To do or
not to do

Technical Assets: Aluminium/zinc and aluminium should never come into contact with copper, stainless steel, lead or brass, and must be protected by an inert membrane or be fully isolated by a rubber or neoprene gasket. Some building timbers can cause corrosion too, such a tanalised timber and cedar, due to the copper used in the treating process.

Why some metals should never touch

When different types of metals come into contact with each other, and particularly when water is present, chemical reactions take place. It’s important to know which metals should never touch, both to ensure the longevity of your roof, and that you are covered by the warranty, especially when adding things like solar panels and aerials at any point.

Design, pitch and aspect

ColorCote pre-painted metal roofing and cladding offer the biggest choice of colours and substrates, These can be rollformed or pressed into a range of profiles that give unmatched design flexibility, will look great, and be warranted to last.  ColorCote roofing has the strength to span wide spaces with simple and lightweight support systems and can be bent or curved to suit an almost unlimited range of innovative designs and roof pitches.

The house design will affect the life of your roofing and cladding. Avoid overhangs and designs that create unwashed areas. They won’t be naturally washed down by rainwater so caked dirt, salts and other corrosive elements will accumulate.

Good design can get rid of most unwashed areas at the planning stage. Roofs need to be washed down on a regular basis, so consider access. If the pitch of the roof is too steep to walk on safely, you might have to hire a cherry picker or crane for periodic maintenance.

The aspect of the roof is important, especially in severe environments. Salt-laden air driven in from the sea under the roof profile will accelerate corrosion. Spouting, valleys and low-pitched roofs also need to have the correct fall to prevent ponding which can accelerate potential corrosion.

Colour and reflectivity

Some local authorities and councils want to reduce the impact of construction on the visual landscape, particularly those in rural, coastal and alpine areas. They want new buildings to blend in with the natural environment and are enforcing reflectivity levels. These are based on measuring the average values for reflected solar radiation from building products – the lower the value the less reflected light/glare.

ColorCote has a range of low gloss colour options designed to blend into the landscape and meet council requirements around these reflectivity levels.

Minimum Maintenance Schedule

All pre-painted metal roofing and cladding products are exposed to the harsh effects of the environment, such as weather, airborne pollutants and salt spray. Regular maintenance of ColorCote pre-painted products will increase durability and is a requirement of your warranty.

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MagnaFlow Overview

MagnaFlow Technical Brochure

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Not all warranties are created equal. Most roofing companies offer a warranty of some kind, but just because a company is willing to give you a warranty won’t make your roof or cladding any more durable or resistant to the elements.

A 15-year warranty on a basic roof in a harsh or marine environment might seem attractive at first glance. But read the fine print – it probably requires monthly scrubbing with a hose and brush. Are you prepared to get up on the roof every month and do this? Because if you don’t, and the roof begins to fail, you might find that the full replacement cost is at your expense.

All ColorCote roofing and cladding products come with a written warranty backed by Fletcher Building, one of NZ’s largest companies. Our warranties are specific to a particular building, where it is sited, and the type of roofing and cladding product used. Because we make sure the right product is used for its environment, only normal maintenance (usually a wash every six months) is required.