Uncovered windows are responsible for up to 40% of heat loss from a home in winter, and up to 50% of unwanted heat gain in summer. A well-insulated home is warmer in the winter and up to 7 degrees cooler in the summer and can save as much hundreds per year in your energy costs. A well insulated home is warmer in the winter and up to 7 degrees cooler in the summer and can save as much as $300 per year in your energy costs.
| Various Glass Treatments | Heat Loss# |
| Unprotected single Glazing | 100% |
| Vertical or venetian blind | 100% |
| Heavy, lined drapes, no pelmet | 87% |
| Unlined drapes or Holland Blinds, pelmet | 78% |
| Double Glazing | 76% |
| Heavy, lined drapes, pelmet | 63% |
| Double grazing with low-ecoasting | 57% |
| Double glazing heavy drapes, pelmet | 47% |
*Some double glazing units may be substantial better that this
#Provided by Sustainable Energy Authority Victoria
Window coverings trap a layer of still air between the glass surface and the covering, reducing heat flow through the glass. So choosing the right window coverings to insulate your windows will save you energy and money on your power bills.
Saving money on your power bills is not the only benefit. Reducing power consumption will also help the environment by reducing CO2 emissions which contribute to global warming. In fact, local and state governments are now recommending the installation of curtains in new homes in order to acquire the
Curtains
Curtains can preserve up to 20% of the total heat in your home. They create a trapped layer of air between the fabric and the window, creating an insulating air pocket. Curtains can reduce heat gains by 33%. Curtains also stay cooler in the summer than other window treatments because their pleats and folds lose heat through convection. Curtain Linings you create a second layer of trapped air, and further insulation.
Pelmets
A Pelmet adds a barrier at the top of curtains to prevent air flow. Pelmets stop the warm air which has risen to the top of the room from going over the top of the curtain and transferring through the window.
Holland/ Roller Blinds
Holland Blinds are available in UV filtering and energy reflective fabrics which help control the amount of energy that enters and exits the room and vice versa.
Roman Blinds
The fabric layers in Roman Blinds create an air barrier which offers increased insulation. While the fabric can be the same as Curtains, the air layer is not as complex as that from a lined ‘S’-fold curtain.
Venetians Blinds
The numerous openings between the slats in Venetians offer flexibility in the summer months. Adjusting the slats allows you to control light, ventilation and they can be adjusted to block and reflect direct sunlight onto a light coloured ceiling. A light coloured ceiling will diffuse the light without much heat or glare.
Cellular Blinds/Honey Combs
The unique construction of Honey Combs Blinds allows air to be trapped within the cells creating a layer of insulation and a very energy efficient window covering. There are a number of factors affecting the thermal insulating characteristics cellular shades. There are two primary groups, light-filtering and light-blocking. These thermal resistance values can then be altered by the size of the cell, number of cells, plus the under lying material structure (reflective value). Various manufactures quote rather excessive R values, without any substantial evidence as to how those figures were calculated
Plantation Shutters
Window shutters, both interior and exterior, are very effective at reducing heat gain and loss in your home.
Internal Plantation Shutters
Internal Shutters are best combined with Curtains for improved insulation. Like Blinds, Shutters work best for summer shading. Movable or fixed louvers allow ventilation and natural daylight to enter a room whilst blocking out some of the radiation.
Plantation Outdoor/External Shutters
External Aluminum and Roller Shutters offer weather protection, added security and the advantage of not having to use up interior space. They are an effective way to reduce heat gain through windows in summer and keep a home cool, some statistics showing external shading can reduce heat gains by 70-85%.
Awnings
Window Awnings can greatly improve your home’s energy efficiency in summer. Awnings can reduce solar heat gain in the summer by up to 77% on windows. The role of an Awning is to regulate the amount of solar energy that reaches the facade of your home, especially the parts of it that are glass. An external shade will block out up to 80% of the direct heat load on a window, resulting in an immediate reduction in heat transfer. Adjustable or retractable Awnings can be rolled up in the winter to let the sun warm your house.
ZIPscreen
With the addition of Zipscreen to your external out door entertainment area you can maximize the use of these area during the winter months and provide UV protection during the summer. eZIP products can be very energy efficient, minimize your carbon footprint.