“The phrase carbon footprint is often used, but what is the real meaning of the term and how can we strive towards greener construction? Carbon footprint is a measure of the amount of carbon dioxide or CO² emitted through the combustion of fossil fuels; in the case of a roofing product, it relates to the total sum involved in making the product from the production of the raw materials, through to delivery to the factory, manufacture of the product, packaging, distribution and finally installation of the finished item.
“Once constructed, the roof may also contribute to the carbon footprint of the building it covers, by way of its performance in use and its ability to harness renewable sources of energy i.e. solar, wind or water. Consideration must also be given to what will happen to the roofing material at the end of its life and its suitability for re-cycling.
“Some roofing materials are greener than others by virtue of the fact that their production and use has the least impact on the environment in terms of both the CO² used to produce them and the resulting effect that they have on the natural environment. If you consider natural slate as an example - here the material is extracted from the earth, but as much as 95% of it is unusable and so goes to waste. Very often the resulting product must be transported many miles from the source to the end location as slate is these days more abundant in locations such as Brazil and China.
“Roofing materials can be costly and energy intensive to produce, in terms of both the labour and the machinery required and their subsequent distribution. Hence the ideal products are those which are made from re-cycled materials, which can be made with low energy production methods and can be packaged and distributed economically. Add to this, ease of installation, a long lifecycle and recyclable potential at the end of their life and they will score higher than those that do not.
“Owners of all buildings with a roof having a low carbon footprint can be assured of a sustainable and efficient roofing system which will provide effective protection to the building fabric for its determined life span. At the same time, it will contribute to reducing the environmental impact of the building.
“At Marley Eternit we have developed the EcoLogic roof tile which combines a high content of recycled aggregates with pollution busting technology which actually removes harmful Nitrogen Oxides (NOx) from the air. It is predicted that during its lifetime, an average-sized roof covered with EcoLogic tiles could remove an amount of NOx equivalent to that emitted by a modern car driving 100,000 miles.”