Eco Paint

Paint is used in the construction of homes for purposes of decoration, protection (I.e. painted metal surfaces to prevent corrosion) or functionality (painting a surface white to reflect heat). The use of paint in construction can pose problems for green building as paint itself often contains toxic elements, releases fumes and is made in ways not beneficial to the environment

Paint consists of three main parts, the pigment, the binder and the solvent. The pigment is the part of paint that gives it the colour that is required. This used to be made from materials such as lead which proved to be a health risk and as such has been banned from modern paints. These days paint manufacturers are using different materials to create the pigment with a common one being titanium dioxide which is a much less toxic and is even found in food colourant

The binder of paint is the component responsible for it forming as a film and its adhesion to the painted surface. The binder is also responsible for the finish of the paint affecting things such as glossiness and durability. Binder can be made from natural and synthetic sources such as acrylic, polyurethane and oil based substances.

The main purpose of the solvent in paint is to alter the viscosity. The solvent is volatile and does not form part of the paint film often evaporating away causing the fumes associated with painting. The types of solvent used varies, whilst not technically a solvent water cab be used as well as other materials such as petroleum distillate, ethers, ketone’s and glycol ethers.

The main pollutant paint gives off when in use is Volatile Organic Compounds (VOC’s). VOC’s are released from the paint often while drying from the solvent used. VOC’s can have a huge effect on the internal air quality of a building and the environment and are a major contributor to “sick building syndrome” (a feeling of unwell caused by polluted internal air from various sources such as fumes leaving occupants with head aches and generally feeling ill). In Britain the coatings industry has come up with a labelling system to warn consumers of the VOC content of materials such as paint, these consist of 5 bands and a warning that VOC’s are an atmospheric pollutant. The bands are Minimal – VOC content 0% to 0.29%, Low – VOC content 0.3% to 7.99%, Medium – VOC content 8% to 24.99%, High – VOC content 25% to 50% and Very High – VOC content more than 50%. When considering which paint to use in an environmentally friendly build it is always best to look for the lower VOC rating as these often contain less synthetic materials and will increase the internal air quality of a building reducing the load on ventilation systems.