EN ISO 13790:2008

Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
   3.1 Time steps, periods and seasons
   3.2 Spaces, zones and areas
   3.3 Temperatures
   3.4 Energy
   3.5 Building heat transfer
   3.6 Building heat gains and recoverable system
        thermal losses
   3.7 Building energy balance
4 Symbols
5 Outline of the calculation procedures
   5.1 Energy balance of building and systems
   5.2 Main structure of calculation procedure
   5.3 Different types of calculation method
   5.4 Main characteristics of the different methods
   5.5 Overall energy balances for building and systems
6 Definition of boundaries and zones
   6.1 General
   6.2 Boundary of the building for the calculation
   6.3 Thermal zones
   6.4 Determination of conditioned floor area, A[f]
7 Building energy need for space heating and cooling
   7.1 Calculation procedure
   7.2 Energy need for heating and cooling
   7.3 Multiple steps to integrate or isolate interactions
   7.4 Length of heating and cooling seasons for operation
        of season-length-dependent provisions
8 Heat transfer by transmission
   8.1 Calculation procedure
   8.2 Total heat transfer by transmission per building
        zone
   8.3 Transmission heat transfer coefficients
   8.4 Input data and boundary conditions
9 Heat transfer by ventilation
   9.1 Calculation procedure
   9.2 Total heat transfer by ventilation per building
        zone - Seasonal or monthly method
   9.3 Ventilation heat transfer coefficients
   9.4 Input data and boundary conditions
10 Internal heat gains
   10.1 Calculation procedure
   10.2 Overall internal heat gains
   10.3 Internal heat gain elements - All methods
   10.4 Input data and boundary conditions
11 Solar heat gains
   11.1 Calculation procedure
   11.2 Overall solar heat gains
   11.3 Solar heat gain elements
   11.4 Input data and boundary conditions
12 Dynamic parameters
   12.1 Calculation procedure
   12.2 Dynamic parameters
   12.3 Boundary conditions and input data
13 Indoor conditions
   13.1 Different modes
   13.2 Calculation procedures
   13.3 Boundary conditions and input data
14 Energy use for space heating and cooling
   14.1 Annual energy needs for heating and cooling,
        per building zone
   14.2 Annual energy needs for heating and cooling,
        per combination of systems
   14.3 Total system energy use for space heating and
        cooling and ventilation systems
15 Report
   15.1 General
   15.2 Input data
   15.3 Results
Annex A (normative) Parallel routes in normative references
Annex B (normative) Multi-zone calculation with thermal
        coupling between zones
Annex C (normative) Full set of equations for simple hourly
        method
Annex D (normative) Alternative formulation for monthly
        cooling method
Annex E (normative) Heat transfer and solar heat gains of
        special elements
Annex F (normative) Climate-related data
Annex G (informative) Simplified methods and standard
        input data
Annex H (informative) Accuracy of the method
Annex I (informative) Explanation and derivation of monthly
        or seasonal utilization factors
Annex J (informative) Worked example; simple hourly and
        monthly methods
Annex K (informative) Flow charts of the calculation
        procedures
Bibliography

ISO 13790:2008 gives calculation methods for assessment of the annual energy use for space heating and cooling of a residential or a non-residential building, or a part of it, referred to as “the building”.This method includes the calculation of:the heat transfer by transmission and ventilation of the building zone when heated or cooled to constant internal temperature; the contribution of internal and solar heat gains to the building heat balance; the annual energy needs for heating and cooling, to maintain the specified set-point temperatures in the building – latent heat not included; the annual energy use for heating and cooling of the building, using input from the relevant system standards referred to in ISO 13790:2008 and specified in Annex A. ISO 13790:2008 also gives an alternative simple hourly method, using hourly user schedules (such as temperature set-points, ventilation modes or operation schedules of movable solar shading).Procedures are given for the use of more detailed simulation methods to ensure compatibility and consistency between the application and results of the different types of method. ISO 13790:2008 provides, for instance, common rules for the boundary conditions and physical input data irrespective of the calculation approach chosen.ISO 13790:2008 has been developed for buildings that are, or are assumed to be, heated and/or cooled for the thermal comfort of people, but can be used for other types of building or other types of use (e.g. industrial, agricultural, swimming pool), as long as appropriate input data are chosen and the impact of special physical conditions on the accuracy is taken into consideration.The calculation procedures in ISO 13790:2008 are restricted to sensible heating and cooling. The energy use due to humidification is calculated in the relevant standard on the energy performance of ventilation systems, as specified in Annex A; similarly, the energy use due to dehumidification is calculated in the relevant standard on the energy performance of space cooling systems, as specified in Annex A.ISO 13790:2008 is applicable to buildings at the design stage and to existing buildings. The input data directly or indirectly called for by ISO 13790:2008 should be available from the building files or the building itself. If this is not the case, it is explicitly stated at relevant places in ISO 13790:2008 that it may be decided at national level to allow for other sources of information. In this case, the user reports which input data have been used and from which source. Normally, for the assessment of the energy performance for an energy performance certificate, a protocol is defined at national or regional level to specify the type of sources of information and the conditions when they may be applied instead of the full required input.