Clean Is Green!

What do clean windows have to do with going green?

Establishing industry performance standards for glass has required a great deal of time, effort and money. These standards cover elements from solar energy reflectance (g-value) and light transmittance (t-value) to heat gain or loss (U-value). All of these elements can affect glass performance and the energy efficiency of a building.

Glass is often taken for granted as being basically a low or no-maintenance architectural feature. However, glass is like any other building surface and needs regular attention in order to maintain top performance levels. In most climates, but especially in places where it’s particularly hot and humid, loss of performance can easily occur. Condensation on exterior glazing is exposed to windblown dust and particulates, and in some cases, materials from a nearby construction site. Regular exposure like this can cause chemical reactions that lead to corrosion and physical damage of glass surfaces. During the more humid months, exterior condensation often occurs on buildings where high performance glass is used, such as energy efficient insulating glass (IG) with a low emissivity (low-E) coating. The condensation attracts airborne particulates creating a fine acidic coating that is left to bake in the hot sun. As this cycle repeats itself the surface of the glass can be damaged and performance levels drop below industry standards.

Regular cleaning of exterior glass surfaces is an important part of maintaining the overall quality of a building’s performance standards and energy efficiency, not just the appearance. Vast expanses of glass in some buildings can easily take up over half of the overall building surface. Take into consideration that those great expanses may not be delivering at peak efficiency, and a situation exists that can have a substantial, negative impact on energy use over the long term.

Another benefit to a regular schedule of cleaning is that it gives professional window cleaning crews the opportunity to inspect window seals up close. Aging and declining seals around vast expanses of glass can have an even greater impact on the loss of valuable heating and cooling dollars as they, literally, go out the window. Identifying deterioration early and taking steps to remedy it can ultimately reduce energy costs over the long term.

In an era when energy use is being heavily scrutinized by building owners, facility operators and tenants alike, it’s important to look at every element that can influence the overall energy efficiency of a building. High performance building glass, like any other building feature, will only stay in top condition with the proper attention to maintenance. Remember, clean is green!