This is part of a continuing series on simple, inexpensive energy saving tips to do now that will produce real energy cost savings and greenhouse gas (GHG) emission reductions, suggestions that will not put out your staff, and will make you look like a hero.
Windows represent one of the easiest modes of outside air infiltration into a building, causing a building to burn more fuel to heat or to use the AC to cool more than normal. However, window replacement is not a cheap energy saving strategy. Studies have shown that the cost of procuring and installing state-of-the-art windows (double pane, with a solid frame and overall high resistance) is high given the direct potential energy savings. But windows are important. Little affects worker productivity more than working next to single pane windows with a noticeable “draft,” or workers being excessively cold or warm.
There are window strategies you can implement to reduce your energy costs. Work with your maintenance staff to begin regular window inspections and a caulking program. Make sure the windows are completely shut on hot or cold days and that there is no infiltration of outside air, each defeating the efforts of your AC and boiler systems.
Replacing windows can be problematic given the hesitancy of a tenant to upgrade a building it does not own or an owner to invest in something that may have little impact on building value. It is a great expense relative to energy cost savings. But if you are an owner needing to upgrade windows, there are ways to prioritize to save money. It may make sense to initially replace only those windows near where the most people work. Or perhaps replace only those windows that are north facing. One (glass) office building that I performed an energy audit for had both – nearly all of their office workers worked in perimeter offices in one row next to north-facing single-pane windows. The economics of replacing those windows only with double-pane, high R windows was reasonable. Another energy saving potential opportunity in parts of your building where no or few people work is to remove windows altogether and fill in with insulated wall material.
Finally, if you are responsible for buying replacement windows for your company, be careful to buy the right ones that will perform properly to save you heating and AC costs. The FTC recently warned 14 window manufacturers about making false energy-saving claims, such as not backing up savings claims with scientific data and using misleading (“apples to oranges”) case studies. Here are two articles summarizing the issues: http://www.ftc.gov/opa/2012/08/windows.shtm and http://business.ftc.gov/blog/2012/08/make-your-claims-crystal-clear. Do your research to get the best replacement windows for your company’s benefit.
Marc Karell is the owner of Climate Change & Environmental Services. CCES has experience in performing site-specific energy audits and recommending proven strategies and technologies to reduce your facility’s energy usage (fuel and electricity), saving you money with a good ROI and without inconveniencing your staff. See our website: www.CCESworld.com for more information or e-mail me at karell@CCESworld.com.