What is the definition of thermal insulator?
Thermal insulation is the reduction of heat transfer (i.e. the transfer of thermal energy between objects of differing temperature) between objects in thermal contact or in range of radiative influence. The insulating capability of a material is measured as the inverse of thermal conductivity (k).
A thermal bridge, also called a cold bridge or heat bridge, is an area or component of an object which has higher thermal conductivity than the surrounding materials, creating a path of least resistance for heat transfer. Thermal bridges result in an overall reduction in thermal resistance of the object.
- Rigid panel insulation is made from fibrous materials (fiberglass, rock and slag wool) or from plastic foam. They are sometimes sold in sections designed to fit tightly in standard wall cavities.
- Polystyrene is classified according to DIN4102 as a "B3" product, meaning highly flammable or "Easily Ignited." As a consequence, although it is an efficient insulator at low temperatures, its use is prohibited in any exposed installations in building construction if the material is not flame-retardant.
- The burning of polystyrene releases styrene gas which can effect the nervous system. Also, as it usually burns with a sooty flame, this indicates combustion isn't complete and a complex mixture of toxic chemicals can produced by the relatively low temperature of a backyard burn.
A thermal break or thermal barrier is an element of low thermal conductivity placed in an assembly to reduce or prevent the flow of thermal energy between conductive materials.
Updated: 2nd October 2019