External wall insulation refers to adding insulation materials to the exterior walls of a building to improve its thermal performance. This can involve installing a range of materials, such as expanded polystyrene, mineral wool, or polyurethane foam. The insulation is typically covered by a protective layer, such as render or cladding, which helps to improve the durability of the insulation and provides an attractive finish to the building's exterior. Thermal insulation walls are walls that have been designed and constructed with the primary purpose of reducing the transfer of heat from one side of the wall to the other. This can involve the use of insulation materials and techniques such as double-glazing or the incorporation of air gaps. The goal of thermal insulation walls is to reduce energy consumption by improving the energy efficiency of the building envelope. This can help to lower heating and cooling costs, improve indoor comfort, and reduce the building's carbon footprint.