The roof not only shields people from the elements, the surface coating can provide an energy efficient barrier, which needs maintaining.
Over time, the wind, rain, airborne pollutants and harsh UV rays of the sun degrade the roof’s surface coating, reducing its protective qualities, colour and sheen.
Because the roof is affected by the extremes of weather, the rules of painting – thorough preparation, the right top quality paint and correct application – are important.
To restore the roof and its good looks, the experts at the Rohm and Haas Paint Quality Institute (PQI) recommend recoating it with an environmentally friendly, 100% acrylic water-based coating.
Many people believe that a weathered roof that is constructed from factory pre-painted galvanised or zincalume steel sheeting, such as Colorbond or Colorsteel, cannot be recoated. That is an urban myth, says Mike Beresford, Manager, PQI in Australia and New Zealand.
Pre-painted steel sheeting should be cleaned with a mop or soft bristle broom, washed with water and detergent to remove any chalkiness, then rinsed with clean water before being recoated with a top quality, 100% acrylic roof paint.
More severe damage or corrosion needs to be fixed first before cleaning. Overpainting Colorbond and Colorsteel roofs may void the manufacturer’s warranty. This should be checked before the start of painting.
Leading paint manufacturers now offer specialist acrylic roof paints in a range of specific colours that are formulated to resist the extremes of weather.
Getting the right colour is no problem. Most quality paint manufacturers offer acrylic water-based roof paints in a range of colours that match the original Colorbond and Colorsteel colour and semi gloss sheen level.
Some speciality roof paints include infrared reflective pigments that are able to reduce the amount of heat transmitted through a roof. This can help to lower temperatures inside the home and cut back on the carbon emissions generated by air conditioners.
If the roof is being used to collect water, check the can to make sure the paint to be used is suitable for the collection of drinking water.
Roofs can be steep and dangerous, so it might pay to get a quote from a professional roof painter.