Frequently Asked Questions
Galvanized Steel uses a Zinc coating to protect the steel, while Zincalume® uses both Zinc and Aluminum. Zincalume® has proved to be a much more durable product, with steel lasting 6 to 9 times longer when compared to standard galvanized products.
Some tile manufacturers use a stone coating, but then paint over the top. The chip coverage is often poor and the paint tends to change colour over a shorter period of time.
By using natural stones, AHI tiles will not change colour. Also the chip coverage and the bonding of the chip is generally to a much higher standard when compared to other metal tiles. This is important particularly over time because it ensures the basecoats and substrates are protected from weather damage and thus ensuring that the product looks better for much much longer.
Over the years AHI has established that the steel used must achieve the optimum balance of strength and flexibility. We steel specification which is stringent for all AHI factories has to take these into account and we have settled on a gauge and specification that strikes the optimum balance between these factors and the final product price.
AHI produce over 25 million tiles a year through our own factories and licensees. As the world largest producer or metal roofing tiles and as the original manufacturer of such products, we like to think that we have some degree of expertise in this field.
AHI have been making painted tiles for 35 years and have developed in house paint technologies to improve colour durability, particularly in severe UV environments. All new colours are only supplied to the market after extensive advanced weather testing is carried out, to endure that the colour durability will meet the AHI standard and be covered by the warranty for 15 years against colour change.
The chemicals and pigments used in this technology may be significantly more expensive than in paint supplied on long run metal roofs, which invariably prohibits their use for most long run roofs, since this is usually a price sensitive market.
There are certain efficiencies to be achieved, particularly when maximizing loads in shipping containers. Also steel is generally supplied on coiled rolls and this is usually most cost effective in the size purchased to make or tiles at the width that they are.
Longer tiles lose strength in the installation and also look less appealing. AHI with over 50 years experience in producing these products have settled on product sizes most suitable and desirable across their range of world markets.
Our market is roof tiles. There are plenty of manufacturers making long run roofing and we do not believe that our customers want their beautiful AHI roofs to be comparable with what is essentially an industrial use product.
These also tend to be used at the economy end of the roofing market, while our products are generally supplied at the premium end of the roofing market.
New Zealand is the cheapest place for AHI to make our roofing products. Fletcher Building, our parent company is the largest purchaser of steel in the New Zealand market, so our purchase of the base material is very competitive. Since the cost of steel represents the largest element making up the cost of the tile, this is critically important. Also we are close to the source of other raw materials and also close to the port in Auckland so containerized exports become easy.
Since cost of labour and cost of freight together usually add only 10-15% of the landed cost in African markets, it makes this the most efficient source for us to supply from and also means that our price in African markets is kept as low as possible.
Our pricing is structured so that there is no advantage in individuals purchasing small quantities and importing themselves. Our distributor’s prices are structured so that internationally, prices remain relatively equal, with variances only according to shipping costs and local import duties and taxes.
Furthermore, our distributors are trained in product installation to insure you receive the best service. They are also authorized to issue a 50 year product warranty, issued by the manufacturer and transferable should you sell the property. No warranty is valid unless supplied by the distributor in the country of installation.
Although it is easier to install our roofs than many other types of roofing, there are certain key steps that need to be adhered to, which is why we recommend clients using only recommended installers who have been trained by the distributor. Otherwise, installation manuals or installation training videos are available from the distributor and should be given to each client as part of their purchase.
It is normal that in a dusty environment ALL roofs will collect dust and dull the colour. Our roofs are no different to other roofs in this respect and will be easily restored after rains.
You tend to find that the timber used under our installations absorbs a lot of the residual rain noise. When the tile is installed, it is firm and there is very little reverberation like that experienced with long run metal roofs.
The stone chip also reduces rain noise further, so when compared with concrete or clay roofs, the rain noise is only measurably higher by a 10-12%, whereas a long run sheet will create some 30-40% higher noise levels.
The difference of AHI roofs compared to a concrete or clay tile roof may therefore be considered negligible.
Drinking water collection from AHI roofs is approved and certified by the WHO.
AHI Roofing Tiles contain a biocide in the basecoat which is harmless does not effect the WHO approval for drinking water collection, but will prevent the build up off moss or algae for the first 5-8 years following installation. After this period, any organic growth will depend on the location and environment and will be the same for AHI roofs, or roofs from other manufacturers.
On AHI roofs, this organic growth can be killed with a sodium hypochlorite, dilute to a working concentration of available chlorine of 3% and apply liberally to the roof. After rainfall the growth should clear.
The tiles are made from natural rock so mostly we are limited to those colours. When we want to use a colour that does not occur naturally, (e.g. blue chip), then the chips are individually ceramicly coated with the required colour. These are kiln fired to endure that the colour will last and therefore carry the same warranty against colour change as the natural rock colours.
If the client wants a colour not currently in our range, to do this efficiently, we need a large production run, so orders are limited to those exceeding 30,000 tiles. If the client just wishes to have a different blend of chip colours from the existing range, then this can be accommodated with a minimum run of 5000 tiles. Any extra product produced will have to be also taken by the customer. Sometimes this can run as high as 10% over order.
As explained in the previous answer, the blue is made using a ceramic coating on the stone chip. The cobalt used in this colour process is expensive, so this adds a little to the final cost.
The shingle tile is pressed in a 4 directional corrugation. It is a slow process to get this right. The tile is also covered in 2 colours of stone chip. The additional cost of the shingle therefore relates to a greater manufacturing cost when compared to the normal Heritage, Classic, or Shake profiles.