Energy efficient windows can improve a home or building’s efficiency and sustainability. They may also help keep heat out during Queensland summers, retain winter warmth and regulate indoor temperatures throughout the year.
The right choice depends on the building, its existing windows and the result you want to achieve. This guide explains what to consider before upgrading windows in a home or community titles scheme.
What are energy efficient windows?
Energy efficient windows are selected to help manage heat entering and leaving a building. They can support more consistent indoor temperatures and reduce the need for heating or cooling.
This can be useful in homes and buildings with large areas of glass, particularly where windows receive strong direct sun. Window performance also depends on the glazing, frames, seals, fittings, orientation and shading.
A window that performs well in one building may not be the best option for another. Consider the window’s location and the condition of the surrounding structure.
For more practical ways to manage household energy use, see our guides on how your body corporate can save on energy and how to reduce your summer power bill.
How do energy efficient windows work?
Windows affect how much outdoor heat enters a building and how much indoor warmth escapes. Choosing suitable windows can help the building respond to seasonal conditions.
In Queensland, this may mean reducing unwanted summer heat from direct sunlight. In cooler months, suitable windows may help retain warmth inside the home. The result depends on the window design, its position and other parts of the building.
Windows should be considered alongside external shading, curtains, blinds, ventilation and the building’s orientation, which can all affect indoor temperatures. Poorly positioned windows may increase summer heat or make it harder to retain warmth during winter.
Energy efficient windows do not guarantee lower energy costs. Before making a decision, consider the building as a whole and the conditions affecting each window.
Which window features improve energy performance?
Discuss the following features with a qualified glazing or building professional:
- Glazing: Different glass products may perform differently in direct sun and shaded locations.
- Frames: The frame forms part of the window system and should be considered alongside the glass.
- Seals and fittings: Gaps, draughts or failed seals can undermine an otherwise suitable glazing upgrade.
- Shading: A window may need external or internal shading to manage direct sunlight.
- Orientation: North-, south-, east- and west-facing windows can experience different conditions, so the same specification may not suit every elevation.
- Tint and coatings: These may affect how much heat and daylight enter a room. Very dark tinting can also reduce daylight and may mean artificial lighting is needed during the day.
The appearance of the window is only one part of the decision. Ask how the complete window system is expected to perform in the location where it will be installed.
Check whether the proposed product is suitable for the existing opening. Changing the glass may not address problems with frames, seals or surrounding building elements.
Should you retrofit existing windows or replace them?
Retrofitting existing windows and specifying windows for a new building involve different considerations.
A retrofit may involve changing part of the existing window system, adding a treatment or replacing the complete window. The condition of the current frames, seals and fittings will affect which options are practical. If the existing frame allows draughts or water to enter, changing the glass alone may not resolve the underlying problem.
A complete replacement may provide more opportunity to select the frame, glazing and shading together. It may also involve more disruption, different costs and work to areas that could be common property.
For either approach, obtain a clear scope of work. It should explain what will be removed, what will be installed, how the work will affect surrounding areas and who will maintain the completed work.
The body corporate and lot owners have different maintenance responsibilities. First, identify the scheme’s registered survey plan and regulation module. Then use the boundaries between the lot and common property to work out who is responsible.
What should a body corporate consider before changing windows?
The body corporate should first establish whether the proposed work is maintenance or an improvement. The Queensland Government explains that an improvement can include a structural or non-structural change, while maintenance and improvement are treated differently. A change, such as swapping an existing item for another, may need to be considered as part of this assessment.
Window replacement may affect common property, the appearance of the building or more than one lot. The body corporate should review the survey plan, the community management statement and any relevant by-laws before arranging the work.
If the work is an improvement to common property, approval is required. For schemes under the Standard, Accommodation and Small Schemes modules, the approval required for a body corporate improvement depends on the cost. A committee resolution may apply up to the basic improvements limit, an ordinary resolution may apply within the ordinary resolution improvement range, and a special resolution is required for work costing more than $2,000 multiplied by the number of lots.
Those limits apply to the total cost of a project where several improvements form one project. The body corporate or committee should not split related window work into separate amounts to avoid considering the full project cost.
If a lot owner wants to make a change, they should consider whether it affects common property and whether any by-laws affect the proposed work. An owner improvement to common property requires committee or body corporate approval. The committee can approve an owner improvement where the total cost is less than $3,000, it does not detract from the appearance of the lot and the body corporate is satisfied it is unlikely to breach the owner’s duties as an occupier.
The owner must comply with approval conditions and maintain the improvement. They must also give the body corporate details of the type and value of the work.
How can you compare window options?
Start by describing the problem you want to address. Is the room overheating in the afternoon, losing warmth during winter or affected by draughts around the frame?
Then compare options based on:
- the window’s orientation and exposure to direct sun
- the existing frame and seal condition
- the proposed glazing, tint or coating
- the amount of daylight the room needs
- shading and ventilation already available
- installation requirements and disruption
- responsibility for future maintenance
- the effect on the building’s external appearance.
Ask suppliers to explain the expected performance of the complete installation rather than focusing only on one product feature. Request product information, a written scope, warranty details and confirmation of any work required to common property.
A body corporate should also consider whether different parts of the building need different solutions. A product suitable for a shaded bedroom may not be suitable for a western-facing living area.
When should you get professional advice?
Get advice before choosing a product or committing to work, particularly where the building has older frames, signs of water entry, failed seals or unusual window openings.
A qualified glazing or building professional can assess the existing windows, orientation, shading and installation requirements. They can also explain whether a proposed retrofit is suitable or whether a broader replacement is needed.
For a body corporate, confirm the maintenance responsibility and approval position before obtaining quotes or arranging installation. If the work affects common property, the body corporate should follow the approval requirements that apply to the scheme and project.
Energy efficient windows can support more comfortable and efficient buildings, but the best result depends on the complete window system and the decisions made before installation. If your body corporate is considering window work, contact our team at reception@stratacare.com.au.
