BS EN ISO 13370:2007

BS EN ISO 13370:2007 Thermal performance of buildings. Heat transfer via the ground. Calculation methods

BS EN ISO 13370 provides methods of calculation of heat transfer coefficients and heat flow rates for building elements in thermal contact with the ground, including slab-on-ground floors, suspended floors and basements.

It applies to building elements, or parts of them, below a horizontal plane in the bounding walls of the building situated:

• For slab-on-ground floors, suspended floors and unheated basements, at the level of the inside floor surface

• For heated basements, at the level of the external ground surface.

BS EN ISO 13370 includes calculation of the steady-state part of the heat transfer (the annual average rate of heat flow) and the part due to annual periodic variations in temperature (the seasonal variations of the heat flow rate about the annual average). These seasonal variations are obtained on a monthly basis and, in general, BS EN ISO 13370 does not apply to shorter periods of time.

Contents of BS EN ISO 13370:

• Foreword
• Introduction
• Scope
• Normative references
• Terms, definitions, symbols and units
• Terms and definitions
• Symbols and units
• Methods of calculation
• Thermal properties
• Thermal properties of the ground
• Thermal properties of building materials
• Surface resistances
• Internal temperature and climatic data
• Internal temperature
• Climatic data
• Thermal transmittance and heat flow rate
• Thermal transmittance
• Thermal bridges at edge of floor
• Calculation of heat flow rate
• Effect of ground water
• Special cases
• Parameters used in the calculations
• Characteristic dimension of floor
• Equivalent thickness
• Calculation of thermal transmittances
• Slab-on-ground floor
• Suspended floor
• Heated basement
• Unheated basement
• Partly heated basement