The main difference between solid and engineered wood flooring is that a solid board is a single piece of solid timber, while an engineered board is made up of several layers of timber. Solid wood flooring can be sanded down and refinished repeatedly. Engineered wood flooring is a much more stable floor with a robust construction, resistant to environmental changes, suitable for environments with large changes in temperature and humidity, such as bathrooms, utility rooms, or kitchens.