The highlight of the structural steel industry calendar, the 36th Annual Steel Awards hosted by SAISC (South African Institute of Steel Construction) was held on 13 September 2017. Garnering 56 entries from over 300 tems for projects demonstrating excellence in steel construction, this year's awards delivered on every front. Safintra South Africa sponsored the Factory and Warehouse category, while the overall winner for 2017 was announced to be the BMW H-EMS Roof Lift, submitted by Teichmann Structures – the main contractors for the project. In addition to being named overall winner, this project also won the Safal Steel Innovation Category.
South Africa embraces a variety of architectural styles, from Cape Dutch and French Huguenot to Tuscan and English. Some work, some do not, some are timeless, some are trite. But one fact is a game changer – the need to look at sustainability in the built environment. And steel roofing is leading the charge for change.
Roofing needs to rise to the challenges posed by global warming, the move to eco-neutrality, the rising cost of energy and the financial returns required by an investor.
Metal roofing has impeccable sustainability credentials, and its versatility makes it the material of choice for stunning architecture from modern to traditional. But it is functional performance that sets it apart.
A building is always an investment. So durability and the lifetime costs of occupation and ownership are critical. So too is its impact on the well-being of the people who live and work in it, and the way it uses resources. Quality components which are correctly installed in a well-designed roofing system offer returns that are financial, social and environmental.
The Safintra Innovations Roadshow will unpack a basket of best-of-breed components, which make up a metal roof system that delivers returns for the full occupied life of the building – each component separately warranted but when used together, the system stands apart.
- For increasingly violent weather, Safintra has a new generation Saflok clip system for concealed fix roofing.
- For energy-efficiency, Safintra has clamps that will make the roof a source of power without compromising the performance or warranty of the roof sheeting.
- To minimise maintenance costs, Safintra offers fasteners which will have a life expectancy longer than that of the roof sheeting.
- To reduce energy costs and lower the environmental impact, Safintra offers an over-roofing and roof spacer system which ensures the insulation you buy gives you the performance you paid for.
- And to reduce its environmental impact, Safintra has the long-span Metsec steel purlin system.
Finally, Safintra will warrant the integrated roof system for performance – thermal, functional and durability. That is a game changer.
Safintra South Africa
Tel: (011) 323 6300
Website: www.safintra.co.za / www.safintra.com
One important item is the weight of the roofing system. Today’s available roofing materials include a wide range of weights. For comparison, let’s look at the weight of one “square” of various products. A “square” covers 100 square feet of roof area.
- ALUMINUM: 40 – 70 pounds
- STEEL: 80 – 125 pounds
- COPPER: 100 – 125 pounds
- COMPOSITE / POLYMER PANELS: 150 – 275 pounds
- FIBERGLASS / ASPHALT SHINGLES: 275 – 425 pounds
- CONCRETE TILE: 400 – 700 pounds
- SLATE: 900 – 1300 pounds
- CLAY TILE: 1100 – 2000 pounds
Why Does Roof Weight Matter?
The weight of a roofing material, when carefully considered, can be a significant portion of your roofing decision.
Weight impacts key areas of overall roof performance
AGING STRUCTURES. As a structure ages, it weakens. Structural lumber may crack and foundations may move. A low weight roof system can prolong the structure’s life and integrity. A case in point is the First United Methodist Church in Sidney, Ohio. This impressive, looming structure had a clay tile roof that was about 80 years old when, at great expense, the decision was made to remove the tiles, clean them, put new underlayment on the roof, and re-install the tiles. Just a couple of years after this work was done, a major beam snapped above the sanctuary. It was unable to handle the weight of the roof.
SEISMIC ACTIVITY. In areas prone to seismic activity, heavy roofing can cause structures to slide off their foundations or even collapse. Lower weight products can be a good choice as much earthquake damage is sustained by structures with heavy roofs.
HIGH WINDS. Regardless of its weight, properly secured roofing materials can meet even the most strict wind uplift requirements. In the case of catastrophic storms, very heavy weight roofing materials pose a huge risk if they become airborne.
FIRE RISK. Many types of roofing materials are designed to resist combustion from exterior fires. However, most home fires start inside the structure. Firefighters are heavily trained in the risks of entering homes with heavy roof systems once the fire reaches the attic. Heavier roofs create a greater risk of collapse that could trap firefighters inside the structure. This means that firefighters have to contain the fire from the outside rather than enter the building and try to stop the fire.
RAW MATERIAL USE. Roofing materials come, in one way or another, from natural resources. The heavier the roofing material is, the more pounds of our natural resources are being consumed in order to create it.
