Sick Building Syndrome

The correlation between our health, levels of mould, humidity, chemicals and particulates in the air is well documented. Research throughout the 1990’s around the world (Korea, NZ, Germany and the US) has recognised the impact of indoor air quality on our health and conned the phrase ‘sick building syndrome’.

Is Sick Building Syndrome something we need to be concerned about in Australia, in our homes or our workplace? Perhaps it is. This article considers the issues associated with ventilation and presents suggestions for better ventilating our homes.

Ventilation, refers to the movement and change of air within a building, this usually involves the replacement of stale air with air from outside the building. The main purpose of which is to maintain and improve indoor air quality. Ventilation is also one of the most effective ways of reducing the level of allergens, in the air, this is critical for those people who experience symptoms associated with asthma, or chemical sensitivities. What can you do to consider the movement and changing of the air within your home and provide for better ventilation?.

Ideally when we design and build our home we consider the principles of natural air movement, which is driven by and capitalises on temperature and pressure differences. Our choice of building materials and design are fundamental to capitalizing on natural ventilation options like.

• Cross-ventilation - the movement of air horizontally across a floor. This is usually wind driven and affected by open windows/doors.
• Stack effect - the movement of air upwards. Remember the adage ‘hot air rises’!

However the real world and the ideal world are rarely mirror images of each other. In fact modern building techniques tend toward well sealed and energy efficient building envelopes. These buildings typically do not circulate air well or often enough to maintain ‘healthy’ indoor air.

The British based, Building Research Establishment has identified that ideally the air within a building should completely change at least 2 - 3 times per hour, to ensure a healthy indoor environment.

Recognising the frailties of nature, modern building techniques, and density of urban living (and our desire to keep out noise and pollutants) can we use mechanical means to better ventilate our homes? The simple answer is YES – mechanical ventilation refers to the movement of air which is driven by fans which will either.

• Force air into a building (supply fans).
• Move air through a building (recirculating fans)
• Remove air from a building ( extraction fans)
• Or any combination of these features.

The most advanced systems are designed for the whole home and also include features that may filter air, regulate humidity and involve heat recovery. These systems are also referred to as MVHR systems (mechanical ventilation and heat recovery systems).

What are the simple suggestions, which will help you better manage air quality and movement in your home?.

• Manage moisture levels. Moisture and humidity (the invisible vapour/water in the air) directly affect mould, dust mite and pollen levels in our home.
• Always add extraction fans in wet areas, which exhaust moisture external to the roof cavity.
• Operate these fans until all the moisture has been drawn from the air not just until you exit the room.
• Consider opportunities to create some degree of natural ventilation. This can be as simple as opening a window or door.
• If your home is in a dense inner city zone and you want to block out noise and pollutants, investigate the range of MVHR systems in the market. This technology will ensure you do ventilate adequately.
• Consider single room ventilation units (fans) in rooms where family members with asthma or allergies spend time.

To improve the air quality in and around your home, seek further information on this site about Dehumidifiers, Sub-floor ventilators and Roof ventilators.