There is a line of thought that says that if beautiful basic building materials are used sensitively and creatively then there is less need for decoration, in the same way you would probably not want to paint over stylish tiles or a hardwood floor. The paint stripping industry is witness to this. This is all an argument for doing things well in the first place and then the only maintenance is regular cleaning.
Where decoration is needed then there is a steady stream of new companies producing low embodied energythe total amount of energy it takes to make a material (or a building). See more on embodied energy decorative materials with low VOC content. The VOC (volatile organic compounds – such as solvents and driers) issue is serious for both the decorators and the home owner. For the decorator it is a matter of spending much of their working life in close proximity to solvents evaporating from paint, varnish and preservative.
For the occupant the initial few days of new paint is the main problem. However, if you look at any room in a modern house, almost all the surfaces except the actual glass in the windows are composed of plastics which, to a greater or lesser extent, give off VOCsVolatile organic compounds all their life. Floors are often acrylic carpet which gives off VOCs or they are are polyurethane coated. Walls and ceilings are coated with paints containing vinyls, furniture and joinery are coated with polyurethane. There are several different approaches to using more benign decorative materials which relate to the following
- whether and to what extent solvents, dryers and other VOCs are used
- the type of pigments used – natural or manufactured (the point here is that natural pigments have a very limited colour range. Lime based whites have much lower opacity than titanium dioxide).
- whether animal products are used
- whether plastics and plastic adjuncts are incorporated.
There is a limited list of suppliers operating in the UK and it is perhaps best to let them each make their own case for their ingredients.
- Wood Finishes Direct
- Keim Mineral Paints
- Construction Resources carry Holzweg paints
- Holkham Linseed Paints
- Pots of Paint
- Fiddes wood oil
- Auson in Sweden carry Stokholm tar for treating external timber
- Tarinol in Norway also do pine tar based external finishes (and see comment below)
Many of these are German and Scandinavian companies: the mainstream UK manufacturers are dominated by two main groups who have done little to promote green decorating materials.
The purpose of these coatings is to protect timber from rain and sun but at the same time allow small amounts of moisture to escape from the timber without breaking the coating (as often happens with normal paint). This is achieved by the coating being able to ‘breathe’. The greenest coatings use natural or water-based solvents rather than petrochemical ones. It is important to use exterior ones for outdoor work as they tend to contain opaque pigments to block sunlight.