General News

At Steel Studio, we have done extensive research in order to determine what thicknesses of glass is suitable for the different balustrade designs by performing numerous tests using different fittings, accessories and fixings. In our findings, only 10% of the tests using 8mm glass have been able to withstand the 400 Joule Human Impact Test (also known as the Swing Bag Test). We have found that there are many factors that influence the way the glass behaves in a test, namely:

• The spacing between fixings
• The edge distance of the fixings from the glass
• The diameter and proximity of the holes in relation to the edges
• The surface area of the fittings
• The type of material the fittings are manufactured from
• Quality of the glass
• The thickness of the glass

Based on our tests, we do not recommend using 8mm glass. Our tests were performed under strict supervision in a workshop environment to ensure a perfect installation, and as we know out in the field having the perfect environment is not always the case. In a “real world” setting, screws or bolts may not be torqued 100% correctly and there may be alignment issues and a host of other factors. These factors will also reduce the chance of the glass passing the test, and it is for these reasons that Steel Studio will only install a minimum of 10mm thick toughened glass in applications where the glass is attached to the uprights by means of patch fittings. This is not always the case though, as sometimes 12mm toughened glass is required because of the distances between the uprights. Steel Studio will always have a Professional Engineer approve the design prior to manufacture ensuring a safe product is installed on every project and in accordance with the South African National Standards (SANS).

Steel Studio is proud to say that currently 95% of our stainless steel is manufactured in South Africa, coming from The Columbus Stainless Mill in Middleburg which is 76% owned by Spanish giant Acerinox, and the balance of 24% of the shares held locally by the Industrial Development Corporation. Previously Steel Studio had brought in the majority of their stainless steel from the East, however, due to many reasons, we recently made the decision to buy locally and support our own country by promoting job creation. These were both important factors in the decision, however the quality of the materials came first and foremost. Quality standards from the East resulted in a number of issues and although we are now paying a premium by sourcing locally, we are confident that our clients will be receiving the best quality of stainless steel. By purchasing our steel locally, all material is now fully traceable and certificates are provided with every delivery. These certificates prove that the correct levels of Chromium, Nickel, Molybdenum etc, are contained in our material. We are also guaranteed that the stainless steel conforms to the required strength specifications. Strict quality control procedures are in place at the Spanish owned mill, which we believe are at the highest European standards.  It is very important to note that because Steel Studio utilises our stainless steel for the manufacture and installation of balustrades, the strength of the material is paramount. Balustrades are not only there to look pretty, but more importantly to provide a safety function.  While most of our competitors are sourcing from the East, and consider the look of the stainless steel to be the most important we at Steel Studio understand the importance of the strength of the stainless steel. The strength of the steel should be taken into consideration first and foremost: Can you imagine a balustrade collapses at a stadium where 20 people or more may be leaning on it? This is possible if the stainless steel is not manufactured to the correct strength standards as defined by ASTM (American Society for Testing and Materials). This is the standard according to which the stainless steel should be manufactured, and we at Steel Studio are confident that the stainless steel we are purchasing conforms to these standards.

We at Steel Studio are excited to announce our involvement in the new Sandton Skyedevelopment. The balustrade detail we are installing consists of a stainless steel rails system, a post and glass balustrade detail and various handrails throughout the project. The development will consist of three 15 storey buildings which will have 180 apartments per tower ranging from one and two bedroom apartments as well as 3 bed en suite Penthouses. The project is a lifestyle development that will be managed like a luxury hotel featuring a dedicated front desk and concierge, trendy restaurant, cocktail bar and delicatessen. Tenants will be able to enjoy the services of a personal in-room chef by arrangement, private butler service and 24 hour room service. There will also be additional facilities such as a private lounge and library, as well as a wellness spa and fitness centre that will be equipped with a heated pool. There will also be a Business Centre within the development featuring executive conference facilities, Internet facilities, health bar, hair salon and a kids zone. Sandton Skye will feature 5 Star Luxury Hotel living in the heart of Sandton on Stan Road, Morningside Ext 6. Construction is ongoing with Tower One opening mid 2014. For more information on the development please visit the Sandton Skye website.

