What is a wide span shed?

If you’re planning to build a new shed, you may have heard the terms ‘wide span’, ‘portal-frame’ or ‘clear span’. As industry experts, we often get asked about these terms and whether they are worth factoring into a large-scale shed design. 

In this article, we explain what wide span sheds are, how they differ from other shed designs, and the best applications to use them. Whatever your needs, find all the advantages of wide span sheds below.

What is a wide-span shed?

A wide span shed, also known as a clear span shed, is a large structural frame consisting of two columns and a rafter spanning between with no centre supports. This self-supporting design is ideal for any application requiring maximum internal space, including:

Farm sheds

With no posts or walls inside a clear span farm shed, it’s easy to manoeuvre vehicles in and out and operate your farm equipment. For maximum efficiency, consider the advantages of a drive-through machinery shed. What’s more, clear span farm sheds are adaptable for storage which is critical for your ever-changing farm operations. 

Grain sheds

With no internal supports, a clear span grain shed is easier to navigate. With no walls or posts to avoid, you can easily access your grain with large machinery, speeding up your operations. 

Commercial and industrial buildings

If you need a large commercial or industrial shed, a clear span design offers flexibility. Not only is it easy to arrange equipment and manoeuvre machinery, but it also allows you to alter your setup as your needs change. 

Aircraft hangars

A wide span aircraft hangar offers easy access for all shapes and sizes. For example, ABC Sheds uses open web trusses to build sheds up to 60m clear span, accommodating anything from an Ultralight to a B52 (56 metre wingspan)! 

Large clear span sheds

To achieve maximum strength and durability in a clear span shed, there are several engineering requirements and design techniques to use – especially for large-scale sheds. We’ve outlined these details below. 

Hot-dip galvanised steel

Due to its increased longevity and added rust protection, hot-dip galvanised steel is the most effective material for wide span sheds. The zinc coating makes galvanised steel 2.5 times thicker than alternative steel coatings, preventing oxidation and corrosion. 

Additionally, it also gives a tidy appearance and is the highest-performing coating in coastal environments. At ABC Sheds, we use Australian-sourced steel for the most effective protection against our harsh weather conditions.

In addition to the galvanised coating, structural steel framing also offers maximum design flexibility, allowing you to create a wide range of styles and sizes. It can be easily cut, welded, formed to meet your exact requirements, and incorporate additional features, such as:

• Windows
• Slider doors
• Roller doors
• Ventilation systems
• Personal access (PA) doors
• Mezzanine floors 

RHS strength

Rectangular Hollow Sections, or RHS, are cold-formed hollow steel sections offering high strength and durability. ABC Sheds hot dip our trusses, after fabrication. Be wary of shed companies that quote wording such as 'duragal', 'pre-gal', 'galtube', 'galforce' or 'in-line galvanised' RHS. This DOES NOT refer to 'hot dip galvanising' and is completed before welding and is significantly thinner (100g/m2) than hot dip galvanising (300g/m2). ABC Sheds use RHS to form a truss rafter. Trusses are essentially a beam with all the unnecessary parts removed allowing for a much lighter alternative to a traditional UB rafter resulting in reduced deflection and far greater cost efficiencies, often saving our customers 10-15% on material costs.

Wind ratings

In Australia, there are four wind regions dictating the design requirements for large structures. Depending on the average wind speed in your area, your shed design will need to meet the relevant wind rating. 

For example, Wind Region D, located on the far west coast, has an Ultimate Design Wind speed of 316.8km/h. On the other end of the scale, Wind Region A, consisting of internal land and the southern coast, has an Ultimate Design Wind speed of 147.6km/h. To ensure your shed meets local regulations, speak with our experts today. 

Universal beams

A universal beam is a load-bearing beam that is virtually impossible to bend, buckle, or bow. Even if you knock them with your machinery, these beams are built to withstand the pressure. 

At ABC Sheds, we only use structural steel universal beams for our columns to carry the majority of the shed’s weight. What’s more, the beams are hot-dipped galvanised for ultimate longevity.

Simple erection

When it comes to building a new shed, the construction process has a significant impact on the overall cost and project timeline. When erecting your ABC Shed, there’s no need to brace the frame because the structure is self-supporting. With pre-drilled holes, all the bolts provided, and clear instructions, the whole process is quick and easy. 

Built to last

The harsh Australian weather conditions and industrial operations in your shed will impact its lifespan so you need a shed that will stand the test of time. Not only should the materials be durable and strong, but the engineering must be reliable. Every shed is engineered on its own merit to site specific conditions. Be very wary of shed companies that quote certified engineering as an optional 'extra'

At ABC Sheds, our hot-dipped galvanised columns are made from Australian-sourced steel and bolted on to the concrete foundations. Our frames are approximately 6 times heavier than a purlin frame, meaning they’re here to stay no matter what cyclones, wind, or snow come your way. 

Shed span 

So you might be wondering what the possible sizes are for clear span sheds. While this is dependent on your location and operations, our frames can be designed with a 12-metre span right up to a 60-metre span. 

These specifications are subject to variation so be sure to specify any requirements with our team. We can customise your shed to meet your unique operations and storage needs – just get in touch to see what we can do. 

Here at ABC Sheds, our clear span shed designs all include a hot-dipped galvanised structural steel frame and a 25-year guarantee. Our custom designs are built to exceed Australian building standards, giving you the ultimate peace of mind that your shed will serve your needs for decades to come. 

If you want to learn more about our wide span shed designs and specifications, find everything you need to know in our full shed brochure.