Corrugated iron has been part of the construction site and used in farm structures, industrial sheds for decades, and recently, as modern extensions to homes. Its unique profile delivers a balance of lightweight, strong, and ease of installation attributes, as well as low upkeep, which makes corrugated iron an ideal option for roofing and walling.
Some basic knowledge of its properties and the type of manufacture may assist the builder or owner in choosing suitable materials for a particular project. This blog discusses the practical advantages, important considerations, and relevance that still apply to corrugated iron in construction work across all scales.
What is Corrugated Iron?
Corrugated iron is made by cold-rolling thin sheets of mild steel into parallel ridges and grooves, enhancing their bending strength and flexural stiffness. This allows the material to span longer distances with fewer supports.
Typically, galvanised through a hot-dip process, a zinc coating is applied to protect the iron from corrosion caused by moisture and weather. This increases durability and extends the material’s lifespan.
With its strength-to-weight ratio, corrugated iron is cost-effective, durable, and ideal for roofing, cladding, and industrial use, offering long-lasting performance and low maintenance.
Properties of Corrugated Iron
Corrugated iron’s combined practical properties contribute to its continued use in a wide range of construction applications.
- Corrugated Profile: Its structural stiffness enables the sheet to expand greater distances with less support.
- Lightweight: Easy to move, handle, and install, resulting in a lower overall dead load.
- Corrosion-resistant Steel: A galvanisation coating provides resistance to rust and degradation through weathering, resulting in a longer service life.
- Workable: Sheets can be cut, shaped, and lapped to suit different roof pitches and wall situations.
- Weather performance: Steep pitch and ability to shed rainwater, carry wind loads, and have weather exposure due to profile.
- Thermal reflectivity: The metallic surface allows for solar reflection, aiding in heat deflection and regulating ambient temperatures.
- Versatile: Roofing and cladding material that can be applied to residential, commercial, and industrial buildings.
Due to these properties, corrugated iron is used in a wide range of industries.
How is Corrugated Iron Manufactured?
1. Raw Material Preparation: The process begins with mild steel coils, which are cleaned to remove any impurities, ensuring a smooth surface for the next steps.
2. Rolling: The clean coils are passed through rolling mills to create thin, flat strips. The material is reduced to a precise thickness, ensuring uniformity for the corrugation process.
3. Corrugation: This is the most crucial step, where specialty rollers are used to press the flat metal sheets into wavy corrugated patterns. The corrugations increase the structural rigidity and flexural strength, allowing the iron to span greater distances with fewer supports.
4. Galvanisation: In this phase, the corrugated sheets are dipped into molten zinc through the hot-dip process. This galvanisation provides corrosion resistance, protecting the metal from rust and ensuring its durability when exposed to weathering and moisture.
5. Coating and Finishing: The sheets may undergo additional coating or finishing processes to enhance appearance or provide extra protection against environmental elements.
6. Cutting and Sizing: After the corrugation and finishing processes, the sheets are cut to the desired size for transport and final use in construction projects.
7. Bundling and Transporting: Finally, the sheets are bundled and transported to suppliers or retailers for distribution.
The entire process ensures that the final product is durable, strong, and ready for construction.
Advantages and Disadvantages of Corrugated Iron
As a building material, corrugated iron has its advantages and disadvantages that must be considered before use.
Advantages
- Relatively convenient to transport, handle, and install, resulting in lower labour and structural support costs.
- The corrugated shape provides more support and ability to withstand weight or impacts.
- When coated or galvanised, corrugated iron is relatively resistant to rust and the effects of the weather.
- Generally less expensive than many other materials for roofing or cladding, making it more feasible for covering larger areas.
- It can be used for numerous applications, from roofing to wall cladding to fences and sheds.
- Large sheets cover a great deal of area effortlessly and expedite time on site for construction.
Disadvantages
- A noise hazard can arise (or be intensified) if there is insufficient insulation.
- It’s not likely a long-term building material; it can rust eventually (especially if you live in a coastal area) if the corrosion-resistant coating is compromised over time.
- It could add heat gain or loss if not properly insulated.
- Some users find the industrial look not suitable for some styles of residential design.
Application of Corrugated Iron
Corrugated iron is commonly used in the construction industry and offers architects and builders a functional and flexible option.
1. Roofing: Buildings such as homes, businesses, and factories are sheltered by corrugated iron sheets.
2. Cladding and siding: It can give a building a more modern, industrial aesthetic look. It may also be used on external walls for a new building or renovation project.
3. Fencing and enclosures: A strong and inexpensive option, and hence is frequently chosen for fences, boundary wall construction, and enclosures for security and privacy, while remaining clean and also contemporary.
4. Structural Elements: May also be used in a structural role, as part of the framework of a shed, temporary building, or lightweight structure, to provide additional rigidity and support.
Cost of Corrugated Iron
Agricultural, commercial, and industrial buildings can be roofed or clad with corrugated iron at an affordable price. The base material cost typically ranges from ₹40 to ₹100 per square foot, depending on the sheet thickness, galvanisation quality, and any additional coatings or colour finishes.
Also, because it is lightweight, it reduces sales and transportation costs (over larger volume orders, which saves transport and installation costs on commercial projects).
Maintenance and Longevity
When installed and maintained properly, corrugated iron has a long service life. The galvanised and coated sheets resist a wide range of weather conditions with timely maintenance.
Frequent checking for rusting, loose fasteners, or minor damages allows one to maintain the sheets. Keeping the surface clear of debris and water prevents corrosion. Repainting or applying a protective coating when a necessity arises can lengthen the life of the sheets, especially in coastal or humid conditions.
With adequate care and proper repairs, corrugated iron can act as a protective layer on structures for decades, making it worthy enough to be proposed as a choice for several building applications.
Expected Service Life in Different Conditions,
- Moderate Climate: 40–50 years with basic maintenance.
- Urban Areas: 30–40 years with regular cleaning to remove pollutants.
- Coastal Regions: 20–30 years with frequent inspections and anti-corrosion coatings
- Industrial Zones: 25–35 years with regular maintenance to manage exposure to chemicals or fumes.
Conclusion
Being more durable and cost-friendly, corrugated iron has remained a suitable material for different construction purposes. Its applications are so versatile that it can be used in rural buildings, industrial sheds, and residential or commercial buildings.
People who understand its manufacture, characteristics, and maintenance methods are always able to derive good results from their projects if this material is used. If used well, corrugated iron is an excellent candidate for durability and maximum returns.