Landscape Insight December 2017 - Page 20

5 TOP TIPS CHOOSE A STEEL AND FINISH THAT LASTS FIVE TOP TIPS CHOOSE A STEEL AND FINISH THAT LASTS BY URBAN STREET DESIGNS Choosing materials is an important consideration in all well designed products, for structural stability, finish and longevity. When it comes to steel and its properties we at Urban Street Designs have a vast knowledge and often get queries about corrosion and the life expectancy of our steel architectural products, below are five of our top tips to help you when specifying steel for a product or project. 1. STAINLESS STEEL GRADES – PICKING THE RIGHT GRADE When specifying a material grade in architectural stainless steel products it is easy to be over cautious. The two most common grades speciied in the designs we receive are 304 and 316, the only real diference between the two being 2-3% of molybdenum which gives 316 an increased corrosion resistance to chlorides like sea water and de-icing salts. If there is one piece of advice we give to our customers it is that unless your product is going in a coastal area or in areas with high chloride exposure then 304 is aesthetically identical and more than suitable, leaving you with more resources to allocate elsewhere in your projects. 2. HOT DIP GALVANISING – AVERAGE CORROSION RATES We all know the beneits of Hot Dip Galvanising with its long life expectancy and zero maintenance, but how long does it actually last? This is a question we get asked quite a lot. Hot Dip Galvanising has an average coating of 85 microns and depending on its environment depends on it corrosion resistance, for example the majority of Central London has an average corrosion rate of 1 micron per year, meaning its average life span is 85 years. The website www.galvanizing.org.uk has a corrosion map which will tell you the exact corrosion rate of your projects location; this is a great tool for everyone in the industry to have. 3. CORTEN – THE NATURALLY WEATHERING STEEL What is not to love about Corten, it’s a high strength, low alloy, weldable structural steel, possessing excellent weathering resistance. Its corrosion resistance builds up when it oxidises and forms a coherent patina that adheres to the surface, creating a reddish brown hue. When speciied in a project it is often because the designer likes the aesthetics of the Corten patina, which in normal weather conditions can take 18 to 36 months to stabilise. Urban Street Designs use a special in-house process to help speed the patina up, we also encourage good ventilation to be designed into the product as the patina relies on the surface being routinely dried. which is a pre-coated mild steel. We can also put a zinc rich primer on any product and with a layer of powder-coat on top you can give your product up to a 25 year life span. This is a great cost efective alternative to galvanising. 5. JUST ASK! No one can be an expert in everything, talking to people in the industry is the fastest way to increase your knowledge. We pride ourselves on being experts in our industry, so when specifying material to a product or project, Urban Street Designs have a full team of designers and engineers to give advice and discuss any queries you have. 4. ZINC RICH PRIMING AND POWDER-COATING If your product is made from 3mm thick material or less we can use zintec steel ABOUT THE AUTHOR: Urban Street Designs have over 35 years of engineering skill and expertise and have been providing a first class service within the industry since 1985. Our customers include architects, construction companies and local government to name but a few. All of our products are manufactured on site in the UK. www.urbanstreetdesigns.co.uk 20 Landscape Insight | December 2017