After World War II, new houses were rapidly built in Germany to accommodate the growing population. Studies of these new houses found an unusual patterns of illnesses. The rapid construction had given materials insufficient time to outgas various volatile organic compounds (VOCs), and these VOCs instead harmed the occupants. The illness is also attributable to problems with the electrical systems of the homes.
From these discoveries a study began to catalog and characterize these effects. What emerged was a Standard of Baubiologie Method of Testing, with recommended threshold guidelines for sleeping areas, where one is most susceptible and spends a large amount of time.
Building on from this, more principles for healthy buildings were developed under the umbrella name of “building biology”.
The Institute of Building Biology + Sustainability (IBN) was founded in 1983. The IBN grew out of the work of the “Work Group Healthy Building + Living” since 1969  and the former “Institute of Building Biology” since 1976.
Building Biology Institutes are now all around the world. In 1987 the International Institute of Building Biologie and Ecology (IBE) was founded in the US, in 1990 the Building Biology and Ecology Institute of New Zealand (BBE).
What is Building Biology
Homes or dwellings can be seen as organisms. The term third skin accurately describes the intimate relationship between humans and their living space. It vividly illustrates how closely we are interrelated with our living environment and also in how many ways we are dependent on it.
We define building biology as the study of the holistic interrelationships between humans and their living environment. 
Building Biology advocates buildings that contribute to the occupant’s health of spirit, mind and body and have a low impact on the environment.
The German website of the IBN has 25 building biology principles: 
The 25 Principles of “Baubiologie” (Building Biology)
- Building site without natural and human-made disturbances
- Residential homes away from sources of emissions and noise
- Low-density housing with sufficient green space
- Personalized, natural, human- and family-oriented housing and settlements
- Building without causing social burdens
- Natural and unadulterated building materials
- Natural regulation of indoor air humidity through humidity-buffering materials
- Low total moisture content of a new building that dries out quickly
- Well-balanced ratio between thermal insulation and heat retention
- Optimal air and surface temperatures
- Good indoor air quality through natural ventilation
- Heating system based on radiant heat
- Natural conditions of light, lighting and color
- Changing the natural balance of background radiation as little as possible
- Without human-made electromagnetic and radiofrequency radiation exposure
- Building materials with low radioactivity levels
- Human-oriented noise and vibration protection
- With a pleasant or neutral smell and without outgassing toxins
- Reduction of fungi, bacteria, dust and allergens as low as possible
- Best possible drinking water quality
- Causing no environmental problems
- Minimizing energy consumption and utilizing as much renewable energy as possible
- Building materials preferably from the local region without promoting exploitation of scarce and hazardous resources
- Application of physiological and ergonomic findings to interior and furniture design
- Consideration of harmonic measures, proportions and shapes
The New Zealand website of the BBE, the Building Biology and Ecology Institute, has extended those 25 principles slightly to make make clear that there is a wider connection of us and our building with the neighbourhood and environment: 
We have divided the principles into 3 groups with 10 principles each:
How does it compare
Building Biology is a holistic approach to building design. Many other “systems” and schemes tend to look at certain limited aspects only.
For example the Green Building Council does not look at neighbourhoods, cultural implications or healthy materials, neither at shape, volume and colours, not at EMF and EMR.
The Living Building Challenge is probably a closest match as it includes “Beauty” in design as well and shape and volume, however still falls short on EMR.
Building Biology is an idea and has guidelines, but is not a “rating scheme” that you can comply with, there is no certification. Which, on the other hand, can make it more flexible and can lower cost.
Über uns, retrieved 2015-06-08 from http://www.baubiologie.de/institut/
English Flyer, retrieved 2015-06-08 from http://www.baubiologie.de/downloads/eng-flyer.pdf
The 25 Principles of “Baubiologie” (Building Biology), retrieved 2015-06-08 from http://www.baubiologie.de/international/25-principles-baubiologie-building-biology/
A sustainable, healthy and harmonious built environment for all, retrieved 2015-06-08 from http://www.bbeorgnz.squarespace.com