Windows that insulate like Walls

Paarhammer windows are already known for their excellent insulation performance but a new glass technology brings this performance to a completely new level. Heat Mirror Glass is relatively unknown in the Australian market, but has been used for years overseas. For example, New York’s Empire State Building was refurbished in 2010, including the use of Heat Mirror glazing throughout – changes which were projected to save US$4.4M per year and 105,000 tonnes CO2 emission in 15 years.

Heat Mirror (HM) insulating glass units (IGU) contain one or more clear, low-emissivity films suspended within the sealed airspace of a dual-pane IGU to create super insulating cavities that buffer against heat loss or heat gain. By combining with high-performance low-emissivity glass and argon or krypton gas fill, Heat Mirror IGUs can be used to tune building envelope performance by either maximizing or minimizing solar heat gain while optimizing daylighting and views. Through their extraordinarily high insulation properties and Solar Heat Gain Coefficient (SHGC)performance matched to the needs of the site and local climate, Heat Mirror IGUs allow significant reductions in energy costs, and maintain a far more uniform air within the building for a more comfortable internal environment year round.

Other benefits are 99% block-out of harmful UV rays and 33% weight reduction compared to the equivalent triple glazed unit. Also, a comprehensive Life Cycle Analysis completed by Eastman (Heat Mirror Manufacturer) shows that replacing the third pane of glass with film enables Heat Mirror IGUs to consume 30% less energy Cradle-to-Grave than the equivalent unit using conventional triple glazing. Heat Mirror IGUs have been recognized by Popular Science Magazine as one of the “Top 100 Inventions of the Millennium”.

Paarhammer sources its Heat Mirror units through Australia’s leading glass manufacturer Viridian Glass, part of Australian Building Products Company, CSR. Lachlan Austin, Viridian’s General Manager, Marketing adds: “Beyond the obvious insulation benefits, Heat Mirror IGUs bring a number of additional advantages over conventional double glazing.Acoustically, these units can offer approximately 4db noise reduction over an equivalent unit without the suspended film.In terms of daylight access, the high selectivity offered by the coatings on the film provides a high ratio of Light to Radiant Heat– e.g. Visible Light Transmission (VT)=0.7 with a Solar Heat Gain Coefficient (SHGC) of 0.53- in essence it lets the light in like clear, but cuts the heat like grey. The SHGC can be stepped down further by the use of different films, glass and coatings in the make-up. It’s a remarkably flexible product”.

A comparison of U-values of Paarhammer Openable Tilt and Turn Windows*, depending on glass configuration:

With double glazed IGU 1.8-2.2

With triple glazed IGU1.3-1.8

With Heat Mirrors in double glazed IGU 1.0-1.25

With such performance, windows made with Heat Mirror technology can substantially lower your energy bills, or permit you far greater expanses of windows and doors without diminishing your building’s energy performance.

*Fixed units by Paarhammer have already an exceptionally low WERS rating from 0.8 U-value