Gas Fills

As higher-performance commercial facades are developed, the use of low-conductance gas fills becomes more common. Gas fills improve the thermal performance of insulating glazing units by reducing the conductance of the air space between the layers. Originally, the space was filled with air or flushed with dry nitrogen just prior to sealing. In a sealed-glass insulating unit, air currents between the two panes of glazing carry heat to the top of the unit along the inner pane and settle down the outer pane into cold pools at the bottom. Filling the space with a less conductive, more viscous, or slow-moving gas minimizes the convection currents within the space, reducing conduction through the gas and the overall heat transfer between the interior and exterior.

Manufacturers generally use argon or krypton gas fills, with measurable improvement in thermal performance. Both gases are inert, nontoxic, nonreactive, clear, and odorless. Krypton has better thermal performance than argon and is more expensive to produce. The optimal spacing for an argon-filled unit is the same as for air, about ½ inch. Krypton is particularly useful when the space between glazings must be thinner than normally desired, for example, ¼ inch. A mixture of krypton and argon gases is also used as a compromise between thermal performance and cost.

Argon and krypton occur naturally in the atmosphere, but maintaining long-term thermal performance is certainly an issue. Studies have shown less than 0.5% leakage per year in a well-designed and well-fabricated unit, or a 10% loss in total gas over a twenty-year period. The effect of a 10% gas loss would only be a few percent change in U-factor on an overall product basis. Keeping the gas within the glazing unit depends largely upon the quality of the design, materials, and, most important, assembly of the glazing unit seals.

Air Space

U-factor as a function of air-space thickness and emittance.

The use of low-conductance gas fills is far less common in commercial glazing than it is in residential windows. This results from the fact that solar control technologies are more important in typical commercial buildings than techniques for reducing heat transfer by conduction. However, as higher performance facades are developed, gas fills may become more common in commercial building windows as well.


Earless case design is very eye-catching, in general, high quality  uk Replica watches, look bright, popular style popular. JohnIsaac give this crazy sea water with the leather strap and folding buckle, while also providing another rubber strap as a backup Handbags Replica, and the appearance of the table is also very match. JohnIsaacRoughSea price is 1990 Replica Lv handbags francs and can be purchased through the website.Romain Jerome Space Invaders?Hermes Handbags In order to express their late 1970s video game ��Space Invaders�� tribute, Romaine Jerome introduced two limited edition UK Replica Handbags . Where a is color, another monochrome, each limited edition?Rolex replica watches?78.?Currently, users simply tap ever in the face of the?Replica Dior Handbags ?, or swipe card to access the application menu, the new update adds?mulberry Replica?��Home�� rights, individual interaction You can then replace the water feature.All through a series of taps �CReplica Rolex which (such as weather, notice or information and travel information), switch to a different state of information, using different face options, training data or open screen space, new activities will include bike-sharing.Finally, while also LG G?Hermes Replica Handbags?R, equipment, seemingly, it is excluded from the Andr oid after the previous update, the last of the Wi-Fi feature is enabled, updated benefits.

Facade Design Tool



Window Technologies

Case Studies

Tools & Resources