Indoor Air Quality in Commercial Buildings

About one-half of all commercial buildings in the US were built during or after the 1970s, the decade during which energy conservation became a national concern and priority. In response to changes in building design, construction, operation and maintenance to save energy as well as the increasing use of synthetic building materials, the quality of indoor air diminished and building occupants began to report building-related symptoms (BRS), such as headache, eye irritation, nose and throat irritation, and general fatigue, to name a few examples.

Since then, results of numerous studies have demonstrated that BRS can adversely affect productivity and occupant well being. Even so, the economic return on investing in good indoor air quality (IAQ) within the commercial building market remains a tough sell.

Commercial buildings comprise nearly 70 percent of all buildings in the US. In addition to office buildings, this category includes retail establishments (such as stand alone stores, malls and strip shopping centers), public assembly (such as museums and entertainment facilities), places of worship, police and fire stations, warehouse and storage, and other services.

Designing and constructing a commercial building that provides acceptable IAQ, whether it is new construction or renovation of an existing structure, is a process during which each step is interdependent on those coming before and after. Failure in one step risks failure in subsequent steps and ultimately in the building itself. The lack of communication and coordination among the design professionals and construction team, and between the general contractor and subcontractors, often compounds the risk of failure, especially if the project gets behind schedule. Once occupied, proper operation and maintenance of a building are also of prime importance, as poorly operated and maintained buildings are prone to more IAQ problems. Another inherent risk is the lack of expertise and understanding of how the interrelationship of numerous factors can contribute to poor IAQ, both during design and construction and after occupancy.

Early studies demonstrated that ventilation and lack of environmental control (temperature and humidity) in buildings caused a large percentage of IAQ problems in office buildings. Recent studies, however, show that elevated pollutants and odors also contribute significantly to poor IAQ. Indoor air quality in commercial buildings can also be affected by the buildings themselves, the activities and processes within the building, outdoor environmental conditions and occupant activities.

Green or sustainable building, a rapidly growing movement in the primarily commercial building market, focuses on preserving both the indoor and outdoor environments through water and energy conservation measures and careful selection of building sites, building design, recycled materials, lighting, and materials, finishes and furnishings that emit low amounts of volatile organic compounds (VOCs). As of the end of 2003, US Green Building Council's Leadership in Energy and Environmental Design (LEED™) certified buildings accounted for 139 million sq. ft. (up from 51 million in 2001) of the commercial building market, which translates into five percent of the new commercial building starts in the US by square footage.