TRANSPORTATION COST. Heavier weight roofing materials require additional fuel for transportation. With a low weight roofing material, as many as 300 squares or even more may fit on a semi-truck but weight limitations can hold that to 20 – 30 squares for very heavy roofing materials.
ENERGY EFFICIENCY. Heavy roofing materials typically have great thermal mass. While this thermal mass can offer some nominal R Value, it also holds heat. This means that summer heat absorbed by the sun can be held by the roof and continue to keep your attic hot even after the sun goes down.
The use of aluminium-zinc coated steel as a practical cladding material is gaining popularity along the coast of Africa.
Bounded by three oceans and the Mediterranean Sea, Africa has a vast coastline of 26 000km. Its deep rivers and natural ports have been historically important trading hubs and remain as vibrant nodes of urban settlement and business.
The populations of this vast coastline are blessed with abundant natural materials for building, but increasingly, as new infrastructure development booms, the use of metal as a practical, durable cladding material is taking off.
The Safal Group is the sole licensee of aluminium zinc coating technology in Africa and sells its coated steel sheeting along 12 000km of this coastline, down the eastern seaboard from Djibouti to South Africa in the extreme south, and up westward to Luanda in Angola.
All coated steels are not the same
Steel plays a huge role in development, but it does have an inherent weakness – when used unprotected and exposed to the environment, it rusts and corrodes. To extend the service life of steel, it is generally protected with a corrosion-inhibiting coating.
The two most commonly used coatings to protect steel are:
- Aluminium zinc coating (AZ) – aluminium and zinc.
- Galvanised coating (GI) – zinc.
The addition of aluminium to zinc in the coating alloy extends the service life of a steel roof by up to four times that of galvanised steel.
Comparison between AZ and GI coatings.
Source: BIEC International Inc., licensors for aluminium-zinc coating technology used by Safal Steel and other Safal Group coating mills in Africa
Made for Africa’s coastline
Aluminium zinc coating technology, developed in the 1960s in North America, enabled coated steel to deliver a service life of decades, even in aggressive coastal conditions. This development revolutionised the metal cladding industry, and is today the most widely used coating technology worldwide.
In Africa this coated steel is branded Zincal and its factory colour-coated derivative is called Colorplus, produced in Africa at three coating mills owned by the Safal Group.
The thicker the coating, the longer is the resistance to corrosion and the longer the life of the protected steel substrate, and a coating of 54 microns on Zincal Ultima gives it corrosion-proof performance credentials which are suitable for coastal areas where only aluminium sheeting was previously specified.
Taking a challenge head-on
In Safintra’s book of achievements, there is nothing better than a challenging project. This includes challenging locations, weather and most of all, the challenge of trying out a new product.
One such a challenge was the recent application of Safintra products at a newly-installed solar array on the Wild Coast.
Saflok 700 roof sheeting was rolled in aluminium 0,8mm material, transported to the location, installed and then over-fitted with Safintra S-5 roof clamps, onto which the solar panels were secured. Forming part of the approved range of Safintra Roofing System components, Safintra’s S-5 clamps do not void the warranties on the roofing material. This proved to be a critical factor in the financial feasibility of the project. To consider replacing part of the roofing system in this location, even 15 years down the road, was not an option. Safintra’s S-5 clamps are warranted for 25 years and have pull-out loads which are unbeaten worldwide.
The Saflok roofing profile has proven its performance as a sealed roofing system many times and aluminium was the ideal material to use in a location within 2km of the Wild Coast’s shoreline.
Another significant challenge was the timing on the project. Within two weeks, the roof sheeting was produced in the Durban plant of Safintra and loaded on a flatbed truck with clips, fasteners and other hardware. The clamps were put through final loading tests in Denver, Colorado.
A Safintra technical expert, as well as an S-5 technical expert from the USA, was present to ensure the correct installation of the sheeting and the clips above it, and the perfect alignment on solar panels on top of the lot.
Day 3: Tuesday
The S-5 clamps were put through final loading tests in Denver, Colorado, and test videos were sent to the client on the Wild Coast by satellite cellphone.
Day 2: Wednesday
Dustin Haddock left Denver, with the still-warm clamps in his luggage, for 20 hours of travelling.
Day 1: Thursday
Dustin was met by Marnitz Benecke of Safintra in Johannesburg for a late flight to Durban.
An early start from Virginia airstrip in a small plane, on site by 10am, finished by 3pm and back on the plane to Durban that evening.
The project was an immense success, and despite the long travelling hours, Safintra congratulated the team – in the Unites States and South Africa – on a job well done.
