This document specifies procedures and conditions to enable the heat flow in water-based and electrical surface heating and cooling systems to be determined relative to the medium differential temperature for systems. The determination of thermal performance of water-based surface heating and cooling systems and their conformity to this document is carried out by calculation in accordance with design documents and a model. This enables a uniform assessment and calculation of water-based surface heating and cooling systems.

The surface temperature and the temperature uniformity of the heated/cooled surface, nominal heat flow density between water or electrical heated layer and space, the associated nominal medium differential temperature, and the field of characteristic curves for the relationship between heat flow density and the determining variables are given as the result.

This document is applicable to water-based embedded surface heating and cooling systems in residential, commercial and industrial buildings. This document is also applicable for electrical heated embedded systems. The methods apply to systems integrated into the wall, floor or ceiling construction without any open air gaps. It does not apply to ceiling mounted panel systems with open air gaps which are not integrated into the building structure.