Solvent-based products are undoubtedly less tricky to apply and spread more easily. On some types of wood they also combat the escape of the wood extracts which would stain it and they avoid the fibres lifting and roughening the surface. The main feature of solvent-based products is that they can be applied in a wider range of temperatures and humidity levels compared to water-based products. However, this type of product is ever more subject to constraints associated with the emission of volatile substances, leading, in the EU, to a constant demand to reduce their environmental impact. Today’s water-based products embody evolutions in technology and quality that put them on an even footing with solvent-based products. Indeed the weather-resistance of some resins is actually better and the emission of harmful substances is reduced to the minimum. The most popular features are their extremely short drying-time, making it possible to apply more than one coat in a day, and their very faint smell, making this type of product ideal for indoor use. It could be said that opting for a water-based product is the more eco-friendly choice. However, it can be difficult to work with these products in temperatures that are too high or too low, or where there is high humidity and therefore, while the best product is undoubtedly the eco-friendly one, the choice does still depend on the constraints on its use.