# Indoor Environment Quality 3.2 Thermal Comfort - External Shading
# Applies to
Single dwellings and multi-dwelling (dual occupancy, townhouse, villa unit etc)
# Objective
To provide comfortable indoor spaces and reduce energy needed for heating and cooling
# Summary
Points are awarded where appropriate external shading is provided to all east, west and north facing habitable room windows.
# Documentation & evidence required
- Reference to floor plans and elevations showing shading devices.
# Other Considerations
For north facing glazing, fixed external shading such as overhanging eaves are appropriate. Sized correctly this can reduce excessive heat gain in summer while allowing solar heat gain in winter. As a rule of thumb, eave depth should be 25% of the height from the window sill to the bottom of the eave.
Reference: Sustainability Victoria - Energy Smart Housing Manual
Note: this rule of thumb aligns with the latest Sustainability Victoria guidance for cooler climates. Refer to page 40 of the Energy Smart Housing Manual (opens new window) for more discussion on why the rule of thumb eave was reduced from 45-50% to 25%, but also why hotter climates like Mildura may need eaves deeper than 25%. A preliminary energy rating will help you optimise eave / fixed shading depths for your climate).
For east and west facing glazing, adjustable shading is most appropriate, to deal with low sun angles in the morning and afternoon. Adjustable shading options include external blinds or louvres, conventional or roller shutters, sliding screens, angled metal or timber slats and adjustable / removable shading over pergolas.