When designing or investing in a large construction project, ensuring long-term durability and minimising maintenance costs are critical factors. One of the fundamental choices in construction materials is selecting the right type of fasteners. The specification of the fastener, despite being a small component, is critical to the performance of the roofing and cladding system. While carbon steel fasteners have been widely used, they present significant drawbacks that can lead to costly maintenance and structural issues over time.
Stainless steel fasteners, particularly self-drilling variants, offer a superior alternative due to their corrosion resistance and longevity. Here’s why stainless steel fasteners should be your first choice over carbon steel fasteners.
The Problem with Carbon Steel Fasteners
Traditional carbon steel fasteners are prone to corrosion and rust, which can compromise the structural integrity of a building. Additional coatings have to be applied to prolong their life. These coatings tend to be easily damaged leading to corrosion (rusting) of the core steel. Over time, rust can cause fasteners to lose integrity, leading to leaks and air ingress, which can reduce the energy efficiency of the building. As current building regulations emphasise energy efficiency, ensuring airtight, well-sealed construction is crucial.
Moreover, corroded fasteners may stain exterior and/or interior surfaces, creating an unsightly appearance and increasing maintenance costs. Replacing rusted fasteners can be labour-intensive and expensive, making carbon steel a less favourable option for long-term performance.
The Science Behind Stainless Steel Fasteners
Stainless steel fasteners provide a much longer service life than carbon steel fasteners due to their alloy composition. The key components are chromium and nickel which form an inert oxide layer on the surface, preventing corrosion and ensuring durability. This protective layer allows stainless steel fasteners to withstand harsh environmental conditions, making them ideal for construction projects exposed to moisture, pollutants, and varying temperatures.
However, stainless steel is naturally softer than hardened carbon steel, which presents challenges when drilling into hard, i.e. high tensile, materials such as the steel substructure of a portal framed building. To overcome this, the drill point and lead-in threads of stainless steel self-drilling fasteners are carbon steel that is welded in place. A coating is then applied to act as a lubricant making installation consistent and efficient whilst preserving the integrity of the stainless steel body.
Long-Term Performance and Warranty Benefits
One of the key advantages of using stainless steel fasteners is their durability, with an in excess of 25-year Life Expectancy. Whether the project is large or small, problems with building integrity, be that water ingress, air leakage or worse, structural failure can cause major issues for the occupiers and owners. Stainless steel fasteners provide this reliability, allowing businesses to focus on operations without concerns about integrity.
Furthermore, stainless steel fasteners form a key part of system warranties, providing additional peace of mind to developers and investors. A warranted product ensures compliance with building regulations and long-term structural performance, reducing and managing risk..
Choosing the Right Grade: A2-304 Stainless
For the vast majority of metal roof and wall applications, A2-304 stainless steel (EN 1:4301 wire) is the most cost-effective and durable option when longer-term performance of 25 years plus is required. It performs well in almost all environments, including inland and coastal regions. Some suppliers may promote A4-316 stainless steel, often referred to as marine-grade stainless steel, due to its higher nickel, chromium, and molybdenum content.
Some suppliers provide the option of A4-316 stainless steel product alongside the A2-304 grade as both are designated as suitable for use in all environments as listed in BS EN 1993-1-3:2006 Durability of fasteners Classification of environment C1-C5. However it should be noted the A4 316 grade whilst also suitable, has a 20% increase in costs. While A4-316 provides increased corrosion resistance, it is only necessary for extreme environments.
It’s important to note that when selecting fasteners for swimming pool environments, neither 304 nor 316 grade stainless steel is suitable. The chlorine-rich atmosphere can cause what is known as ‘chlorine-induced stress corrosion,’ which presents a safety risk, particularly in safety-critical or structural applications. In such cases, higher-grade stainless steels with a minimum 7% Molybdenum—such as EN 1.4547 or EN 1.4529 wire should be used.
Conclusion
When planning your next construction project, stainless steel fasteners provide unmatched longevity, corrosion resistance, and overall structural reliability. Unlike carbon steel fasteners, which corrode and weaken over time, stainless steel fasteners maintain their integrity for decades, ensuring airtight, energy-efficient buildings with minimal maintenance. Choosing the right grade, A2-304 stainless steel (EN 1.4301) for “standard” construction you get the best value for your investment.