The frameless, transparent balustrade design is becoming ever more popular in buildings worldwide and as we all know glass can be unpredictable, given that it is an extremely brittle product. The South African National Standards (SANS) does not state that a handrail is required on frameless glass, however SANS does clearly define the loads that balustrades must withstand in certain occupancy categories. The intended use of the building will determine the load the frameless glass balustrade must withstand. For example, the load the glass needs to withstand in a residential house is far less than would be expected for a balustrade system at a stadium. The defining factor is that the frameless glass balustrade is capable of withstanding the specified load, and not whether or not a handrail is fitted on top. The reason why handrails are fitted on top of the frameless glass balustrade is to assist with distributing the load when impacted, helping to reduce the thickness of glass required and bringing down the cost of the balustrade system. At Steel Studio, we have performed countless tests using different fittings and thicknesses of glass to determine the best solutions for projects. Every project or design will vary in terms of the specifications and factors, such as the size of glass panels needed, the thickness of the slab edge where the fittings need to be mounted, the wind conditions, as well as many other factors that need to be taken into consideration. It is almost impossible to state categorically what thickness of toughened glass can be used without fitting a handrail. It depends on the specific project and design. There are many ways where frameless glass balustrades can be installed without a handrail, however, clever engineering is required to ensure that the specifications are correct and compliant. The thickness of the glass, the size and material type of the fittings, hole diameters in the glass for example, are all extremely important factors that need to be taken into account in the specifications. If you are considering a frameless glass balustrade system without a handrail, please ensure that your balustrade supplier of choice provides you with a professional Engineers certificate stating that the design will comply with the South African National Standards (SANS). This type of design can be extremely dangerous if not designed by an engineer.

Engineers and Architects have always been inspired by glass as a building material. As methods of toughening become more cultivated, glass as a structural element has become more widely acceptable.  Transparent structures, such as glass balustrades offer unobstructed views at all times while minimising interference with the appearance of the building, all without compromising safety.

How It Is Made

Toughened glass is made from annealed glass through a thermal tempering process. The uneven heating method causes the cooling glass to form layers instead of a solid sheet. The glass is placed onto a ceramic roller table and is pushed through a furnace that heats the glass to approx. 720 °C. Once the glass is heated, the outside is rapidly cooled which “freezes” tension into the glass. By using this method, only the outside is solidified, leaving the interior fluid.

Why Choose Toughened Glass?

According to South African Glass Standards, Grade A toughened safety glass “may be used where the possibility of human impact exists or in any situation requiring strength, safety or resistance to temperature fluctuations.” It is also advisable to refer to SANS 10137 (The installation of glazing in buildings). In comparison to ordinary glass – which leaves behind sharp splinters from breakage -toughened glass fractures into small, relatively harmless particles in the event of being broken or failing, drastically lowering the chances of injury. Toughened glass has the highest resistance to impact and through the manufacturing process it can be up to 5 times stronger than regular glass, which makes it ideal for use in balustrades.

How Do I know If I Have Toughened Glass?

According to the National Building Regulations SANS 10400 Part N: Glazing – The panes of all safety glazing material shall be permanently marked by the installer in such a manner that the markings are visible in individual panes after installation. Toughened safety glass is permanently marked at the point of manufacture and must include the glass code. If you are at any point unsure about that glass that you are using, you should always ask if your glazier/contractor or glass supplier is a SAGGA accredited member.  

We are passionate about breathtaking designs and have succeeded in designing, manufacturing and installing what we feel are truly superior balustrade systems since inception.  Of all the materials that we use, we’re faced with the most questions and concerns regarding glass balustrades. Many of our clients are sceptical at first about the safety of this material. To help clarify any concerns, we’re going to run you through the facts so you can make an informed decision when considering installing glass balustrades in your residential building. Currently there are a variety of glass balustrade designs that can be installed in residential projects. Frameless glass systems fixed into a channel are arguably the most popular due to their “physics defying” appearance and also due to the system allowing uninterrupted views. Apart from frameless glass balustrades there are, stainless steel posts with glass infill panels, frameless glass options side fixed to a staircase or to a balcony with stainless steel standoff components and many different, attractive handrail fittings that can attach to the top of any of the glass balustrade options. Once our clients have been shown the variety of glass balustrade options, they often ask “are these systems safe in my home or residential building?” Lets start by clarifying what is considered to be safe. In order for a balustrade system to be considered fit for occupation and thus considered safe, it has to take the required load dictated by SANS relevant to balustrades, if this is the case the building owner will be supplied with an occupancy certificate once the project is completed. How do you know if you will receive an occupancy certificate at the end of your project? By employing a SANS compliant balustrade manufacturer that only designs, builds and installs SANS compliant balustrades. For more information read our recent article onglass standards and the South African Glass and Glazing Association’s article aboutSouth African glass standards. To ensure you’re getting a compliant and quality product it is best to do your homework and find out if the balustrade company is part of SAGGA (South African Glass and Glazing Association), the GMBA (Gauteng Master Builders Association). Any legitimate and accredited balustrade manufacturer will insist that your glass balustrade system is compliant and will explain to you your liabilities in terms of the SANS regulations.

