The Science of Shed Longevity
A shed is a big investment, so you want your money's worth out of it. The longer it lasts, the more value you extract.
How long your shed lasts isn’t a matter of luck. The materials used, the engineering, construction, foundations and maintenance all play a big part. If you’re building a Toowoomba shed or one anywhere in South East Queensland, all of those factors need to be spot on. That’s the only way your steel structure will be able to handle the harsh climate, year after year.
Today, we’re going to go over the science of shed longevity, tapping into what sheds that last for decades have in common.
BlueScope Steel
For us at Stockman Sheds, that means using only BlueScope Steel in the construction of our shed frames. This high tensile Australian steel boasts 450-500MPa of strength, whereas other standard steels come in at 250MPa. The structural integrity it provides is outstanding, while it’s superior corrosion protection provides long-term resistance.
BlueScope Steel is a consistently good product, which helps us in the planning of our sheds. We know exactly how it's going to behave, and can design our sheds accordingly. If the designs are accurate, the frame and components will go the distance.
Quality Shed Accessories
If your shed lasts for decades, you want high-quality fixtures and fittings that can keep up. At Stockman Sheds we prefer to use Australian products, because they’re tried and tested in our conditions. For roller doors, we rely on Steel-Line. For personal access doors, Larnec. For windows and sliding glass doors, Bradnams never let us down.
Materials Used
You’re going to get out of your shed what you put into your shed - raw materials and components are pivotal to lifespan.
Colorbond® Cladding
Your roof and cladding keep the weather out and everything inside your shed nice and secure. Colorbond® is a BlueScope Steel product that will do this year after year.
The strength of your walls and roof is determined by the BMT of the cladding material you use, or the Base Metal Thickness. This is the thickness of the steel without it’s coloured coating - ie the steel that carries load and resists bending.
A thicker BMT means a more resilient shed that is likely to resist fatigue, dents and damage. With Colorbond®, we can implement a BMT of 0.42mm. This is in accordance with Australian construction industry best practice, and drastically exceeds the 0.30mm BMT some manufacturers rely on.
Once coated, this increases to a TCT (Total Coated Thickness) of 0.47mm. This coating consists of multiple layers, including paint, primers and a metallic coating, which work to block moisture and oxygen and prevent corrosion.
Engineering and Construction
Strong materials are still going to require the correct engineering and construction if your shed is to enjoy a long and useful life. It’s about striking that balance of crafting the shed the owner wants without compromising on its durability. These are some of the engineering aspects we take into account.
Load Paths
Every force acting on a shed has to travel through the structure and into the ground. Wind hits the roof, moves into columns, then footings, and finally into the soil. That chain is called the load path.
If one part of the path is weaker than the rest, stress builds up there. Over time, that stress can result in movement, fatigue and damage.
A well-engineered shed will have the load spread out evenly without overloading a single part.
Wind Power
Wind can cause serious long-term damage in a shed - it pushes the walls inwards and lifts the roof upwards. In Australia, wind design is governed by the Australian Standard AS/NZS 1170.2, which calculates wind pressures based on location and terrain.
All SEQ sheds, in fact all sheds around the country, need to meet the design criteria of the wind zone they’re located in. When you comply with these standards, the shed is better equipped to deal with the wind conditions now and into the future.
Expert Construction
You’ve got robust raw materials, a stellar design and the right engineering - the shed still needs to be built right, though. The slab needs to be laid properly, the columns need to be straight, the bolts tightened and the bracing installed to perfection.
A small mistake might not show up at the time or cause instant failure, but it can add stress that builds over time. Years later, that shows up as sagging, cracking or doors that don’t line up.
Brackets and Connections
The connections in your shed take more stress than most people realise. Forces against the walls and roof all pass through the brackets and bolts. That makes them some of the hardest-working parts of the structure.
Bracket Thickness
A durable shed will make use of tough steel brackets engineered to deal with significant loads. At Stockman Sheds our brackets are 6mm thick and are made of hot-dipped galvanised steel. Some shed companies use 1.6mm zinc plates for their brackets - these will deform easily and allow more movement. Always check bracket strength when choosing a shed manufacturer.
The Foundation
All sheds need a strong foundation if they’re going to last for decades to come.
Soil Analysis
Soils behave differently and the same shed design will perform very differently depending on soil. Before design and construction, a full soil analysis should be undertaken so that the shed engineering can be adapted to the ground it’ll be built on.
Concrete Strength
A lot of shed companies get away with using 20-25MPa (Mega Pascal) concrete. We get far better results when it comes to durability when using 32MPa concrete. This is a higher-pressure material that’s extremely high-strength. It’s what you’ll find in bridges and roads - which makes it a tough foundation for a shed.
Slab Design
Effective design evenly spreads out the shed weight across the footings. The size, depth and spacing of piers is important - we like to have one under each column in the sheds we build at Stockman. Edge beams around the perimeter of the slab help support the walls and prevent cracking.
Drainage protects foundations
Poor drainage lets soil soften, swell or erode which can lead to movement and cracking over time. Long-life sheds manage water so it flows away from slabs and piers. Consistent moisture means consistent movement. Say you have more moisture in one corner of the shed - it will make the soil there swell and the slab heave. With good drainage, you get even shrinkage and swelling of the soil, which minimises slab heave.
Shed Maintenance
A good shed quietly gets on with it, but there are some maintenance tasks that can be undertaken to ensure you get the maximum years of usage out of it.
Annual Checks
Once a year, walk around and look at roof sheets, screws, flashings, gutters, doors, brackets and bolts. Early signs of rust, movement or loose fixings are easy to fix when they’re small.
Small Habits
Keep plants away from walls. Keep drains clear. Wash off heavy dust or grime. Fix small issues early. Over decades, those habits add years to a shed’s life.
What It All Adds Up To
Sheds that keep on delivering, year after year, are no accident. They come from:
Good materials like BlueScope steel and properly matched coatings
Engineering that handles wind and load properly
Foundations designed for the soil
Strong brackets and well-designed connections
Simple and regular maintenance
Remember, good sheds are built on solid science. If you’re building your shed in Toowoomba, or anywhere around Australia, getting the science right will be the difference between one that lasts for generations and one that gives up the ghost in a few years.
As always, get in touch with Stockman Sheds with all your shed-related questions.
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