Building science focuses on creating buildings that function well. It helps ensure that buildings can withstand harsh environments, such as extreme temperatures, high winds, heavy precipitation and seismic activity.
It also protects building owners from costly repairs and occupant discomfort caused by poorly performing materials or systems. The discipline draws from a wide range of engineering disciplines and physics.
Energy Efficiency
The energy used to operate buildings accounts for a sizeable portion of the world’s total energy consumption. Energy efficient building construction and operation can significantly reduce these consumption levels, as well as the associated environmental impacts such as greenhouse gas emissions and climate change.
Achieving energy efficiency in buildings requires a multidisciplinary approach to design, construct, and operate building systems. This is the role of contemporary building science, which offers a variety of sophisticated design tools and testing protocols, as well as performance simulation/validation methods.
For example, a building scientist may use sensors to track air quality and temperature in a building, then take that data and integrate it into a model of the building, resulting in a design that will optimize the building’s indoor environment. Building scientists also help construct buildings using more sustainable materials and practices.
In addition to new construction, building science is an important component of the renovation of existing buildings and structures. This is because the understanding of the properties of building materials and their behavior over time is vital for ensuring that buildings remain safe, healthy, and functional.
For example, if the integrity of a building’s foundation is compromised, it might collapse. A building scientist would use his/her knowledge of physics to ensure that the integrity of the structure is maintained throughout its lifespan, even during a major renovation.
Moisture Resistance
Moisture resistance is a key component of energy-efficient and healthy buildings. A building’s materials need to resist moisture penetration, transport and condensation to protect its occupants and maintain the integrity of the assembly. Moisture damage often leads to rot, mold growth and corrosion of metals. These issues reduce a structure’s thermal performance, increase its maintenance costs and negatively impact the health of its occupants.
Moisture-related problems usually start when water moves into some part of a building that shouldn’t be wet, exceeding the safe moisture content limit for moisture-sensitive materials. Sources of moisture include rainfall, groundwater, plumbing water and indoor and outdoor sources of humidity.
The ability of materials to resist moisture largely depends on the moisture management strategies used, which are tailored to the local climate. For example, in arid climates, moisture control involves preventing water infiltration during rain events and managing humidity levels with strategies like dehumidification.
For humid regions, a good moisture strategy includes an exterior vapor retarder to prevent warm moist air from reaching cold surfaces within the wall assembly where condensation can occur. This vapor retarder is necessary in most wood and metal framed walls, especially where thermal bridges exist.
Indoor Air Quality
As humans spend over 85-90% of their time indoors, a building’s IAQ has a major impact on people’s health. Poor air quality leads to health problems, including respiratory issues, headaches, cardiovascular diseases and cancers. It can also cause work-related illnesses such as fatigue, drowsiness and reduced concentration. Other issues include increased stress, loss of productivity and a higher risk of fires or injuries.
The quality of air in a space can be determined by measuring its contaminants, toxins and odors. Good air quality is achieved when spaces are adequately ventilated (with outside air) and kept clean of pollutants brought into the space or off-gassed within the building. For example, ETS – secondhand smoke – is a known pollutant that can be controlled by restricting smoking in buildings.
Most developed countries consider the IAQ of their building environments during the design phase and follow appropriate regulations. However, this is not the case in developing and underdeveloped countries where poor IAQ disproportionately affects children, women and elderly people. Recent scientific studies have explored the different pollutants that may impact IAQ. Some may produce immediate symptoms, while others such as radon and asbestos may not cause any immediate symptoms but can lead to cancer over long periods of exposure. The odours and chemicals released from newly installed flooring, paints and caulks/seals are also known to negatively impact IAQ.
Building Envelope
The building envelope—the walls, windows, roof, and foundation—is the primary boundary between the inside of a structure and the outside environment. Its performance affects how much energy is required to heat, cool, and ventilate a building as well as indoor comfort and air quality.
Getting the building envelope right is a complex task that requires a holistic approach. It’s not enough to replace one component at a time to improve efficiency. Rather, all of the elements of the envelope—including cladding, control layers, structural framing, and insulation—must work together to achieve a high-performance building.
A poorly optimized building envelope results in energy loss, which increases operating costs and contributes to greenhouse gas emissions. By improving insulation, sealing leaks, and using energy-efficient materials, builders can significantly reduce building energy consumption and operational costs.
Additionally, the proper design and construction of the envelope can help reduce stress and wear on HVAC systems, further lowering operating costs. In addition, a tight building envelope enhances indoor comfort by regulating temperature, reducing noise infiltration, and preventing moisture buildup—a significant threat to the structure and integrity of a building.
Local climate plays a significant role in determining the type of materials and how they are placed in the envelope. For example, a cold climate demands a more robust envelope that can withstand higher winds. Additionally, some locales have requirements for curb appeal that need to be taken into consideration when designing the building envelope.