---
title: "Building performance simulation"
chunk: 1/3
source: "https://en.wikipedia.org/wiki/Building_performance_simulation"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T13:59:10.370223+00:00"
instance: "kb-cron"
---

Building performance simulation (BPS) is the replication of aspects of building performance using a computer-based, mathematical model created on the basis of fundamental physical principles and sound engineering practice. The objective of building performance simulation is the quantification of aspects of building performance which are relevant to the design, construction, operation and control of buildings. Building performance simulation has various sub-domains; most prominent are thermal simulation, lighting simulation, acoustical simulation and air flow simulation. Most building performance simulation is based on the use of bespoke simulation software. Building performance simulation itself is a field within the wider realm of scientific computing.

== Introduction ==
From a physical point of view, a building is a very complex system, influenced by a wide range of parameters. A simulation model is an abstraction of the real building which allows to consider the influences on high level of detail and to analyze key performance indicators without cost-intensive measurements. BPS is a technology of considerable potential that provides the ability to quantify and compare the relative cost and performance attributes of a proposed design in a realistic manner and at relatively low effort and cost. Energy demand, indoor environmental quality (incl. thermal and visual comfort, indoor air quality and moisture phenomena), HVAC and renewable system performance, urban level modeling, building automation, and operational optimization are important aspects of BPS.
Over the last six decades, numerous BPS computer programs have been developed. The most comprehensive listing of BPS software can be found in the BEST directory. Some of them only cover certain parts of BPS (e.g. climate analysis, thermal comfort, energy calculations, plant modeling, daylight simulation etc.). The core tools in the field of BPS are multi-domain, dynamic, whole-building simulation tools, which provide users with key indicators such as heating and cooling load, energy demand, temperature trends, humidity, thermal and visual comfort indicators, air pollutants, ecological impact and costs.
A typical building simulation model has inputs for local weather such as Typical Meteorological Year (TMY) file; building geometry; building envelope characteristics; internal heat gains from lighting, occupants and equipment loads; heating, ventilation, and cooling (HVAC) system specifications; operation schedules and control strategies. The ease of input and accessibility of output data varies widely between BPS tools. Advanced whole-building simulation tools are able to consider almost all of the following in some way with different approaches.
Necessary input data for a whole-building simulation:

Climate: ambient air temperature, relative humidity, direct and diffuse solar radiation, wind speed and direction
Site: location and orientation of the building, shading by topography and surrounding buildings, ground properties
Geometry: building shape and zone geometry
Envelope: materials and constructions, windows and shading, thermal bridges, infiltration and openings
Internal gains: lights, equipment and occupants including schedules for operation/occupancy
Ventilation system: transport and conditioning (heating, cooling, humidification) of air
Room units: local units for heating, cooling and ventilation
Plant: Central units for transformation, storage and delivery of energy to the building
Controls: for window opening, shading devices, ventilation systems, room units, plant components
Some examples for key performance indicators:

Temperature trends: in zones, on surfaces, in construction layers, for hot or cold water supply or in double glass facades
Comfort indicators: like PMV and PPD, radiant temperature asymmetry, CO2-concentration, relative humidity
Heat balances: for zones, the whole building or single plant components
Load profiles: for heating and cooling demand, electricity profile for equipment and lighting
Energy demand: for heating, cooling, ventilation, light, equipment, auxiliary systems (e.g. pumps, fans, elevators)
Daylight availability: in certain zone areas, at different time points with variable outside conditions
Other use of BPS software

System sizing: for HVAC components like air handling units, heat exchanger, boiler, chiller, water storage tanks, heat pumps and renewable energy systems.
Optimizing control strategies: Controller setup for shading, window opening, heating, cooling and ventilation for increased operation performance.