Peter Sotherton of Teknos GBI discusses the development of more sustainable exterior paints and coatings, and how they can help client organisations ensure they are acting responsibly when it comes to the environment
Paints and finishes are an important part of the sustainability jigsaw. Good quality performance paints enhance and protect buildings, helping to maintain and extend the life of materials, saving on replacement and the consequent use of natural resources. These are particularly important considerations when specifying paints and coatings for exterior use; for example, those used to protect timber windows, doors, conservatories and cladding. Oil-based paints would traditionally have been the first choice, but these involve the production of toxins, which can harm humans. The most obvious indication of the damage conventional paints can do is the odour they give off due to VOCs (volatile organic compounds). VOCs rank high on the list of concerns when considering paints, although they are found in other materials such as domestic cleaning products and furniture. These chemical compounds vaporise, so the fumes affect those applying the products as well as those occupying the building, because ‘off-gassing’ continues, even after the paint has been applied. This unseen hazard can result in allergic reactions, nausea, dizziness and headaches; VOCs are also linked to cancer. According to the World Health Organisation, professional decorators have a 40 per cent greater risk of lung cancer.
Following regulations to minimise, monitor and control the harmful effects of VOCs in 2007, the levels in paints have been steadily reduced, and products must be compliant in formulation and labelling. This does not make all paints equal; some are much more sustainable than others, both in their chemical content and performance in use. Labels such as eco, green and organic are often used in the marketing of paints, but cannot be relied upon when specifying products, as there are no set standards for defining these labels. Manufacturers that are committed to providing sustainable and innovative solutions offer ranges that include water-borne paints. These are low VOC and, unlike traditional oil-based products, do not contain heavy metals and other toxins. They also have a lower carbon footprint and embrace manufacturing processes that have a lower environmental impact. True sustainability goes much deeper than the end product; it should permeate the entire business. Manufacturers that take their responsibilities seriously have sustainability integrated within their business model. Products must use fewer and more sustainable resources; in turn meaning increased use of renewable and secondary raw materials and the analysis of life-cycle impacts.
This means taking responsibility for the entire value chain, from procurement to delivery. Defining and comparing energy and carbon emissions is far from straightforward and the various methodologies and data used can produce a wide range of embodied values for any given material or process. To overcome these problems, Environmental Product Declarations (EPDs) offer a standardised way of measuring paint’s environmental impact. The declarations cover the life stages from cradle-to-gate and include information on raw material acquisition, energy use and efficiency, raw material substances and chemicals used, and the environmental impacts related to emissions and waste for a specific product range. High quality, sustainable water-borne paints compare favourably with traditional oil-based products in terms of performance, with low VOC levels and little or no unpleasant odour. When used on external joinery they can offer superior durability. Due to the flexibility of the paint film, they are less likely to crack and have excellent resistance to the weather and UV rays, retaining their colour and surface appearance over time.
In the past, some water-borne paints have been criticised for being difficult to apply, with poor coverage and slow drying times, but this need not be the case. The latest generation of innovative products has solved these problems while also embracing the trend for strong colours. This is achieved through the use of high-grade raw materials, including superior pigments and binders, and a large proportion of ‘solids.’ Various sheen levels are offered today with a high gloss finish available that is comparable with the appearance of traditional oil-based products.
These water-borne paints are easy to use and have a good flow and even spread, while the number of coats required is reduced. All of these factors help make the process of application easier, whether with a brush, roller or spray. Where necessary, products may be thinned with water. Decorating equipment is easily cleaned ready for reuse using water and a suitable detergent – no solvent cleaner is needed. It must never be forgotten that the environmental impact of paint is part of the environmental impact of a whole building. As with any product, the key to its specification is remembering that the least sustainable product of all is one which fails to work, or, worse still, makes the people using it or living with it unwell.
Peter Sotherton is business development manager at Teknos GBI; a leading supplier of water-borne coatings