Indoor Environment and Energy Use in Residential Buildings
On average, people spend more than 50 percent of their time in their homes, and as a result, energy use in residential buildings is greater than in commercial buildings. With this in mind, ASHRAE is focused on increasing our activities to better serve the residential marketplace as we continue working to build a more sustainable future.
That may come as a surprise, because many believe ASHRAE only looks at issues related to commercial buildings. But, in fact, ASHRAE has long been a participant in critical aspects of residential building performance, from fundamentals on heat transfer and equipment sizing to human comfort.
For example, we have technological offerings like ASHRAE Standard 62.2 that address the indoor air quality needs in homes. ASHRAE also has a renewed effort on ASHRAE Standard 90.1 to better address residential building energy use.
The first step in this focused charge into the residential space was forming a committee under the Technology Council—the “Residential Buildings Committee.” This committee is in charge of extending ASHRAE’s vast industry knowledge and presence into the residential sector.
In fact, several initiatives are already underway.
We are establishing an ASHRAE conference with a strong residential focus, which will be held every three years. Another way we are working toward improving the residential built environment is through ASHRAE’s Green Guide publication. This publication has been revised to include specific content on residential buildings. Additionally, the development of the first residential building design guide focusing on multi-family buildings has begun.
While commercial buildings may look quite similar around the world, there are huge differences in residential buildings in both design and building technologies. Therefore, it is impossible to establish guidelines that cover the breadth of residential buildings worldwide. However, we are facing this challenge head on. One way we will extend this effort is by enabling regions or chapters to develop locally-specific guides with support from our technical committees, standard committees and headquarters.
Another important issue with residential buildings is the significant influence of the user. Occupant behavior in homes will significantly influence both the indoor environment and energy usage. We need to obtain a much better understanding of occupant behavior so we can address it in design, control and user feedback.
No matter what we do, we will always have some sources of indoor air pollutants in both the residential and commercial indoor environment. The main source is in fact people themselves. This means we always need ventilation. This is the primary technology that provides an acceptable indoor air quality.
It is also important to note that while people, for example, eat one kilogram of food and drink two liters of water every day, we do breathe about 15 kilograms of air. This is a staggering figure and clearly shows the importance of the quality of the indoor environment.
The highest priority is to reduce the emission of substances into the indoor environment. For homeowners and multi-family building owners, this means working with those involved in constuction to carefully select the best matertials, furnishing, carpets, paints, and other materials to help limit emissions. By using low-emitting materials, the need for ventilation may be reduced and air quality may be improved.
Heat recovery is also a very important technology for residential ventilation systems. This technology may recover 80 percent of energy usage for ventilation.
In some cities, the outdoor air quality is not acceptable for ventilation. In these cases, it may be more efficient to use filtration of the outdoor air and/or use air cleaning technologies. It also points to the importance of ensuring air filters are regularly being changed and an HVAC audit is being conducted annually.
ASHRAE and our more than 56,000 members worldwide are working tirelessly to improve indoor air quality in both the commercial and residential sectors. Through this work, we are continuously creating and advancing toward a future where the built environment is healthier, more comfortable and more energy efficient, which will, in turn, produce a more sustainable world for future generations.