Design Guide for Energy Efficiency
Step through the design stages in the table below, to check off some of the key considerations for selecting the right windows to create an energy efficient home.
| Design Stage |
Elements |
Considerations |
| Define the Base Building Design |
- Size, orientation & aspect
- Functionality & aesthetics of design
|
- Shading from neighbouring structures/natural features
- Climate & environmental factors
- How the building will be used
|
| Define Window Purpose & Layout |
- Size, number, which elevations, positioning
- Style of windows – aesthetics, openable area, maintenance & function
|
- Amount & evenness of natural light
- Views, privacy & overlooking
- Avoid glare & adverse reflected light
- Prevailing breezes to optimise natural ventilation
|
| Control Solar Heat Gain |
- Hot Climate – Low SHGC
- Cold – High SHGC
- Mixed – Medium SHGC
- Also elevation-specific solar control (e.g. western facing windows, high glare aspects, skylights, etc.)
|
- Physical shading
- Visible light transmission trade-off
- Aesthetics (inc. reflectivity of windows)
- Glare control
- Protection against thermal fracture
|
| Insulate |
- Basically always desirable
- Address inexpensive areas first (ceiling, walls, & floors)
- Then fix windows – insulating glass (double glazing & Low E) & non-conductive framing
|
- Practical limits of bulk insulation
- Ease of retrofit in existing dwellings
- Secondary benefits of different glazing configurations (noise control, reduced condensation, etc.)
|
Other Factors
(generally second order effect) |
- Air Infiltration – seals & build quality
- Ventilation – natural & forced
- Reflective surface treatments
- Thermal mass
- Roof cavity ventilation
- Internal partitioning
|
- Window type can impact air infiltration & ventilation
- Hours of occupancy can impact the relative benefits of ventilation & thermal mass
|
