Design Consultation

Designing Healthy Buildings - Prevention Versus Cure

All architects and engineers attempt to design healthy buildings. Do they succeed?

The House of Commons Environment Committee report on indoor pollution in 1991 estimated that 30 percent of office workers in the U.K. have suffered some form of illness as a result of their working environment. They calculated that this may cost the economy £650 million per year in worker illness and lost productivity. The World Health Organisation (WHO) has concluded that up to 30 percent of new and refurbished buildings throughout the world may be affected by Sick Building Syndrome (SBS). Our in-house statistics, compiled from indoor air quality inspections of more than 1100 major buildings around the world since 1981, show the following:

Therefore, there is now an innovative movement in the commercial property industry that pays attention to the issue of SBS at the design and construction stages of a building's life. This approach recognises the benefits of prevention over cure in treating building system ailments. Often such a strategy can head off SBS problems before the building is occupied and an operating history is established. Such foresight also sets the foundation for a permanently healthy building and lessens the chances of SBS problems later during its occupied life.

SBS is usually defined as a condition where at least 15 to 20 percent of a building's occupants exhibit headaches, lethargy, eye irritation, sinus congestion, sore throats, and other general upper respiratory irritation in a pattern that is linked to the building where they work. These symptoms seem to worsen as the day goes on, disappear upon departure from the building at the end of the day, and reappear the following day upon return to the suspected building.

SBS and Building Design

The prime cause of SBS is poor indoor air quality. There are literally thousands of pollutants found in today's indoor environments. New building materials and interior finishing products, common office supplies and equipment, furnishings, maintenance products, pesticides, and even humans themselves all contribute disparate gases, fibres, dusts, compounds, dander, and microbes which when allowed to build up to critical levels in an indoor environment can cause SBS.

After the oil crises of the 1970's, energy costs skyrocketed, causing architects and engineers to design buildings that were more energy efficient. These building designs were practically air tight and provided only one-third the amount of fresh air per occupant previously considered standard. The increased use of synthetic materials within these tightly sealed buildings contributed to the build-up of indoor pollutants.

An environmentally well designed building strikes a balance between the health needs of future occupants and energy efficiency. The owners of the building recognise that the costs of an unhealthy building in terms of future absenteeism and reduced work productivity will far exceed any possible energy savings. Furthermore, these owners have the foresight to realise that this building will be more desirable in today's competitive property market.

Healthy Buildings International

Healthy Buildings International (HBI) is the new breed of environmental consultant that provides architects and engineers with the technical support necessary to design healthy buildings from the ground up. HBI has the extensive field experience and multi-disciplinary expertise necessary to give architects and engineers the advice they need to accomplish this challenging goal. The disciplines covered by our staff include mechanical engineering, architecture, chemistry, industrial hygiene, microbiology, and other scientific fields related to air quality including expertise in lead and radon.

There are many indoor environmental issues HBI considers when conducting a healthy building design study. Much of the analysis centres on the building's mechanical system and its interface with both the outdoor environment and the occupied spaces. In addition, attention must be paid to other less obvious factors that will influence the health of the future occupants. Examples of these are thermal comfort, natural light, noise, staffing densities, occupant profiles, and interior materials.

Healthy Building Desgn Service

A Healthy Building Design Consulting Programme is conducted in three phases as follows:

Phase I - Design Criteria
Meetings with building engineers, architects, and planners enable analysts to collect data and define health objectives for the indoor environment through discussions and analysis of architectural and mechanical drawings. General areas of study include:

» potential site problems and external forces affecting a building
» the effect of the building configuration on pollutant migration from the outside in as well as within a building
» the ability of the building design to control solar heat while allowing for maximum amounts of daylight 
» ventilation systems, their role in indoor air quality, and how to turn them into a remediating tool 
» the maintainability of the HVAC system 
» pollutant source management including material selection and microbial control the building commissioning process.

A comprehensive report is submitted including supporting data, findings, and recommendations.

Phase II - Construction Site Visits
Regular site inspections during construction ensure that there is compliance with all recommendations made at the design stage. General construction practices that might affect air quality during the life of the building are also identified. A report is submitted following each construction site visit.

Phase III - Comprehensive Indoor Air Quality Survey & Ongoing Monitoring
A comprehensive indoor air quality inspection is performed after the building is occupied to establish baseline data. Future reinspections then allow comparison to baseline data as well as to similar buildings in HBI's fieldwork portfolio. As a building is a dynamically changing entity, it is important to monitor a building through seasonal changes, changes in occupant densities, and changes in pollutant sources due to occupants and/or their activities.

The direct and indirect costs of an unhealthy indoor environment to a building owner or tenant will, in our experience, easily dwarf the cost of designing a healthy building from the outset. HBI can provide property developers, architects or engineers with the indoor air quality expertise needed to accomplish this task.