What means Building Science?
The increasing trend of innovative building practice coupled with the rising tide of emerging associated professional roles such as 'building scientist' and ‘building engineer' makes the question of what building science is of interest and relevance today.

Definition
Building science could be termed ‘the science of building performance’ and one that is particularly dependent on the measurement of it. Without measurement, science  is akin to philosophy and based purely on assumptions and hypotheses.
Building science  involves a range of disciplines, founded upon the school core subjects of physics, chemistry instrumentation  and biology and integrates higher education subjects including architecture and interior design, a broad range of engineering disciplines (civil engineering,  structural engineering, seismic engineering,  geotechnical engineering, mechanical engineering, electrical engineering,  acoustic engineering and fire engineering), construction technology, instrumentation, environmental design, climatology, economics, political science, behavioral sciences and other life sciences such as ecology.
Building physics and applied physics are terms that overlap with it. Building physics is sometimes used to mean building science but usually only focuses on the interplay of heat, air, and moisture flows within and across a building enclosure.
Some argue that it is more associated with a building envelope or enclosure than with mechanical and electrical building systems but others suggest it requires understanding of these as well as their effects on heat, air and moisture flows.  It is particularly concerned with quantifiable methodology but also concerned with building:

  • policies (codes and standards)
  • planning and design
  • preservation and conservation
  • demolition and recycling
  • construction and commissioning
  • forensics, rehabilitation, restoration, retrofit
  • testing and validations
  • facilities management
  • life cycle
  • occupancy

Above all it represents the detailed design, measurement, analysis and control of physical phenomena concerning buildings.

Building Scientists
There is no certification or licensing associated with building science per se, although in the US there is a non-profit National Institute of Building Sciences (NIBS) with a membership scheme.
The UK based Chartered Association of Building Engineers (CABE) founded as the Incorporated Association of Architects and Surveyors has an accredited membership scheme open to members worldwide.

Evolution
Modern building science is a construct in the history of building innovation. It has arisen following assessment of the building failures encountered when attempts to innovate were made without applying its principles. It is often fully appreciated after the occurrence of building performance problems, or worse, after failures, rather than at the earlier planning and design stages.
There was no need for it in the past.  Successful building precedents were copied and passed on from one generation to the next but as this happened little advancement was made towards the high performance buildings sought today.
Today it includes the detailed building design, analysis and control of many areas applying innovation including:

  • building materials and building envelope
  • heating, ventilation and air conditioning (HVAC) systems and passive strategies
  • natural and artificial lighting
  • acoustic protection
  • indoor air quality
  • fire protection
  • renewable energies

Innovation is not simply a process resulting from trial and error approach that relies on refining past precedents but instead a significant departure from traditional practice for it depends on scientific methods. Attempts are being made to use building system models and to apply scientific empirical techniques to provide effective solutions to innovation design problems.
However it should be recognized that measuring instruments like pull testers, thermometers, hygrometers, and others have been the most suitable tools for validating and improving engineers work for a long time and continue to be so today.

Purpose
Some describe how the purpose of building science is
to provide predictive capability to optimize building performance, to understand or prevent building failures and to ensure that building systems work together to minimize issues related to moisture, durability, indoor air quality, thermal, acoustic or visual comfort” ~Wikipedia

Benefits
Building science provides the language, framework, and systems thinking to make our buildings resource and energy efficient, comfortable and durable in a changing environment with ever increasing demands for this. It also has the additional benefits of:

  • improving building performance in terms of protection against extreme weather events such as hurricanes, earthquakes and floods.
  • enhancing performance  for  materials (including stone, stucco, gypsum, concrete, tiles and metal sheets)
  • minimising negative issues associated with the interdependence of building enclosures with mechanical and electrical systems and occupancy
  • allowing the response of structures subject to earthquakes to be monitored facilitating improved seismic design.
  • facilitating the understanding of the sources of indoor environmental contaminants and controlling them to help prevent or resolve building related user negative health and comfort issues.
  • integrating environmental design features that consider future resources and conditions and facilitating the design of zero energy buildings (zero carbon, net zero energy or carbon neutral buildings).

The practical outcomes of building science is both qualitatively reflected in architectural building envelope detailing and quantifiably measurable via the long term performance of building