner, which is upward and outward. Stiffeners are used to counteract the resistant thrust. Stiffeners are usually extended to the outside flanges and also serve to stiffen the entire web. The haunch connection also serves as a stiffener. Main frames may be considered as arches in their action, in that they produced a horizontal thrust at their base or a tendency to kick outward. Under certain loading conditions, however, an inward thrust might be produced at the base. Main frames belong to a general class called continuous structures because the action and stress travel throughout the entire structure, since all joints are fixed in a structural sense. Because of this, engineers must analyze an entire main frame as a complete unit in itself, and not as an assembly of separate members.

Visualize a big hand grasping the roof rafter of a single main frame at the peak. The hand is alternately pushing down and pulling up on the frame. Since the member is a continuous structure, it is easy to see that the base of the two columns will tend to kick outward or inward, depending on the type of load being exerted.

These thrusts, however, are easily counteracted by a properly designed concrete foundation. We have used the expression “easily counteracted” purposely because a qualified engineer can design an adequate foundation using the reaction charts supplied by the manufacturer. There are many buildings, both over-designed and under-designed, in use today that have improper foundations simply because the person designing the foundation was either unqualified or did not refer to the reactions furnished by the manufacturer.

The building drawings include reaction charts with various loading conditions for standard main frames. Our pricing program produces preliminary mainframe column reactions as well. Make these charts available to your architects and engineers so that foundations will be priced properly and economically.

Main frames are normally connected to the foundation by using the appropriate anchor bolts in a configuration that is described as a pinned condition. This means that the loads transmitted to the foundation are vertical loads and horizontal loads.

Endwall Frames

Assume a building is 100′ long, consisting of four 25′ bays as shown above.

The main frames indicated by MF in the drawing above support a roof area of two half bays. The endwall frames indicated by EW, however, only support one half-bay of roof load.

From this you can readily see that the endwall frames need not be as strong as the main frames. It is for this reason that in addition to expandable main frame endwalls, we offer lighter non-expandable mainframe endwalls, or even lighter bearing frame endwalls, depending on your customer’s requirements.

The expandable main frame endwall is designed to support two half bays of roof load and can support an additional half bay in the future. The non-expandable main frame is designed to support one half bay of roof load and cannot support an additional half bay in the future. Main frame endwalls do not require any bracing and clear the endwall bays for large framed openings or open wall conditions.

Secondary Framing Members

Secondary framing members are those members that join the primary framing members together to form building bays and provide the means of supporting and attaching the walls and roof. Secondary framing members are:

• Eave Struts
• Purlins
• Girts
• Bracing

Eave Struts

The eave strut is a roughly cee-shaped cold-formed member and is located as illustrated below. Cold-forming is the process of using press brakes or rolling mills to shape steel into desired cross sections at room temperature.

The eave strut provides an attachment and bearing points for the end of the roof sheets and wall sheets. Eave struts are available in nominal depths of 8″, 10″, or 12″ to match the purlin depth. Eave struts are pre-punched at the factory for bolting to the main frames.

Purlins

A purlin is a secondary framing member that serves to support roof panels and transfer the roof loads to the rafters.

The purlin is zee shaped as shown below. Purlins are available in 8″, 10″, or 12″, depth, and are available in different gauges of steel 16, 14, 13, or 12 to meet various loading conditions.

The continuous purlin is a zee shaped cold-formed member 8″, 10″, or 12″, depth with a 50 degree outer lip to facilitate nesting. The purlins are lapped at each interior frame with the lap varying from 8″ to 60″ depending upon the conditions. Continuous purlins take into consideration the design advantage of continuous beams. The economy is based on using them on multiple bays where the overlapped splice of the purlin, continuous over the rafter, assists in supporting the load of the adjacent bay.

Girts

Girts are secondary framing members that run horizontally between main frame columns and between endwall columns. They are zee shaped members like purlins, also available in depths of 8″, 10″, or 12″, and gauges of 16, 14, 13, or 12.

Standard girt spacing is the first girt at 7′ 4″ above finish floor and a maximum of 6′ there after. This standard spacing fits doors, etc., utilizing optimal design. Other spacing is available to satisfy design criteria. A low girt option is available on request at 3′ 6″, which stiffens the wall section, and is standard in high wind conditions. For applications where a drilled pier foundation or isolated pad foundation is to be used, a base girt is available at ground level for fastening the bottom of the panel. Girts and purlins are pre-painted at the factory. The Manufacturer welds all girt attaching clips to the frames for easier and quicker erection.