Bounded by 3 oceans and the Mediterranean Sea, Africa has a vast coastline of 26,000 km. Its deep rivers and natural ports have been historically important trading hubs, and remain as vibrant nodes of urban settlement and business. The populations of this vast coastline are blessed with abundant natural materials for building, but increasingly, as new infrastructure development booms, the use of metal as a practical, durable cladding material is taking off.
The Safal Group is the sole licensor of aluminium zinc coating technology in Africa, and sells its coated steel sheeting along 12,000 kms of this coastline, down the eastern seaboard from Djibouti to South Africa in the extreme South, and up west to Luanda in Angola.
All coated steels are not the same:
Steel plays a huge role in development, but does have an inherent weakness - when used unprotected and exposed to the environment, it rusts and corrodes. To extend the service life of steel, it is generally protected with a corrosion inhibiting coating. The 2 most commonly used coatings to protect steel are:
- Aluminium Zinc Coating (AZ) – aluminium and zinc
- Galvanised Coating (GI) – zinc
The combination of Aluminium and Zinc extends the service life span of a steel roof by up to 4 times that of galvanised steel.
ZINCAL ULTIMA – made for Africa’s coastline
Aluminium Zinc coating technology, developed in the 1960’s in North America, enabled coated steel to deliver a service life of decades, even in aggressive coastal conditions. This development revolutionised the metal cladding industry, and is today the most widely used coating technology worldwide. In Africa, this coated steel is branded Zincal, and its factory colour-coated derivative is called Colorplus, produced in Africa at 3 coating mills which are owned by the Safal Group.
The thicker the coating, the longer is the resistance to corrosion and the longer the life of the protected steel substrate, and a coating of 54 microns on Zincal Ultima gives it corrosion-proof performance credentials which are suitable for coastal areas where only pure aluminium was previously specified.
Who says it isn’t possible to have the best of both worlds? The look and feel of a traditional tile roof with the GREEN credentials, thermal efficiency, cost saving and lightweight properties of steel – It is possible with Safintra Roofing’s unique profile – Versatile.
Safintra Roofing celebrates its twenty first anniversary this year and has marked the event with a series of new product launches – amongst them the launch of the Versatile 5 profile, a wider version of the company’s Versatile 4 profile.
Use of this profile has exploded onto the South African market and particularly in the province of KwaZulu-Natal, where it has been used on a number of Department of Public Works developments. Tafadzwa Togarasei of leading Durban Architecture firm, DGIT Architecture explains: “I think the popularity of the Versatile profile can be attributed to a number of factors. Firstly, its aesthetic appeal. The beauty of this profile is that it indeed gives you the look of conventional roof tiles. More and more emphasis is being placed on the environment and sustainable building. Steel roofing is by far the most environmentally friendly option available. It is also a fact that in construction time is money. If you have a high quality product that meet standards and saves you time, on procurement, installation and maintenance, then that product is bound to be a winner. This product also enables us to lower the roof structure costs. Its availability in sheet form allows us to make use of fewer trusses, sometimes getting away with half the trusses that would have been required when using conventional roofing tiles. Transport costs are also reduced because a large quantity of sheeting can be delivered in one single delivery. Improved metal coating technology, such as Aluminium-Zinc coatings ensures that our clients have a quality maintenance free product with a superior lifespan.”
DGIT Architecture has specified the Versatile profile on a number of KZN Developments, specifically for the Department of Public Works. These developments include the Department of Education’s Empangeni Rail (Richem) Secondary School and Birdswood Secondary School in Richards Bay. The company has also specified the profile on a number of projects for the Department of Health.
Safintra Roofing’s National Marketing Manager, Sally Stromnes: ”We are extremely proud to add the Versatile 5 profile to our already extended range. We have had excellent reviews from our customers and feel that as more emphasis is being put on designing buildings that conform to environmentally high performing buildings and building materials, the use of steel will escalate. Apart from its obvious economical and environmental benefits steel roofing is also perfectly suited to the harvesting of rainwater, which we believe will become an area of key focus. Going forward, we as a company are committed to providing environmentally friendly solutions to the building industry with innovative products, such as Versatile 5”.
Today's trend for sustainable designs that reduce environmental impact is helping drive the metal roofing market to new heights. Understanding the engineering concerns fundamental to the proper design of metal roofing will enable specifiers to serve the long-term interests of their clients, and reduce liability for all concerned.
In large-span metal roofing applications, concealed fix roof systems are the logical choice – they are fixed to the purlin with a clip system, and are not pierced with any fasteners. The clips serve two purposes – they circumvent the need for holes in the sheet (which prevents the possibility of leakage through the perforation) and they allow the roof to expand and contract in a sliding movement over the clips.