So to answer the initial question, glass balustrade systems are safe in residential buildings if they are installed by a SANS compliant professional or company.

In an effort to protect our clients, we take away any liabilities if the balustrade designs are supplied with a design and supply contract by their architect. The balustrade sub-contractor will also issue an engineers sign off for your balustrade project, so that when your building inspector needs to issue your occupation certificate the engineers’ sign off is already on hand. Even if after you are aware of all the liabilities, you choose not to install a SANS compliant range of balustrades, you are indemnifying the balustrade contractor of all liabilities on the balustrades and you become liable for any incidents should there be any from the balustrades.  

Anyone who’s visited our news section recently would have noticed that we’ve been putting a lot of emphasis on the South African National Standards, also known as SANS, in specific relation to balustrade installations.  We’re deeply concerned about the lack of understanding of and compliance with these legally required codes and are doing our best to help educate building professionals and customers about their responsibilities regarding these regulations. We were recently asked an excellent question by a structural engineer and we thought it best to share the question and our response with all of you. In our recent article, your responsibilities as a construction professional regarding theSANS, we discussed the importance of getting a certificate stating that the balustrades meet or exceed the minimum requirements of the SANS, bearing in mind that there are defined loading requirements for certain occupancy categories. The structural engineer called us and asked under which circumstances he becomes responsible for the sign off of the balustrades. Our operations manager, Frans Fourie explained the following to him:

• Firstly it is not always the structural engineer on the project that must sign off the balustrade design.
• The client needs to make sure that the balustrades are signed off at the design stage. There are three scenarios that the client will encounter when having the balustrades signed off, namely:
  1. The architects drawing specifies that the balustrade contract is a design and supply contract. Steel Studio would therefore appoint an engineer to sign off on the design before continuing with manufacture and installation.
  2. The client chooses not to issue a design and supply contract. The client is therefore responsible to appoint the engineer to sign off the balustrade design before manufacture and installation and in turn indemnifies the balustrade manufacturer from any design liabilities.
  3. The client doesn’t know any better. It is then the balustrade manufacturer’s responsibility to point out to the client, firstly that they are liable if they choose not to install balustrades that comply with the SANS regulations. Secondly, they will not receive an engineer’s sign off from the balustrade manufacturer if they do not install a balustrade system that complies with the SANS. Lastly, they will be indemnifying the balustrade manufacturer from any liabilities if they do not install balustrades that comply with the SANS regulations. The client is now aware of the options and consequenses of their decision. If they insist on a design that doesn’t comply with the SANS, they must realise that no engineer will sign off on the balustrades and in the case of a new build, the building inspector will not issue an occupation certificate.

To clarify the structural engineer’s question, he is only responsible for the balustrade signoff if the architect has not issued a design and supply contract to the balustrade company and if it is in his scope to sign off the balustrades. That being said, we are now motivating architects to place the following notice on their drawings so that we can do the engineers sign off and as a matter of convenience and take the liabilities of the balustrades off the architects/clients’ hands. “The balustrades are a design and supply contract, and the subcontractor must provide a professional engineers certificate on completion. All shop drawings submitted for approval, need to be first signed off by the subcontractors professional engineer prior to submittal.”