Bypass girts attach to the outside flange of the columns creating a more efficient design. The girt is lapped at each frame and at the first interior frame from the endwall. Bypass girts are used to take into consideration the design advantages of continuous beams spanning from bay to bay.

Flush girts attach to the web of the columns, with the girt face in the same plane as the column face. Which provides greater interior clearance.

In addition to playing an important roll in the structural stability of the complete building system, girts also serve the important means of providing the framing for the attachment of wall covering.

Bracing

In addition to main frames, endwall frames, eave struts, girts, and purlins, the building system must have adequate bracing to make the system stable in a lengthwise direction. Bracing systems transfer wind loads from endwalls and sidewalls to the foundation. Wind bracing systems must include two types:

1. Longitudinal bracing, for wind on the endwall.
2. Transverse bracing, for wind on the building sidewall.

Requirements for bracing systems described on these pages are based on the specifications of applicable codes.

A variety of methods are available for providing bracing for wind on the building endwall. Bracing systems of this type serve a secondary purpose of squaring the building. In addition to the standard method – diaphragm action, alternatives include X-bracing (cable or rod), fixed base columns, portal frames, and wind bents attached to column When bracing must occur in bays where doors or other accessories are required, fixed based columns or portal frames should be used.

Bracing Methods:

Diaphragm Action

Diaphragm action utilizes the diaphragm resistance of the wall panels to transmit lateral wind or seismic forces to the foundation. Diaphragm action utilizes undisturbed sheeting, floor to roofline, and assumes all wall panels are installed correctly.

X-Bracing

When diaphragm action of the panels is inadequate or not allowed, the first alternative is to provide cable or rod bracing between columns. X-Bracing transfers longitudinal forces to the foundation.

Fixed Base Columns

If the openings in the wall are such that they do not allow for the use of X-Bracing, then fixed base columns may be used. A fixed base column is a column with special base plate condition, which allows wind load to be transferred to the foundation. Therefore, fixed base columns will induce a moment to the foundation, thus requiring a special foundation design.

Portal Frame

If neither X-Bracing nor fixed base columns are acceptable, a portal frame (wind bent) can be used. A portal frame is an I-shaped section of built up material consisting of two columns and a rafter, running parallel to the sidewall, and attached to the web of the sidewall columns. As a standard the portal frame usually does not induce a moment to the foundation.

Brace to Interior Main Frame

A method of bracing used for an open bearing frame endwall is to provide bracing in the roof of the end bay. In this case, the lateral forces on the endwall are transferred to the first interior main frame. The main frame is then designed to resist this additional lateral force.

Flange Braces or Purlin Bracing

Flange braces are structural members that attach purlins, girts, and eave struts to primary structural members (columns or rafters). Purlin bracing is an angle connecting the bottom flange of adjoining purlins to prevent purlin roll.

Flange braces are used to prevent the main frame from twisting or buckling laterally under the load. They are an essential structural part and must be installed properly at all locations. Flange braces can also be very useful as an erection aid to align the purlins and eave struts for easier and lower cost roof installation.

Structural Paint

All primary framing members are factory cleaned to remove loose dirt, grease, mill scale, etc. They are then painted with a red oxide primer. The purpose of this primer is to provide temporary protection of the steel members during transportation and erection. Touch up may be required after erection. Red oxide primer also provides a surface that is chemical and corrosion resistant. Therefore, it is not necessary to put an additional finish coat of paint on the framing members. However, if it is desired, finish paint may be applied over the red oxide in the field. However, consult with the paint supplier for the compatibility and proper preparation of steel before the application of any finish paint. It is also recommended that a test patch of the finish paint should be applied to test for compatibility.

Secondary framing members are pre-painted by a company specializing in coating of metal products with a baked on red primer. Due to the special coating required for roll forming these members, they can be difficult to repaint.

Galvanized Steel

For over 140 years, galvanizing has had a proven history of commercial success as a method of corrosion protection in a myriad of applications. Galvanizing can be found in almost every major application and industry where iron or steel is used. The utilities, chemical process, pulp and paper, automotive, agricultural, and transportation industries, to name just a few, have historically made extensive use of galvanizing for corrosion control.

