Cold Rolled Steel vs Structural Steel: What is best to use for my Shed?

If you are looking for a robust and long-lasting shed, you need to choose the right structural design and materials. One option for shed building is cold rolled steel, also known as rolled-formed steel.

While we don’t use cold rolled steel here at Alpine, we believe it is beneficial to know all of your options before investing in a new shed. That’s why, in this article, we explain what cold-rolled steel is, its pros and cons, and the best applications for this type of steel shed structure. 

We also share how structural steel is a more suitable alternative, particularly for larger structures and wider spans. 

What is cold-rolled steel?

Cold-rolled steel consists of high-tensile sheet metal that is rolled into sets to form an engineered shape. Cold rolled steel is generally only 1 to 2mm thick but the rolled profile increases the object’s strength. 

To help you decide if a cold-rolled steel frame shed is suitable for your needs, we’ve outlined the key pros and cons of cold-rolled steel below. 

Pros of cold-rolled steel sheds

• Light gauge steel.

• Lightweight design.

• Common with providers all around New Zealand.

• Suitable fit for small spans and light commercial builds.

Cons of cold-rolled steel sheds

• Higher risk of structural damage caused by a knock from machinery or forklift. 

• Rust quickly causes structural damage.

• Designs featuring knee and apex bracing are not birdproof.

• Knee and apex braces may protrude and lower the usable internal space.

• Not typically suitable for integrating gantry cranes.
  
  

When not to choose a cold rolled steel shed

Due to structural limitations, cold rolled steel may not be able to withstand the wind, rain, snow, and sea spray New Zealand experiences. While cold rolled steel sheds may be suitable for temporary solutions, a more durable option is structural steel and hot dip galvanised steel. 

Another reason not to choose cold-formed steel is when you need maximum storage capacity. With knee and apex braces protruding into the internal space, you may be limited in the equipment you can store inside, particularly when storing machinery or larger vehicles. What’s more, birds perched on these braces can cause significant damage to assets below.

Fortunately, hot dip galvanised structural steel sheds and timber pole sheds offer a solution. 

What is structural steel? 

Structural steel is widely renowned for its durability and strength. It is often 6-12mm thick and sometimes even thicker, compared to roll-form steel which is around 2-3mm thick. 

Structural steel buildings are made up of more steel than a typical roll-formed building, meaning they can cost more for the initial investment. However, this ensures a robust structure that can withstand the knocks, and often gets a longer consented lifespan - 50 years as opposed to some rolled steel buildings of 25 years. Key benefits of structural steel sheds include:

• Quick to install with bolted connections.

• Suited for large building spans.

• Design flexibility.

• Can support gantry cranes where required.

• Low lifetime cost of ownership and requires little maintenance.

Hot-dipped galvanised steel

Hot dipped galvanised steel is structural steel that has a thick, durable coating evenly applied to the surface. This coating provides exceptional protection against corrosion, making it a durable and cost-effective solution for many applications, including coastal environments. 

Hot-dipped galvanised steel is also extremely tough and abrasion-resistant, minimising damage incurred during handling, transportation, or installation. Once the steel span shed is built, it’s also incredibly low maintenance, reducing costly and time-consuming repairs.

Timber pole sheds

Timber pole sheds are constructed with timber framing, which is superior due to steel noise reduction, structural performance in extreme heat, and cost. Depending on the size of the shed, the poles are firmly concreted into the ground between 1.2m to 2.0m deep to prevent movement. 

When wiring for electricity and completing the internal fit out of your shed, timber is safer, most cost-effective, and easier to work with. You can simply fix features to the timber framing, including plywood lining, shelves, or hooks.

Learn more about the pros and cons of Timber pole sheds here. 

Alpine Buildings NZ

At Alpine Buildings, we supply a wide range of timber pole sheds with structural steel. Our steel is hot-dipped galvanised and can achieve wide clearspans, minimising the number of poles inside the shed and allowing our bird-proof system. Benefits of our sheds include: 

• Complete kitsets delivered for free

• Birdproof rafters and clearspan

• Fast lead times

• Pre-dried timber

• In-house design team

• Building consent

• Cost-effective timber framing

If you need a reliable pole shed that’s durable and practical, we’re here to help. Click below to find out what sets our sheds and services apart.