Large windows and exterior doors are popular in today’s Australian homes, bringing natural light inside and making the most of the outdoor living space.
While glass allows for natural light, fresh air, and sunshine to enter a home, it can also make maintaining a comfortable temperature and conserving energy a challenge.
The key is selecting glazing for new windows and doors that controls thermal performance, lowers energy costs, and lessens the building’s carbon footprint in the long run.
To the surprise of some specifiers, the type of glass used in windows and doors can have a major impact on maintaining a pleasant interior climate. A home’s windows can be the source of up to 87% of its incoming heat energy and the source of up to 40% of its outgoing heat energy.
The annual cost of heating and cooling can be cut in half or more by installing energy-efficient windows and doors. Energy-efficient glazing, for instance, can reduce the size of an air-conditioning system by as much as 30 percent, resulting in substantial savings.
Energy requirements for new homes and how to choose the right type of glazing to maximize energy efficiency are discussed in a video posted to YouTube by the Australian Glass and Window Association (AGWA).
NEW HOME ENERGY REQUIREMENTS
Construction of new dwellings must adhere to minimum energy efficiency standards. The Solar Heat Gain Coefficient (SHGC) and the U-value are two measures of energy performance.
A window’s SHGC is a number between zero and one that indicates how much heat is lost through it. For a window to have a SHGC of zero, no heat would be able to escape through it, while a SHGC of one would allow all of the heat to pass through. At a SHGC of 0.7, for instance, 70% of the sun’s heat would be transmitted through the glass.
Heat and cold can transfer through a window in three ways: conduction, radiation, and convection, all of which contribute to the U-value. A window with a low U-value will help save money on utility bills and keep the interior at a more comfortable temperature.
LOW-E VERSUS DOUBLE-PANE GLASS
Energy-efficient glass options typically include double glazing and Low E glass.
An item’s “E,” as in “Low E” glass, refers to its “emissivity,” or the amount of radiant energy emitted or absorbed by a surface. Designed to deflect long-wave infrared energy or heat, its metal coating is microscopically thin and transparent. Cost-effectively increasing a building’s energy efficiency by slowing the rate at which heat enters or exits.
The emissivity of an untreated glass window is around.84, while that of a Low E window or a window treated with Low E glass is only.02. As a bonus, it lowers the window or door’s SHGC and increases its U-value without any additional maintenance on your part.
By fusing together two panes of glass and connecting them with a metal or plastic “spacer bar,” we achieve double glazing. After being sealed, argon gas is pumped into the unit, and it’s finally ready to be installed into a window sash. The heat-conducting properties of windows are diminished by double glazing.
By sandwiching a layer of insulating argon gas between two panes of glass, double-paned windows can provide up to three times better thermal insulation than single-paned windows.
If you live in an area where summers are scorching hot and winters are bitterly cold, this is a fantastic option to consider.
Low E glass can be used in some double glazed window and door configurations.
WHAT CAN BE DONE TO BOOST THE BUILDING’S OVERALL EFFICACY
When the orientation of a building is taken into account during the design phase, it becomes more energy efficient. It is possible to maximise comfort and reduce heating and cooling costs by strategically placing windows in relation to the sun’s path throughout the year, depending on which direction the house faces.
The trick is to make the most of north-facing windows, which let in plenty of warmth in the winter but can be shaded to keep the heat out in the summer. The layout should place the structure so that it faces the sun.
It’s equally crucial to ensure a professional job when installing new windows. Poor installation can reduce the thermal efficiency of even the best windows.
EXPLAINING WHY WOOD INSULATION IS BETTER THAN OTHER OPTIONS
Wood is a natural thermal insulator due to the air pockets within its cellular structure, making it a vast improvement on aluminium in terms of energy performance when it comes to frame materials.
As a result of this natural insulation, less energy is needed inside the finished building, which lowers both initial costs and long-term energy needs. It can even be used as a component of a fix for reaching the levels of thermal comfort inside a building without the use of mechanical ventilation as specified by the Passive House standard.
And compared to other building materials, timber windowsrequire significantly less fossil fuel to manufacture.
HOW TO DECIDE ON A GLASS
When it comes to thermal comfort and a building’s overall energy footprint, windows and doors are among the most important architectural elements.