All of our buildings are also available in galvanized steel as a special option. Two types of galvanized material are used:

• Hot Dip Galvanizing
• Pre-Galvanized

Hot dip galvanizing is the process of applying a zinc coating to fabricated iron or steel material by immersing the material in a bath consisting primarily of molten zinc. The Manufacturer sends the fabricated material, such as, primary and secondary framing members, to the galvanizers.

Pre-Galvanized material is used for secondary members only. The pre-galvanized material used is of 55 grade and adheres to ASTM A653 specifications. The coil of pre-galvanized material is delivered to the Manufacturer and then the pre-galvanized secondary members are fabricated.

Clearspan Buildings

Clearspan buildings allow for the maximum use of interior space, which is particularly important in manufacturing plants, warehouses, offices, and retail stores where uninterrupted space is required. Size flexibility also pays off outside where optimum land use is an equally important consideration.

Virtually every symmetrical, unsymmetrical, and single slope building size and shape is possible as a standard product. Inside the clearspan building you have almost total flexibility in determining the height, width, and roof slope you want: building widths from 20′ – 150′; eave heights from 10′ – 30′; and roof slopes from 1:12 to 4:12. Building widths of 80′ or less are available with the option of straight columns instead of tapered columns.

Lean-tos are available for future expansion or additional space. A lean-to can be designed to match the eave height and roof slopes of the clearspan building if the building was originally designed to take on the loading of an additional lean-to load. Lean-tos are available in widths from 8′ – 60′, eave heights from 8′ – 30′, and roof slopes from 1/2:12 to 4:12.

Modular Buildings

A modular building (with interior columns) is specially designed for large buildings such as manufacturing plants, warehouses, truck terminals, and retail stores. Interior columns are either built up ‘H’ columns or pipe columns. ‘H’ columns are mandatory in a building with a top running crane. Modular buildings combine the proven practicality of a rigid frame with almost unlimited size flexibility.

With a building that is 100′ wide or less, the building can be designed with both clearspan frames and modular frames. This could serve the benefit of having a portion of the building with an unobstructed floor area while maintaining the cost savings of a modular building.

Modular buildings are also possible in any symmetrical, unsymmetrical, and single slope building size and shape as a standard product offering. Inside the modular building there is almost total flexibility in determining the height, width, and roof slope: building widths from 40′ – 500′; eave heights from 10′ – 30′; roof slopes from .25:12 to 4:12; and interior module spacing from 20′ to 100′. Modules are defined as the space between interior columns. THE STANDARD BUILDING is limited to 8 interior modules but more modules are available on request. Building widths of 40′ – 80′ are available with the option of straight columns instead of tapered columns. Lean-tos are also available for future expansion or additional space if the original main structure had been designed to support the additional load of a lean-to.

Lean-to

The lean-to is ideally suited to give that extra space needed alongside the building. The lean-to ties in at or below the eave of the building and can provide a variety of uses, from just a covered area to a completely enclosed addition to your building. A lean-to structure has only one slope and depends upon another structure for partial support. A lean-to can be located at eave or below eave of the supporting structure.

A lean-to is limited to 60′ wide as standard and only has a straight column at the low side and a rafter. The rafter attaches to the supporting structure’s column. Therefore, it is imperative that the bay spacing of a lean-to equals the bay spacing of the supporting structure.

Endwall guidelines for Lean-tos:

1. A lean-to with a bearing frame endwall may be attached to buildings having a bearing frame, an expandable main frame, or a non-expandable main frame endwall.
2. When the lean-to does not extend the full length of the main building and begins or ends at an interior main frame, the bearing frame endwall is the standard condition but also could be a main frame endwall if necessary.
3. If an expandable or non-expandable main frame endwall is used on both the lean-to and the main building the endwall may be completely open.

Endwall Types

Endwalls are available in three basic types:

• Expandable Main Frame
• Non-Expandable Main Frame
• Bearing Frame

Expandable Main Frames

The expandable main frame endwall is a combination of the standard main frame with endwall columns. The endwall columns do not support the rafter but serve only as columns for attachment of endwall girts and transmit the wind load into the foundation and structural frame.