For more information on our high-performance, ETA-assessed, stainless steel fasteners, get in touch with one of our technical experts at Fixing Point, who can provide tailored solutions to meet your construction needs.
The Problem with Carbon Steel Fasteners
Traditional carbon steel fasteners are prone to corrosion and rust, which can compromise the structural integrity of a building. Additional coatings have to be applied to prolong their life. These coatings tend to be easily damaged leading to corrosion (rusting) of the core steel. Over time, rust can cause fasteners to lose integrity, leading to leaks and air ingress, which can reduce the energy efficiency of the building. As current building regulations emphasise energy efficiency, ensuring airtight, well-sealed construction is crucial.
Moreover, corroded fasteners may stain exterior and/or interior surfaces, creating an unsightly appearance and increasing maintenance costs. Replacing rusted fasteners can be labour-intensive and expensive, making carbon steel a less favourable option for long-term performance.
The Science Behind Stainless Steel Fasteners
Stainless steel fasteners provide a much longer service life than carbon steel fasteners due to their alloy composition. The key components are chromium and nickel which form an inert oxide layer on the surface, preventing corrosion and ensuring durability. This protective layer allows stainless steel fasteners to withstand harsh environmental conditions, making them ideal for construction projects exposed to moisture, pollutants, and varying temperatures.
However, stainless steel is naturally softer than hardened carbon steel, which presents challenges when drilling into hard, i.e. high tensile, materials such as the steel substructure of a portal framed building. To overcome this, the drill point and lead-in threads of stainless steel self-drilling fasteners are carbon steel that is welded in place. A coating is then applied to act as a lubricant making installation consistent and efficient whilst preserving the integrity of the stainless steel body.
Long-Term Performance and Warranty Benefits
One of the key advantages of using stainless steel fasteners is their durability, with an in excess of 25-year Life Expectancy. Whether the project is large or small, problems with building integrity, be that water ingress, air leakage or worse, structural failure can cause major issues for the occupiers and owners. Stainless steel fasteners provide this reliability, allowing businesses to focus on operations without concerns about integrity.
Furthermore, stainless steel fasteners form a key part of system warranties, providing additional peace of mind to developers and investors. A warranted product ensures compliance with building regulations and long-term structural performance, reducing and managing risk..
Choosing the Right Grade: A2-304 Stainless
For the vast majority of metal roof and wall applications, A2-304 stainless steel (EN 1:4301 wire) is the most cost-effective and durable option when longer-term performance of 25 years plus is required. It performs well in almost all environments, including inland and coastal regions. Some suppliers may promote A4-316 stainless steel, often referred to as marine-grade stainless steel, due to its higher nickel, chromium, and molybdenum content.
Some suppliers provide the option of A4-316 stainless steel product alongside the A2-304 grade as both are designated as suitable for use in all environments as listed in BS EN 1993-1-3:2006 Durability of fasteners Classification of environment C1-C5. However it should be noted the A4 316 grade whilst also suitable, has a 20% increase in costs. While A4-316 provides increased corrosion resistance, it is only necessary for extreme environments.
It’s important to note that when selecting fasteners for swimming pool environments, neither 304 nor 316 grade stainless steel is suitable. The chlorine-rich atmosphere can cause what is known as ‘chlorine-induced stress corrosion,’ which presents a safety risk, particularly in safety-critical or structural applications. In such cases, higher-grade stainless steels with a minimum 7% Molybdenum—such as EN 1.4547 or EN 1.4529 wire should be used.
Conclusion
When planning your next construction project, stainless steel fasteners provide unmatched longevity, corrosion resistance, and overall structural reliability. Unlike carbon steel fasteners, which corrode and weaken over time, stainless steel fasteners maintain their integrity for decades, ensuring airtight, energy-efficient buildings with minimal maintenance. Choosing the right grade, A2-304 stainless steel (EN 1.4301) for “standard” construction you get the best value for your investment.
For more information on our high-performance, ETA-assessed, stainless steel fasteners, get in touch with one of our technical experts at Fixing Point, who can provide tailored solutions to meet your construction needs.