Like the name suggests, stainless steel does not corrode or rust like carbon steel does. However, stainless steel is not 100{19cc6dfde2095820d75378ef5ea2a7429af84c4e3caa3f1811d59515c3bb9677} stain proof and in certain situations can be subject to staining, especially in coastal regions. What separates stainless steel from carbon steel is the amount of chromium that is present in the steel and that consequently forms a protective layer or passive film of chromium oxide. This film prevents corrosion by blocking oxygen diffusion to the steel surface and prevents corrosion from spreading into the metal’s internal structure. To prevent stainless steel from staining, a basic maintenance routine is recommended. We recommend cleaning stainless steel as often as you would your windows. Cleaning can be performed with clean water or a detergent. For stubborn marks we recommend contacting your supplier for expert advice. A basic maintenance schedule will help ensure that your stainless steel has a long, stain free lifespan. The most common type of stainless steel staining is known as tea staining. Tea staining is the brownish discolouration of the stainless steel surface. It does not affect the structural integrity of the steel and is entirely aesthetic. Tea staining occurs most commonly within about five kilometres of the ocean and becomes progressively worse the closer the stainless steel is to the shore. However wind exposure, pollution levels, local sheltering and high temperatures are known to create environments where tea staining has occurred up 20 kilometres from the ocean shore. In total there are 6 factors that play a part in tea staining, namely:

1. Presence of corrosive substances – The presence of sea salt on the surface of the stainless steel is one of the major factors that cause tea staining.
2. Atmospheric conditions – A combination of atmospheric conditions with high humidity and a high temperature creates optimum conditions for the occurrence of tea staining.
3. Surface orientation and design – Poor drainage promotes tea staining whether it is because the surface is near horizontal or has a texture that traps contaminants.
4. Surface roughness – Deep grooves or metal folds on a surface are more susceptible to staining because they can trap salts (chlorides). When the surface dries the salts become concentrated, making the conditions more aggressive.
5. Surface characteristics – To achieve the best corrosion performance of a stainless steel, the surface should be clean, free of contamination such as carbon steel or manganese sulphide inclusions, and have a continuous passive layer. Neglecting the surface of stainless steel increases the chances of tea staining.
6. Appropriate grade – There are several hundred grades of stainless steel with different chemical composition but only about 10 in common use. All owe their corrosion resistance to the thin chromium oxide film on the surface, although other additions such as molybdenum and nitrogen can improve the corrosion resistance, especially in corrosive environments.

Stainless Steel is inherently corrosion resistant materials that do not need additional surface protection to enhance their appearance and durability. Some routine maintenance and cleaning is needed to keep stainless steel surfaces in good condition so that the aesthetic appearance and corrosion resistance are not compromised. These guidelines are to give building owners, developers and facility managers advice on efficient, cost effective cleaning that will allow them to take advantage of the corrosion resistant properties of stainless steel.

The Self-Repair Mechanism of Stainless Steel

It is important to understand why stainless steel is so corrosion resistant. The alloying elements in stainless steel form a thin, transparent “passive layer” on the surface. Although this protective passive layer is only a few atoms thick, it instantaneously reforms in the presence of oxygen from air or water, so even if the material is scratched or damaged the passive layer continues protecting the surface from corrosion. This explains why stainless steel does not require any coating or other corrosion protection to remain bright and shiny even after decades of use.

Initial Cleaning

The first cleaning is generally done before the building is handed over to the owner. If the stainless steel parts have been protected adequately then simple “maintenance cleaning” at the hand-over stage will probably be sufficient. Specialist cleaning is needed to clean mortar and cement splashes as well iron particles which can dramatically reduce the product’s lifespan if not attended to properly.

Maintenance Cleaning

On external applications, such as facades, rainfall can normally be expected to wash off accumulations of dirt and other deposits efficiently, depending on the amount of exposure of the elevation. Special attention should be given to sheltered areas during routine cleaning to ensure that accumulations of airborne contaminants are removed. On interior applications, finger marks can be an issue. There is a wide range of finishes available for stainless steels, many of which are particularly suitable for use in heavily exposed (high traffic) public areas. Selecting finishes that are less sensitive to fingerprint marking in the design process will reduce the effort and costs of cleaning during the service life of the finished building.