The expandable main frame’s largest advantage is that it provides for easy expansion. Since it is a main frame it will carry the design load of a full bay, and it can remain in-place if the building is expanded.

Non-Expandable Main Frames

The non-expandable main frame endwall is still a main frame with endwall columns, but cannot be used for future expansion. The non-expandable frame can only carry the design load of one half bay.

Both the Expandable and Non-Expandable main frame endwalls provide for more flexibility and ease in locating large framed openings or entrance doors. Locate the openings by simply adjusting the endwall columns spacing. Also, the main frame endwalls do not require any form of bracing, therefore, X-bracing or portal frames will not interfere with large openings.

Bearing Frames

A bearing frame (post and beam endwall) is our standard endwall condition. The endwall columns are generally made of cee channel and at times can be back to back cee channel. The bearing frame is designed to support only one half bay of roof load, and cannot be used to expand the building in the future.

The endwall columns support the channel rafter and also serve as columns for attachment of the endwall girts and transmit wind load into the foundation and structural system. Bearing Frame Endwalls also require a form of bracing, whether it be X-bracing, portal frames, or diaphragm action.

The use of a bearing frame endwall is a matter of economy. You will usually find the prices of the bearing frame endwalls to be less than one half the cost of the expandable main frame endwalls.

Endwall Cost Considerations

It is important to recognize that the different types of endwalls can be interchanged to offer advantages in specific applications.

The expandable clearspan main frame endwall can provide an entirely open endwall up to 150′ wide. This could be the answer to a covered truck dock across the end of the building; or, total flexibility in placement of framed openings.

It is also possible to interchange the interior modular main frames comprised of different modular spacing. For example:

The 120′ wide building could have 3 – 40′ wide modules or 2 – 60′ wide modules. By interchanging some 60′ module frames within the structural system we can retain the lower cost of the interior columns yet provide larger unobstructed areas.

Also, using the 3 – 40′ modular main frame endwall in place of the 2 – 60′ module spacing, you would be able to place an overhead door in the center of the endwall without difficulty.

Many times the ability to interchange frames and endwalls can bring about cost reductions, which will amount to several thousands of dollars. These can be very important savings if you are working against competition or a low budget.

