Anatomy of an energy-efficient window: Quality Frame Materials: A variety of durable, low-maintenance framing materials reduce heat transfer and help insulate better. Multiple Panes: Two panes of glass, with an air or gas-filled space in the middle, insulate much better than a single pane of glass.
The most environmentally friendly windows are those that are double glazed – meaning they feature two panes of glass with a void in between filled with insulating gas. The addition of UPVC (Unplasticised Polyvinyl Chloride) composite frames also assists the windows' thermal properties.
Insulated Glass
Triple pane windows are considered some of the best and most sustainable windows on the market. The thermal performance of insulated glass is almost entirely unmatched.
Eco-Friendly Materials
Aluminium windows are probably the material of choice as they are durable, efficient and sustainable. As aluminium is a recyclable material, homeowners needn't worry about the environmental impact. Timber windows are also a good choice, by using a natural material.
Energy-Efficient Glass
With dual-pane or triple-pane glass, inert argon gas can be used between panes of glass to improve insulating properties. Laminated, tempered, tinted and obscure insulating glass can also add ultraviolet protection to help keep your home more comfortable and energy efficient.
Yes. Emergency management agencies specifically recommend using “aluminum foil-covered cardboard” between windows and drapes to reflect heat back outside.
Many window design professionals agree that new, quality windows should last between 15 and 20 years before you start to think about replacing them. Most companies producing vinyl windows often provide a 20-25 year warranty, which is essentially a lifetime warranty – the expected lifetime of the product.
Homeowners who invest in higher efficiency windows generally save around 12% on their electric bill every year. Therefore, a home that usually spends $200 a month to heat their home would save $24 every month. Depending on the climate where you live and the windows you've replaced, your savings could be even better.
Double paned windows are much more energy efficient than single paned windows. Experts suggest that in warm climates, like Jacksonville, FL, that double paned windows can reduce energy usage by up to 18 percent.
Sealing around windows and doors is one of the most common uses for expanding foam. But the high-expansion stuff can actually push the jamb inward, making them impossible to open. Avoid this by using minimal expanding foam.
Bubble wrap works by increasing the isolative value of the window, making it effective in keeping the heat out in summer and preventing heat loss in winter. "The still layer of air trapped in the bubbles gives a cheap double-glazed-type effect," Ms Edwards said.
A solar control glass is a glass with a special coating designed to reduce the amount of heat entering a building. It reflects and absorbs heat as well as filtering light for reduced glare. Using a solar control glass can reduce the need for air-conditioning and blinds.
They insulate not just via the glass, but also by filling the spaces in between with a noble gas such as argon or krypton. They are both colorless, odorless, non-toxic gasses with a lower thermal conductivity than air. That means more energy saved, less cold inside your home and lower heat bills.
As a natural resource, wood is renewable, light and strong, and has low thermal transmittance. Using wood as a material makes window and door frames more energy efficient. The BRE Green Guide recognises timber as a sustainable material, rating timber frames A or A+ for sustainability.
The composition of a package is another way to measure its sustainability, and glass is made from three abundant and natural ingredients: sand, limestone and soda ash. When glass breaks down, it remains safe and stable, and releases no harmful chemicals into the soil.
Low impact, high performance
Thanks to advances in recycling and product innovation, PVC-U is now widely recognised as a sustainable option for the construction industry. Old PVC-U window frames can be recycled and repurposed up to 10 times without the quality or performance deteriorating.
An Eco-house (or Eco-home) is an environmentally low-impact home designed and built using materials and technology that reduces its carbon footprint and lowers its energy needs.
Wood: Wood windows offer the best insulative value, though they also require more upkeep than vinyl, wood-clad or aluminum frames.