Because the sheets can slide over the clips, they can be rolled in long lengths which can thermally expand without restriction. If the sheets were positively fastened through the sheet into the purlin, the fasteners would take the brunt of the force of expansion, and would tear larger holes in the sheet, or shear off. Consider that coated steel expands at a nominal 1mm per 1m, and it is apparent that a sheet of a mere 15 m will move by 15mm in heat. It is common best practice to not install a pierced fix sheet in lengths of more than 15m for this reason. Over 15m, a pierced fix sheet should be end lapped to allow for thermal cycling.
A concealed fix system allows sheets to be rolled in continuous lengths up to 120m or more. The lack of end laps further helps reduce the risk of leaks.
In these applications, with the size of investment concerned, engineering performance of the roof “system” is critical.
The first distinguishing characteristic of a concealed fix roof is the profile, which is both aesthetic and functional. For low sloped roofs, one is looking for a defined rib, with a wide deep pan to deliver excellent water run off at slopes as low as 2 or 3 degrees. The height of the rib is important as it also provides structural strength, acting rather like a mini I-beam.
Of equal concern is the design of the clip, as this is the “anchor” securing the sheet to the sub structure and holding it down in high winds. The material and thickness of the clip helps determine its inherent strength, which in turn helps to determine the minimum wind-uplift resistance requirements for a particular roof.
The overall “system” design defines the manner in which the clip locks into the sheet profile. The clip should engage every rib of the profile to prevent wind cushioning under the unsecured rib, and distorting the sheet off the clip. Generally, the more ribs that are secured with a positive clasp holding it to the purlin, the stronger the wind uplift resistance. If not positively secured, the ribs should be shaped to provide a strong and stable interlock with the clip at every point.
The system must be able to withstand the foot traffic and loads imposed by the installation of HVAC units, rooftop photovoltaic (PV) systems, or other utilities.
As a profession, you should demand full technical details of the system you intend to specify – and request technical support throughout the installation itself.
Safintra is proud to offer this service free of charge to its customers, from 7 branches countrywide.
With a contemporary design, Safintra’s Trimflute® metal roofing profile is both visually appealing and cost-effective.
A visually stunning and cost-effective metal roofing profile, Trimflute® is unique to Safintra South Africa and is now available in the Gauteng market. It has a subtle square fluted profile with a contemporary visual appeal, ideal for both roofing and cladding applications.
The Trimflute® roofing profile is especially cost-effective when used as side cladding on large industrial projects which have Saflok concealed fix or similar profiles on the roofing.
With a wider pan than any other square-ribbed equivalent, it delivers more than almost 10% cost advantages over both IBR roof sheeting and wider pan profiles such as Widedek.
Its wide pan has excellent water handling performance and the extra wide sheet, which provides over 1m effective cover after lapping, makes it highly cost-effective for budget-sensitive projects.
An ideal roofing solution for industrial, commercial and institutional buildings, this profile can be rolled in any coated steel or in aluminium.
The striking Govan Mbeki Sports Centre in Port Elizabeth, designed by Adendorff Architects & Interiors, features Safintra’s Trimflute® profile extensively for both roofing and side cladding. Apart from adding to the aesthetics of the development, the product was selected due to it being an economic choice.
Sally Stromnes, marketing manager for the Safintra Group, says: “South African architecture is right up there with the best the world has to offer, not only in its design, but also for its innovative use of steel for its functional benefits.
“Our built environment professionals and end-users have caught up with the environmental upside of using steel – its excellent thermal properties, its strength to weight benefits, and the fact that it is cost-effective, durable and completely recyclable. Add the good looks of a really elegant profile that is visually distinctive and metal sheeting demonstrates real value in both design and function.”
Safintra South Africa
Tel: 011 323 6300
The Safintra Group recently opened two new offices in Bloemfontein and Windhoek
Metal roofing manufacturer, Safintra, recently opened two new sales offices in Southern Africa. The new offices, situated in Bloemfontein and Windhoek, intend to help the company offer localised support to its customers wherever they might be.
Besides providing sales and technical support to customers in the Free State, the Bloemfontein office will also cover the Northern Cape. The Bloemfontein office boasts a showroom area that will be used by architects, engineers and contractors as a reference centre for product specification information and specialist installation advice.
The Safintra Group also has operations in ten other countries in the(delete) SADC, Southern and Eastern Africa including Mozambique, Zambia, Malawi, Angola, Tanzania, Kenya, Uganda, Ethiopia, Rwanda and Burundi.
Safintra Roofing & Steel
Tel: 011 823 4027
Fax: 011 823 4288