Airplane Hangar being built with a Stormy Sky

I was the erector not the GC on this building. I arrived with a slab and an unloaded building ready to go. The GC was in Louisiana and took the prints with him. SteelBuildingSupplier was very helpful in supplying us with new prints for our Rapidset building. We began mid summer and couldn’t have picked a better day. 8:00am, 65°, a light breeze, and not a cloud in sight. With the boom forklift we rented we had the Columns up with the girts and cable braces before lunch. As we bolted the rafters together at their eaves and began lifting them into place, the sky began to fill with clouds. It wasn’t until we had bolted one side of the second set of rafters that the wind began picking up. The weather worsened and we scrambled to bolt the other side and a couple purlins for support. We watched from another hangar on the property as Mother Nature tested our construction. As the wind picked up our under-supported rafters waved violently. We decided to raise the scissor lift against the underside of one of the rafters for support. Happily, I did not draw the short straw, and enjoyed watching as one of our guys drove a scissor lift at 1mph through the hail and successfully braced our building. The property owner had warned us of the unforecast storms that sneak up in Brighton, CO. I suppose the fact that it happened on Day One should have forewarned me of what was to come..
The next morning we began by bolting the rest of the purlins in that first bay, just in case the weather turned again. It was hot and windy that day but we were glad to see the ground dry up before we fired up the forklift. Day two was without incident and we had the endwall and third bay standing and braced by quitting time.
The home owner, a commercial pilot, was nice enough to allow us use of his house while he was away. He arrived at home that third day to find us sitting in his old hangar watching the rain. To say he was pleased with the work we had done so far was an understatement. The building sat on his property for four months before construction began. He was less than satisfied by the GCs performance, especially because he was told the project would take about two months from start to finish. After reviewing the radar maps of the weather system effecting us and attempting to explain several weather phenomena at work he told us the weather would not be clearing up anytime soon and treated my whole team to lunch, a movie, and dinner in the nearby town.
By the end of the week we had finished the red iron and frame of the hangar door. Admittedly, this was my first hangar. 99% of erecting a hangar is the same as any Rapidset building, but the thought of being responsible for this incredibly heavy door rising above people and hundreds of thousands of dollars worth of aircraft made me very nervous. The frame arrived from Schweiss in two pieces which, after being positioned, took only minutes to assemble. The forklift raised it into place and we bolted in the hinges at the top, simple enough. Given the unpredictable weather, we lashed the sides of the frame to the columns it rides on.
The second week was spent getting the hangar ready for insulation and sheeting. We bolted in the walk doors, framed openings, and the welder came out to weld on the brackets for the “auto closer” for the Schweiss door as well as the hinges.
The insulation and wall sheeting began going up the third week. Intermittent wind made for a particularly slow and frustrating experience. Twice, a gust of wind ripped off our strip of insulation before we could get the sheeting over it. We found that a pair of Vice-Grip clamps worked well at holding the top of the insulation in place. The end of the week arrived with another storm.  Once again not forecast and once again catching us off guard. We were on the verge of finishing the sheeting on the main walls when it hit us. The site was pelted with golf ball sized hail and high winds. We watched as a vortex passed overhead. The tornado touched down just a mile away. We watched news reports of the tornado and its destruction. The town nearby received six inches of hail. The news showed people shoveling driveways in shorts and t-shirts. Another nearby town was bombarded with baseball to grapefruit sized hail which resulted in many “Hail Sales” at car dealerships across central Colorado.
Damage at our site was minimal. The insulation we were unable to cover in time was torn loose and relocated to several trees in the neighbor’s yard.  After the storm passed we hung it from a purlin and it was completely dry a couple days later.
The next week’s weather was hot and humid. The problems that week were courtesy of the boom lift we had rented to help with the sheeting. When the first boom lift arrived on site it never even left the truck. The rental company couldn’t get it started so they promptly delivered another one to the site. A few days later this lift started to die. We had a couple guys suspended twenty feet in the air and the engine stopped and the boom controls didn’t function even in battery mode. The rental company told us the problem was probably due to an overheating hydraulic pump and to put a sprinkler in the engine compartment and let that slowly run as we worked. Skeptically I did just that and it seemed to do the trick because it died less frequently and took less time to get it going again when it did die.
We had a string of still and dry days leading up to working on the roof. So we made the poor decision to roll out the first two rolls of insulation over the roof before sheeting it. It wasn’t thirty seconds after we unrolled the second roll of insulation over the roof that a gust of wind came. I swear it was the only wind all day and it came just to blow our insulation to the ground. We continued on only rolling out the insulation we could immediately cover and the rest of the roof sheeting went smoothly.  The owner was afraid the insulation would begin to sag in the years to come and had us install steel strapping over the purlins every two feet. Although it was incredibly tedious and probably decreased the R value of the insulation, it made for a very smooth looking finish inside.
I began assembling the rest of the components on the Schweiss Bi-fold door while the rest of the guys worked on. The most complicated part of finishing the door was fixing the damage done by the GC when he unloaded it. A piece of tubing in the center was badly bent and took quite a bit of work to bend back into place. The straps were easy to install and properly tension. The motor bolted up perfectly, wiring it into the control box was straight forward. I’m pretty sure I didn’t breath the first time I hit the button to raise the door. My heart stopped when the roller on the door bounced over a weld, but all went as it should and I ground down that weld as soon as door was back down. The wind brace didn’t fully pull in the door the first time but after adding a bit more tension it worked wonderfully. Positioning the limit switches in the motor control box was very simple also… Raise the door to the height you want it to stop at and set that one, lower the door until the “auto-lock” engages and set the bottom one. Shortly after we were hit by the final storm on the job. Everyone but me had left for lunch when the site was hit by a micro-burst. Pieces of sheeting where violently thrown around the site. One sheet, right through the fiberglass door of an old hangar. The winds damaged many houses and hangars in the airpark but the Rapidset Hangar was unscathed.
The owner moved his planes in while we trimmed out the building and installed the windows. The electrician still had not run the conduit for the lights and door so I advised him to wait but in the end no damage was done to the planes. We finished the trim out late one night and so stayed one final night in the owners home. The next morning he woke all of us at 6:00am to celebrate his new hangar with a flight through the mountains just west of Denver. The perfect way to finish this job wrought with troubles… on a high note.