Importance of Indoor Environment Quality

Indoor Environment Quality (IEQ) is an assessment of the internal environments within a residential or commercial building and whether that environment will promote comfort, health, well-being, and productivity. When completing an SDA or SMP, an IEQ assessment will be considered, with the following factors assessed:

  • Cross Flow Ventilation
  • Orientation
  • Shading
  • Daylight
  • Thermal comfort

Cross Flow Ventilation

Cross Flow Ventilation is the controlled movement of air through a building and is important to avoid stagnant and unhealthy air build up, maintain levels of thermal comfort and provide passive cooling opportunities. Cross Flow Ventilation is assessed via determining the placement of breeze paths between two openings (including windows, skylights and external doors) on either opposite or adjacent walls.

Orientation

Orienting a building correctly can have a dramatic effect on the indoor environment quality, particularly for residential buildings. Positioning communal and well frequented spaces such as the kitchen, dining and living rooms to the north can provide these areas with passive heating during summer, abundant light and overall provide for a more enjoyable atmosphere. Positioning utility rooms such as laundries to the east/west can provide buffer zones during the hot summer months.

Shading

Effective shading is critical to maintain a comfortable indoor temperature year-round. Correctly shading northern windows and walls can increase passive heating during winter and decrease unwanted heat gains during summer. As a general rule, fixed horizontal shading (such as eaves/pergolas) is the best option for shading northern orientations.

Western and eastern orientations are addressed slightly differently due to lower angles of the sun in summer, and considerable less exposure during winter. Vertical, operable shading (such as external track blinds) provide the best opportunity for reducing heat gain in summer while increasing the amount of light and heat received during winter.

Daylight

Adequate levels of daylight to living rooms and bedrooms can have a profound effect on wellbeing due to the daylight giving the occupants a sense of time and place, helping them to regulate the body’s natural rhythms.

Daylight is assessed in a number of ways including using the BESS built in calculation tools, Green Star Hand calculations, and daylight modelling software.

Thermal Comfort

Thermal comfort refers to comfortable indoor temperatures for the building and seeks to minimize artificial heating/cooling from sources such as air conditioning. Appropriate levels of insulation, double glazing and utilizing passive design principles will help to ensure that the building maintains comfortable indoor temperatures year-round.

Summary

The above is just a snapshot of some of the factors that are considered when assessing the Indoor Environment Quality of a building. When enjoying a building with a high degree of indoor environment quality, it’s easy to see why this is such an important aspect to consider in the design and construction of any project. If you have any questions regarding IEQ and your project, please feel free to reach out to the team at Green Rate for advice.

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