Cleansers

To remove fingerprints and other marks from architectural finishes, soapy water or a mild detergent are usually safe and successful. Proprietary spray cleaners are available, which combine ease of cleaning with a light film that produces an even and smooth lustre. Mirror-polished stainless steel can be cleaned with glass cleaners. These products should be selected chloride-free. For more stubborn stains, mild household cream cleaners should be effective. This should also be suitable for cleaning off watermarks and light discolouration. After cleaning, remove the residues with (preferably de-ionised) water (available in supermarkets, e.g. for steam ironing or car batteries) and dry to avoid streaking and water marks. Severe oil and grease marks can be removed with alcohol based products, including mentholated spirit and isopropyl alcohol or other solvents such as acetone. Care is needed with solvents to avoid spreading the staining on the stainless steels, which can then be difficult to fully remove. It is advisable to apply clean solvent several times with a clean, non scratching cloth, until all traces of the partially dissolved oil / grease are removed. Paint and graffiti can be treated with proprietary alkaline or solvent-based paint strippers. The use of hard scrapers or knives should be avoided as the underlying stainless steel surface may become scratched. Heavily neglected surfaces can be treated with metal polishes, such as those for cleaning chromium-plated items (e.g. automotive trim). Furthermore, polishes used for re-finishing car paint can be considered. Care must be taken as highly polished surfaces may become scratched with these cleaners. Alternatively, use a proprietary stainless steel cleaner containing phosphoric acid to remove contamination, rinse with de-ionised water and dry. It is advisable that the entire surface of the component is treated so that a patchy appearance is avoided. Cleaners that should NOT be used on stainless steel include:

• chloride-containing cleansers, especially those containing hydrochloric acid
• hypochlorite bleaches should not be used on stainless steel; if applied accidentally or spilt on stainless steel surfaces, should be rinsed off immediately with liberal amounts of fresh water
• silver-cleaners must not be used on stainless steel

Cleaning Utensils

A damp cloth or chamois leather will usually be suitable for removing normal soiling, fingerprints, etc. For more stubborn dirt, nylon pads such those known as “Scotch-Brite” pads are usually satisfactory. Non-stainless steel based scouring pads, cleaning wool or wire brushes must not be used on stainless steel. Apart from scratching the surface, these pads can leave carbon steel deposits on the stainless surface, which can subsequently develop into rust spots, if the surface becomes wet. Soft nylon brushes can be used for cleaning stainless steel with patterned finishes. Non-stainless steel wire brushes must not be used. On “grained” directional finishes, such as EN 10088-3 types G, J and K the direction of cleaning strokes should be along the grain and not across it. Where water has been used for cleaning or rinsing, wiping the surface dry to prevent watermarks, especially in hard water areas may be advisable. The use of de-ionised water will prevent the formation of hard water staining.

Cleaning Intervals

The cleaning of stainless steel items for building interiors is really no different to other materials. Cleaning should be done before there is a visible build up of soiling or finger-marking, so that the effort and cost of cleaning is minimised along with the risk of marking or altering the appearance of the surfaces. On building exterior applications, stainless steel may be exposed to a wider range of potentially more aggressive environments as a result of contact with:

• marine atmospheres
• environments laden with industrial pollutants
• salt spray from road de-icing salt
• atmospheric dirt and traffic film

It is a good practice to clean the stainless steel at the same frequency as the building’s windows (glazing). Depending on the severity of soiling and deposit build up, routine cleaning frequencies of 6-12 months for light soiling and 1-3 months for heavy soiling or environments such as those listed above is advisable. A stainless steel cleaner containing phosphoric acid will remove this form of contamination.  

It is with great excitement that we announce that Steel Studio will be taking part in the 2014 Decorex Cape Town exhibition. Our stand number is K33 at the Cape Town International Convention Centre and we’d like to officially invite everyone who reads this and that is in the vicinity to come past and see what we have on show. The prestigious exhibition will take place between the 25th and 28th April. Decorex SA, South Africa’s pre-eminent décor, design and lifestyle exhibition, is one of the South African décor and design industry’s leading and most trusted brands. Founded in 1994, the award-winning Decorex SA portfolio continues to play a pivotal role in shaping the industry. We’ll be showcasing some of our work and giving attendees the opportunity to ask our trained staff any of your balustrade, staircase and pool enclosure related questions. Decorex Cape Town has taken home a number of awards – and it’s no secret why. Every year, it brings together an unrivalled collection of South African design icons, leading brands and rising stars. These exhibitors reflect the mother city’s other name, the city of chic. Cape Town thrills to their bold approach and sophisticated style. We’re proud to be part this prestigious event and look forward to showcasing what Steel Studio has to offer. See you there!